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Stock librarian Brandon King looks at some items that have recently been in the media that you can borrow from Suffolk Libraries.
Civilisations: how do we look? / the eye of faith, by Mary Beard
The companion book to the two programmes Mary Beard is presenting in the BBC’s new series Civilisations. David Olusoga’s companion book is one of our non-fiction top tips for April above.
Red Sparrow, by Jason Matthews
Jennifer Lawrence’s latest film is based on this 2013 book by Jason Matthews.
“A Russian agent targets a CIA operative to uncover a mole at the heart of the Russian intelligence service. Dominika Egorova, former prima ballerina, is sucked into the heart of Putin’s Russia, the country she loved and spat out as the twists and turns of betrayal unravel.”
No Place to Lay One’s Head, by Françoise Frenkel, translated by Stephanie Smee
This recent Radio 4 Book of the Week is the moving wartime memoir of Françoise Frenkel, a Jewish woman originally from Poland who ran La Maison du Livre, a French bookshop in Berlin, from 1921 to 1939.
Girl in Snow, by Danya Kukafka
This debut novel from Danya Kukafka was a recent Radio 2 Book Club choice.
“Who are you when no one is watching? When beloved high school student Lucinda Hayes is found murdered, no one inher sleepy Colorado suburb is untouched - not the boy who loved her too much; not the girl who wanted her perfect life; not the police officer assigned to investigate.
“In the aftermath of the tragedy, these three unforgettable characters - Cameron, Jade, and Russ - must each confront their darkest secrets in an effort to find solace, the truth, or both.”
Bookworm: a memoir of childhood reading, by Lucy Mangan
The book behind Joaquin Phoenix’s latest film, which has been nominated for the Palme d’Or.
“A former Marine and ex-FBI agent, Joe has seen one too many crime scenes and known too much trauma, and not just in his professional life. Solitary and haunted, he prefers to be invisible. He doesn’t allow himself friends or lovers and makes a living rescuing young girls from the deadly clutches of the sex trade.
“But when a high-ranking New York politician hires him to extricate his teenage daughter from a Manhattan brothel, Joe uncovers a web of corruption that even he may be able to unravel. When the men on his trial take the only person left in the world who matters to him, he forsakes his pledge to do no harm. If anyone can kill his way to the truth, it’s Joe.”
You Were Never Really Here, by Jonathan Ames
The book behind Joaquin Phoenix’s latest film, which has been nominated for the Palme d’Or.
“A former Marine and ex-FBI agent, Joe has seen one too many crime scenes and known too much trauma, and not just in his professional life. Solitary and haunted, he prefers to be invisible. He doesn’t allow himself friends or lovers and makes a living rescuing young girls from the deadly clutches of the sex trade.
“But when a high-ranking New York politician hires him to extricate his teenage daughter from a Manhattan brothel, Joe uncovers a web of corruption that even he may not be able to unravel. When the men on his trail take the only person left in the world who matters to him, he forsakes his pledge to do no harm. If anyone can kill his way to the truth, it’s Joe.”


In very short
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- User accounts contain user names, email addresses, submissions, and submission dates.
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- I need the email as identifier, resetting passwords, and for letting users know of mistakes in the dataset or benchmarks.
Contact information
{{project_name}} at {{project_url}}
Contact: Karsten Behrendt
Email: dataset_terms at kbehrendt com


Unlimited Games. How should Red play 32?
pips Red=149 White=144
(CorrectAnswer= 0/0, ErrorScore= 0)
You can’t blitz White’s rear checker, but you can prime it. 13/11, 13/10 threatens to prime it while 8/5, 7/5 makes the golden point and slots the bar-point. A much more direct approach.
White’s sixes are duplicated all over the board and so making the 5-pt is the stand-out play and 13/11, 13/10 is an error. If you move the blot on White’s 10-pt to his 9-pt the two plays become much closer.
Note that any split of the rear checkers is a blunder because it is the wrong game plan.
White’s sixes are duplicated all over the board and so making the 5-pt is the stand-out play and 13/11, 13/10 is an error. If you move the blot on White’s 10-pt to his 9-pt the two plays become much closer.
Note that any split of the rear checkers is a blunder because it is the wrong game plan.
1. Cubeful 2-ply 8/5 7/5 Eq.: -0.114 0.473 0.156 0.005 - 0.527 0.157 0.012 2. Cubeful 2-ply 13/11 13/10 Eq.: -0.150 (-0.036) 0.458 0.134 0.004 - 0.542 0.151 0.008 3. Cubeful 2-ply 24/21 11/9 Eq.: -0.194 (-0.080) 0.462 0.134 0.006 - 0.538 0.191 0.009 4. Cubeful 2-ply 24/22 11/8 Eq.: -0.196 (-0.082) 0.451 0.122 0.004 - 0.549 0.166 0.005 5. Cubeful 2-ply 24/21 8/6 Eq.: -0.206 (-0.092) 0.456 0.133 0.005 - 0.544 0.183 0.009


Victoria Falls, Zimbabwe is home to the world’s largest waterfall. Considered one of the 7 Wonders of the Natural World, this magnificent site is the centerpiece of this amazing adventure. Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.
Trip Details
- 6 days and 6 nights in 4 star accommodations including hot breakfast daily -
- Sunset Cruise on the Zambezi River where you’ll see hippos, crocodiles, elephants and more -
- Elephant Back Safari -
- Night Safari on a “Big 5” reserve -
- Soaring helicopter ride over the falls -
- Victoria Falls Bridge Tour with magnificent views of the gorge -
- High Tea at Victoria Falls Hotel overlooking the Victoria Falls Bridge -
- Safari through Zambezi National Park -
- Z River ligambeziht raft trip -
- BOMA Dinner- An unforgettable cultural experience -


File: gitter.coffee
| Defined in: | src |
Method Summary
Method Details
~
(void)
use(robot)
| Defined in: | src |
~
(void)
use(robot)
Quickly fuzzy find classes, mixins, methods, file:
Control the navigation frame:
You can focus and blur the search input:


Bootstrap Categorical
Amiri, S., & Modarres, R. (2017). Comparison of tests of contingency tables. Journal of biopharmaceutical statistics, 1-13. Doi: 10.1080/10543406.2016.1269786.
The bootstrap tests given in Amiri and Modarres (2017) is implemented in R and explained here. The source of codes are stored in Github.
##### Necessary libraries in R
> library(RCurl)
> library(MASS)
> library(boot)
### Read codes from github
> script <- getURL("https://raw.githubusercontent.com/saeidamiri1/saeidamiri1.github.io/master/codes/bootcat/bootcat.R", ssl.verifypeer = FALSE)
> eval(parse(text = script))
########
###########################################
###### Example used in paper
## enter data in a matrix
> m<-matrix(c(7,2,5,10,0,1),nrow=2)
> chisq.test(m)$p.value
[1] 0.06676657
Warning message:
In chisq.test(m) : Chi-squared approximation may be incorrect
> fisher.test(m)
Fisher's Exact Test for Count Data
data: m
p-value = 0.06219
alternative hypothesis: two.sided
################
##Bootsrap test
> B<-2000
> I<-dim(m)[1]
> J<-dim(m)[2]
> BX(m,B)
[1] 0.044
There were 50 or more warnings (use warnings() to see the first 50)
> BP(m,B)
[1] 0.032
There were 50 or more warnings (use warnings() to see the first 50)
###########################################
###########################################
###########################################
> chisq.test(m)$p.value
[1] 0.815404
> fisher.test(m)
Fisher's Exact Test for Count Data
data: m
p-value = 0.8175
alternative hypothesis: two.sided
> BX(m,B)
[1] 0.8335
There were 50 or more warnings (use warnings() to see the first 50)
> BP(m,B)
[1] 0.8285
There were 50 or more warnings (use warnings() to see the first 50)


{include file='part-head.htm'}>
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java.lang.Object es.ucm.look.locationProvider.DeviceSensor
public class DeviceSensor
Process sensors information and decides whether the device is moving or not.
| Field Summary | |
|---|---|
static float[] |
devA
|
static float[] |
devM
|
static float[] |
devO
|
static boolean |
flagMoving
|
static float[] |
geomagnetic
|
static float[] |
gravity
|
static java.lang.Object |
lockMoving
|
static java.lang.Object |
lockSensing
|
static float[] |
mI
|
static float[] |
mR
|
static float[] |
refA
|
static float[] |
refO
|
static float |
wsAggregate
|
static int |
wsPosition
|
static float[] |
wsSequence
|
| Constructor Summary | |
|---|---|
DeviceSensor()
|
| Method Summary | |
|---|---|
static void |
disableMoving()
|
static void |
enableMoving()
|
static float |
getHeading()
Return the angle between the device direction and the north direction in the Earth's coordination system |
static float[] |
getRefAcceleration()
Synchronized get function to get the reference acceleration in the Earth's coordination system |
static boolean |
isMoving()
|
static void |
setDevA(float[] raw)
Set the accelerometer sample values and calibrate the data if required * @param raw The raw output from accelerometer |
static void |
setDevM(float[] raw)
Set the magnetic sample values and calibrate the data if required |
static void |
setDevO(float[] raw)
|
static boolean |
toEarthCS()
Convert the sensor data from the device's coordination system to the world's coordination system including motion and orientation |
| Methods inherited from class java.lang.Object |
|---|
equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
| Field Detail |
|---|
public static float[] devA
public static float[] devM
public static float[] devO
public static boolean flagMoving
public static float[] geomagnetic
public static float[] gravity
public static java.lang.Object lockMoving
public static java.lang.Object lockSensing
public static float[] mI
public static float[] mR
public static float[] refA
public static float[] refO
public static float wsAggregate
public static int wsPosition
public static float[] wsSequence
| Constructor Detail |
|---|
public DeviceSensor()
| Method Detail |
|---|
public static void disableMoving()
public static void enableMoving()
public static float getHeading()
public static float[] getRefAcceleration()
public static boolean isMoving()
public static void setDevA(float[] raw)
public static void setDevM(float[] raw)
raw
- The raw magnetic output from sensorpublic static void setDevO(float[] raw)
public static boolean toEarthCS()
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Blazor Training Videos – DevExpress Blazor Training Course Free Training Course on Blazor covers all fundamental Blazor concepts, such as Component Structure, Dependency Injection, JavaScript Interop, and more.
Amazon.com: USB C Charger [GaN Tech], Anker 30W Ultra Compact Type-C Wall Charger with Power Delivery, PowerPort Atom PD 1 for iPhone 11/11 Pro/Max/XS/XR, iPad Pro, MacBook 12'', Pixel, Galaxy, and More: AnkerDirect Buy USB C Charger [GaN Tech], Anker 30W Ultra Compact Type-C Wall Charger with Power Delivery, PowerPort Atom PD 1 for iPhone 11/11 Pro/Max/XS/XR, iPad Pro, MacBook 12'', Pixel, Galaxy, and More: Wall Chargers - Amazon.com ✓ FREE DELIVERY possible on elig...
Announcing pricing decrease for Azure App Service on the Premium plan | Azure updates | Microsoft Azure We are happy to announce a price reduction of an average of 35% for Linux App Service on the Premium v2 plan (pricing may vary by regional meters). This price reduction makes the decision point between hosting on a Standard App Service plan or a Premium v...
Simon Peyton Jones how GHC type inference engine actually works Keynote at ZuriHac 2019 Simon is one of the designers of the Haskell language, an inspiring leader for the whole Haskell community, and the main developer of GHC, the de facto standard Haskell compiler. He also chairs the Computing At School group, which...
natemcmaster/LetsEncrypt ASP.NET Core integration for free HTTPS certificates from https://letsencrypt.org - natemcmaster/LetsEncrypt
Vintage Shaking Ghost - Sonic Control - Sound Activated Toy ,"args":{"cr":"US","show_miniplayer_button":"1","fflags":"show_thumbnail_on_standard=true&html5_remove_pause=false&html5_stop_video_in_cancel_playback=true&desktop_image_companion_wta_support=true&html5_request_size_padding_secs=3.0&html5_player_min_build...
How to build a plugin system on the web and also sleep well at night The solution we found helps us run Figma plugins in a safe way — i.e. not eval(UNTRUSTED_CODE).
Why Are So Many Developers Hating on Object-Oriented Programming? - The New Stack Does Object Oriented Programming really make it easier for programmers to develop? Of is an alternatve like functional programming a better way to go?
Node Material: Light Node In this video, David shares some updates on the upcoming Node Material Editor! Learn how to add light nodes into your custom shaders! Play along with the video here: https://playground.babylonjs.com/#4I3SIR#1 Also please remember that this is an evolvi...


by a Peckish Student
Posted on 26/04/2016 at 14:24
Sometimes a bowl of cereal just won’t cut it. Nothing beats a Full English breakfast, and there are a multitude of cafes and restaurants in Liverpool that make an excellent fry-up.
We usually spend our days wandering the winding streets of Liverpool but today we decided we would enter the realms of the bustling business district. As we sat down on a bench soaking up the hectic atmosphere full of modern professionals on their way to their mid-day rendezvous, we decided we needed to move away from the rather serious and corporate atmosphere. Although we had heard some riveting reviews from fellow friends about Moose Coffee, it was the antlers hanging from the roof that turned our window shopping into a sit down meal. Located on 6 Dale Street, Moose is a favourite amongst some of the most important people in the city who use Moose as a way to revitalise themselves whilst having some fun in the process. We eventually went for the infamoose (couldn’t resist) Moose Breakfast as, for many, this is the best way to start the day. It was a concoction of garlic and mustard potatoes, perfectly fried eggs, bacon and thick toast. We then decided to go for another beloved breakfast amongst the Moose regulars which was the New York Moose, New York on a plate but much more than a big apple. Crisp and delicate Parma ham lay on top of runny in the middle poached eggs that rested on soft muffins – this alone would have been enough, but the whole meal was then saturated in a sticky and succulent hollandaise sauce that was a compliment to every flavour present. It is coming to places like Moose coffee that really instills in us that passion for why we started this venture. There is so much homogeneity in the world and although the bright lights of Starbucks and your name on the cup as well as the red cup synonymous with Costa may be enticing, the true beauty of exploring one’s city is surely to find the places that are unique to your own? To the average punter, Moose may just be a great breakfast haunt with a Moose’s head on top of Benjamin Franklins’ body, but to us this is a statement that there are still a daring few willing to take risks in and enjoy their success so much more when they pay off. Like them on Facebook ‘Moose Coffee’ and follow them on Twitter @MooseCoffee but make sure you head down soon.
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java.lang.Object pl.mbdev.mysql.SqlQuery pl.mbdev.mysql.SqlConnectedQuery
public class SqlConnectedQuery
Copyright 2011 Mateusz Bysiek<EMAIL_ADDRESS>http://mbdev.pl/ Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.
| Constructor Summary | |
|---|---|
SqlConnectedQuery(SqlConnection connection)
|
|
SqlConnectedQuery(SqlConnection connection,
pl.mbdev.mysql.SqlQuery.QueryType type,
java.lang.String statement)
|
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SqlConnectedQuery(SqlConnection connection,
java.lang.String statement)
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| Method Summary | |
|---|---|
boolean |
createTable(java.lang.String statement)
CREATE TABLE [IF NOT EXISTS] 'Table' ('column1' INT, 'column2' VARCHAR(50)) |
boolean |
deleteFrom(java.lang.String statement)
DELETE FROM 'Table' WHERE column = 'value' |
boolean |
dropTable(java.lang.String statement)
DROP [TEMPORARY] TABLE [IF EXISTS] 'table1', 'table2' |
java.lang.Object |
execute()
|
boolean |
insertInto(java.lang.String statement)
INSERT INTO 'Table' (column1, column2) VALUES (row1val1, row1val2),(row2val1, row2val2) |
java.sql.ResultSet |
select(java.lang.String statement)
SELECT * FROM 'Table' WHERE column = 'value' |
boolean |
update(java.lang.String statement)
UPDATE 'Table' SET column1 = value, column2 = value WHERE column = 'value' |
| Methods inherited from class pl.mbdev.mysql.SqlQuery |
|---|
createTable, deleteFrom, dropTable, executeOn, insertInto, select, setQueryType, update |
| Methods inherited from class java.lang.Object |
|---|
equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
| Constructor Detail |
|---|
public SqlConnectedQuery(SqlConnection connection)
connection
- public SqlConnectedQuery(SqlConnection connection, java.lang.String statement)
connection
- statement
- public SqlConnectedQuery(SqlConnection connection, pl.mbdev.mysql.SqlQuery.QueryType type, java.lang.String statement)
connection
- type
- statement
- | Method Detail |
|---|
public java.lang.Object execute()
public java.sql.ResultSet select(java.lang.String statement)
statement
-
public boolean insertInto(java.lang.String statement)
statement
-
public boolean createTable(java.lang.String statement)
statement
-
public boolean deleteFrom(java.lang.String statement)
statement
-
public boolean update(java.lang.String statement)
statement
-
public boolean dropTable(java.lang.String statement)
statement
-
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Q: What are the different types of delay at a node in a packet-switch network?
A: A node in a packet-switch network may suffer from processing, queuing, transmission, and propogation delays together make up what is called total nodal delay.
Q: What is meant by the phrase "A Network of Networks"?
A: This is part of our theme of layers of abstraction. There are routers and communication links which span the entire globe, and this in itself is a network. However, there is not one single ISP which manages this entire global network. Instead, ISPs charge and segment networks on an individual basis, or sometimes in small chunks of routers. These are each networks as well, and we therefore call this system a network of interconnected networks.
Q: In our context, what is a protocol?
A: A protocol defines the format and the order of messages exchanged between two or more communicating entities, as well as the actions taken on the transmission and/or receipt of a message or other event.
Q: Please name the two network application architectures and give one advantage of each.
A: The two architectures are client-server and peer to peer or P2P. Client-server models have many advantages, the primary one being a simple structure which allows end users to access the entire network by connecting solely to the central server, providing ease of access as well as relative security. Peer to peer has the advantage of a direct connection to other users, so that the network connections are not dependent on a single point of failure.
Q: For what kind of application is it critical to have low delay, and for what kind is it not ciritical for low delays, but desirable for high throughput?
A: Internet telephony, video calling, and gaming requires low delay because the real-time information is critical. For file transfering it is not critical to have low delays, but it is desirable to have high throughput to get the entire file quickly.
Q: What is the relationship between a socket and a port? What are the well known port numbers?
A: In the context of this course a socket is an application level software component that allows
the application to transmit and receive data, and a port is an endpoint on a network which is defined
at an operating system level. A socket on an application is designated a port number, allowing the
computer to porperly deliver data from the network to the correct process on the local machine.
P26 from Chapter 2. Page 177 Suppose Bob joins a BitTorrent torrent, but he does not
want to upload any data to any other peers (so called free-riding).
a. Bob claims that he can receive a complete copy of the file
that is shared by the swarm. Is Bob’s claim possible? Why or why not?
b. Bob further claims that he can further make his “free-riding” more efficient
by using a collection of multiple computers (with distinct IP
addresses) in the computer lab in his department. How can he do that?
Answer to part A: Bob's claim is possible. There is nothing inherent in the peer-to-peer architecture to prevent someone from "free-riding". For a time BitTorrent's primary weakness was its reliance on a base of altruistic users. Because of the legal gray area that file sharing services represent, some users are reluctant to expose themselves by sharing parts of files themselves and instead stick strictly to downloading. As recently as five years ago, BitTorrent has been implementing reward systems for users who have a good record of contributing to the community, punishing those who take advantage of the services it has to offer.
Answer to part B: Bob could make his file harvesting more efficient by using multiple computers. Consider the answer to part A which demonstrates that BitTorrent uses a reward system to prevent users from downloading files without contributing themselves. There is nothing to stop Bob from sharing the same piece of a file from multiple different computers, wile using those distinct computers to download distinct portions of a file. This would allow Bob to gain more file fragments per shared fragment, proportional to the number of computers Bob was able to use.
P26 from Chapter 3. Page 293Consider transferring an enormous file of L bytes from Host A to Host B.
Assume an MSS of 536 bytes.
a. What is the maximum value of L such that TCP sequence numbers are not
exhausted? Recall that the TCP sequence number field has 4 bytes.
b. For the L you obtain in (a), find how long it takes to transmit the file.
Assume that a total of 66 bytes of transport, network, and data-link header
are added to each segment before the resulting packet is sent out over a
155 Mbps link. Ignore flow control and congestion control so A can pump
out the segments back to back and continuously.
Answer to Part A: If the Maximum Segment Size is 536 bytes, and the TCP sequence flag requires 4 bytes, then the maximum amount of data in each TCP segment is 536 - 4 = 532 bytes. Since the sequence number is alloted 4 bytes, there can be 2 ^ 32 or 4,294,967,295 distinct segments in the file. This means that the maximum size of L is (2 ^ 32) x 532 bytes = 2.284 terabytes.
Answer to Part B: On a 155 Mbps network, ignoring flow and congestion control, this download should take 2,464.1 hours. Around 100 days.
The lab instructions simply ask us to answer the questions.
Q: What is the IP address and TCP port number used by your client computer to transfer the file to gaia.cs.umass.edu? What is the IP address and port number used by gaia.cs.umass.edu to receive the file?
A: The source computer's IP address is <IP_ADDRESS> and the TCP port number is 4444. The destination computer's IP address is <IP_ADDRESS> and it uses port 80.
Q: What is the sequence number of the TCP SYN segment that is used to initiate the TCP connection between the client computer and gaia.cs.umass.edu? What is it in the segment that identifies the segment as a SYN segment?
A: The sequence number of the TCP SYN segment is the value used to intitiate the TCP handshake between the two computers. The value is 0. The SYN flag has a value of 1 which is what denotes that this is a SYN segment.
Q: What is the sequence number of the SYNACK segment sent by gaia.cs.umass.edu to the client computer in reply to the SYN? What is the value of the ACKnowledgement field in the SYNACK segment? How did gaia.cs.umass.edu determine that value? What is it in the segment that identifies the segment as a SYNACK segment?
A: The sequence number in reply to the SYN is 0. The ACK value in the SYNACK segment is 1. The gaia.cs.umass.edu computer adds 1 to the initial field in the SYNACK segment from the client computer to achieve the SYNACK segment flags.
Q: What is the sequence number of the TCP segment containing the HTTP POST command? Note that in order to find the POST command, you'll need to dig into the packet content field at the bottom of the Wireshark window, looking for a segment with a "POST" within its DATA field.
A: The sequence number of the segment containing the HTTP POST command is 1.
Q: Consider the TCP segment containing the HTTP POST as the first
segment in the TCP connection. What are the sequence numbers of the first six
segments in the TCP connection (including the segment containing the HTTP
POST)? At what time was each segment sent? When was the ACK for each
segment received? Given the difference between when each TCP segment was
sent, and when its acknowledgement was received, what is the RTT value for each
of the six segments? What is the EstimatedRTT value (see page 237 in text)
after the receipt of each ACK? Assume that the value of the EstimatedRTT is
equal to the measured RTT for the first segment, and then is computed using the
EstimatedRTT equation on page 249 for all subsequent segments.
Note: Wireshark has a nice feature that allows you to plot the RTT for
each of the TCP segments sent. Select a TCP segment in the “listing of
captured packets” window that is being sent from the client to the
gaia.cs.umass.edu server. Then select: Statistics->TCP Stream Graph-
>Round Trip Time Graph.
A: The HTTP POST segment is the first segment. The sequence numbers for segments 1-6 are 1, 566, 2026, 3486, 4946, and 6406, respectively. The sending and receiving times can be listed as follows:
| Segment Number | Sent Time | ACK received time | RTT |
| Segment 1 | 0.0274 | 0.0538 | 0.0254 |
| Segment 2 | 0.0453 | 0.0765 | 0.0346 |
| Segment 3 | 0.0497 | 0.1352 | 0.0691 |
| Segment 4 | 0.0502 | 0.1715 | 0.1164 |
| Segment 5 | 0.0762 | 0.2159 | 0.1421 |
| Segment 6 | 0.0774 | 0.2714 | 0.1852 |
Q: What is the length of each of the first six TCP segments?
A: THe first segment is 565 bytes, this is the HTTP POST. The next five are all 1460 bytes, these are MSS.


public abstract class Session
extends java.lang.Object
implements java.lang.Runnable
As an MVC framework, every piece of game logic can be split into the following components: - Model for storing data - View for using processed data - Controller for processing data
To communicate between controllers and views, Session uses events and messages.
Events are sent by controllers, and can be captured by both controllers and views. An event can be sent to any number
of event handlers, and from any controller. Events are implemented as distinct immutable classes that implement the
Event
interface. Each thread gets its own event queue that it can process at its own leisure.
Messages are registered by controllers, and can be used by views and other controllers. Unlike events, only one message handler can exist. (ie. only one controller can implement 'addPlayer'.) Messages are used as a way for views to communicate with controllers.
It is important to note that Session's controllers are designed to be self-sufficient.  For this to work,
we give each thread their own SessionContext
object, with, among other things, an event queue.
| Constructor and Description |
|---|
Session() |
| Modifier and Type | Method and Description |
|---|---|
void |
addEvent(Event event)
Add an event to the event queue
|
void |
addModel(java.lang.Object model) |
void |
cancelTask(TimerTask task)
Cancel a running task created with
setTask(long, Runnable) |
SessionContext |
getContext()
Get the SessionContext used by the Session object
|
java.lang.Thread |
getThread() |
abstract void |
init() |
void |
run()
Main Session loop
|
TimerTask |
setTask(long ms,
java.lang.Runnable runnable)
Add a task to be executed after some time
|
static SessionContext |
start(java.lang.Class<? extends Session> klass,
java.lang.Object... args)
JavaFX-style start method.
|
abstract void |
update() |
public static SessionContext start(java.lang.Class<? extends Session> klass, java.lang.Object... args)
klass
- public void run()
run
in interface java.lang.Runnable
public TimerTask setTask(long ms, java.lang.Runnable runnable)
ms
- time in milliseconds to waitrunnable
- method to executepublic void cancelTask(TimerTask task)
setTask(long, Runnable)
task
- taskpublic abstract void init()
public abstract void update()
public void addModel(java.lang.Object model)
public void addEvent(Event event)
event
- event to be addedpublic SessionContext getContext()
public java.lang.Thread getThread()


CCModding
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CCModding
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Discord
If you are interested in joining the CrossCode Modding Discord server, click the button below!


{% if g.user.is_authenticated and g.user.can_visit: %}
{{ _("Please use the buttons below to log the action taken on your visit of this drop point.") }}
{{ _("Please log in as a bottle collector using the login form at the top of this page in order to visit drop points.") }}
{% endif %} {# vim: set expandtab ts=4 sw=4: #}


I was, FINALLY, able to almost correctly calibrate de Kinect. After noticing that the error was mostly in the X direction and that the RGB image and the point cloud where not completely overlapping I considered that the error could be in the RGB and Depth intrinsic calibration of the camera. The process of the intrinsic calibration was redone, the depth_registration parameter to launch the drivers of the Kinect was set to False and the the other launch files were changed so the drivers of the Kinect were the last thing to be launched.
This are the results of the first calibration after applying this alterations.
| The X direction | The Y direction |
| The X direction | The Y direction |
More calibrations will be done to reach the most suitable transformation.


PRIMARY LIABILITY
Primary liability coverage pays for damage or injuries to others caused by an accident for which the covered driver is responsible. A minimum of $750,000 coverage is normally required for most vehicles over 10,000 pounds gross vehicle weight. However, we recommend protecting yourself and your drivers with at least $1,000,000 or more, which is more in line with industry standards.


Tool: Permutation Generator
Object 01
1
Object 02
2
Object 03
6
Object 04
24
Object 05
120
Object 06
720
Object 07
5040
Object 08
40320
Object 09
362880
Object 10
3628800
Prefix sets with:
Suffix sets with:
Delimit objects with:
Join sets with:
Direct save. Output wrap is
on
off.
Output Box - Permutations will display here. Enter up to 10 objects to permute into the object input fields above. Objects can be any text from a single letter to whole sentence. Permuted sets can have a prefix and/or suffix added via the prefix/suffix fields. Join objects within each set via the delimit field. Join sets via join field. Entering \x into any field will produce a line break. WARNING: 10 objects will produce 3628800 permutations! Many browsers will display a stop script messages and results will be slow to load. When generating large amounts of permutations check "Direct save." to directly save results as a output file. This will prevent browser lock-up from trying to load large amounts of results into this browser field. Privacy of Data: This tool is built-with and functions-in Client Side JavaScripting, so only your computer will see or process your data input/output.
Unix
Dos.


Planifier is a calendar and task organizer for students. It includes all the functions for students to make reminders and track deadlines while looking at their calendar.
The website was a separate project. Link to concept design here
Planifier is a calendar and task organizer for students. It includes all the functions for students to make reminders and track deadlines while looking at their calendar.
Planifier Video Promo from Cedric Le Mercier on Vimeo.


Thanks for playing along with my little about me game. Now that you know a little bit about me, let me fill you in on my professional background. I am a self-directed, hard-working drone pilot & technician, health physics technician, Jr. developer, and former small business owner with over four years of UAS R&D and maintenance experience, and over 1,400 hours of logged flight time across the U.S.
- Work Experience
- Montico Inc. - Chief Pilot & Maintenance Officer (05/16-Present)
- Recruited and trained 14 new-hire pilots in all aspects of flight safety, federal regulation, processes, procedures, and checklists.
- Directed a team of 3 developers in the writing and testing of workplace software for the management of commercial UAS fleets and their respective telemetry data/logs.
- Consulted & advised for many clients directly including AT&T, AT&T Bell Labs, Swiss Re, & Tech Mahindra.
- Redesigned and enhanced UAS platforms to surpass competitors capabilities and exceed client’s expectations.
- RSRS - Jr. Radiation Control Technician (09/14-05/16)
- Designed, assembled, & deployed an unmanned robotic system for the storm line pipe inspections and radiological surveying.
- Responsible for site wide data entry, quality control measures for radiological instruments, field surveying and sampling, laboratory management and testing.
- Health Physicist responsible for completing routine radiological surveys in Magnuson Park, Seattle Wa.
- Samuels Jewelers - Shift Lead (08/12-08/14)
- Developed new software practices to overhaul day-to-day operations and optimize employee productivity.
- Trained and mentored 6 employees in daily operations and strategic sales.
- CheerForce Central Valley - Owner/Operator & Head Coach (05/12-08/14)
- Directed and managed a 6,000 sq. ft. gym, with 7 employees, 130+ athletes, and $220,000 annual revenue.
- Shaped a team of 32 athletes who excelled, qualifying for and competing at USASF Cheerleading Worlds-Summit 2014, Orlando FL.


N-Credible Mazes
问题描述 :
An n-tersection is defined as a location in n-dimensional space, n being a positive integer, having all non-negative integer coordinates. For example, the location (1,2,3) represents an n-tersection in three dimensional space. Two n-tersections are said to be adjacent if they have the same number of dimensions and their coordinates differ by exactly 1 in a single dimension only. For example, (1,2,3) is adjacent to (0,2,3) and (2,2,3) and (1,2,4), but not to (2,3,3) or (3,2,3) or (1,2). An n-teresting space is defined as a collection of paths between adjacent n-tersections.
Finally, an n-credible maze is defined as an n-teresting space combined with two specific n-tersections in that space, one of which is identified as the starting n-tersection and the other as the ending n-tersection.
输入:
The input file will consist of the descriptions of one or more n-credible mazes. The first line of the description will specify n, the dimension of the n-teresting space. (For this problem, n will not exceed 10, and all coordinate values will be less than 10.) The next line will contain 2n non-negative integers, the first n of which describe the starting n-tersection, least dimension first, and the next n of which describe the ending n-tersection. Next will be a nonnegative number of lines containing 2n non-negative integers each, identifying paths between adjacent n-tersections in the n-teresting space. The list is terminated by a line containing only the value ?. Several such maze descriptions may be present in the file. The end of the input is signalled by space dimension of zero. No further data will follow this terminating zero.
输出:
For each maze output it’s position in the input; e.g. the first maze is "Maze #1", the second is "Maze #2", etc. If it is possible to travel through the n-credible maze’s n-teresting space from the starting n-tersection to the ending n-tersection, also output "can be travelled" on the same line. If such travel is not possible, output "cannot be travelled" instead.
样例输入:
2 0 0 2 2 0 0 0 1 0 1 0 2 0 2 1 2 1 2 2 2 -1 3 1 1 1 1 2 3 1 1 2 1 1 3 1 1 3 1 2 3 1 1 1 1 1 0 1 1 0 1 0 0 1 0 0 0 0 0 -1 0
样例输出:
Maze #1 can be travelled Maze #2 cannot be travelled
题目链接：http://acm.hdu.edu.cn/showproblem.php?pid=1307
先说一下题意，就是给你n维起始点和终点的坐标，然后后面给出一系列的点，每一行表示这两个点之间有通路，最后让你判断一下能否从起点出发走到终点。
由于最多不超过10维，那么我们把每个点的坐标转化为一个整数，然后建邻接表，这样dfs就可以了（值得注意的是我们用set来判重，当然你也可以用数组什么的）
可以说是dfs+map+set的妙用了！
#include<iostream> #include<cstdio> #include<cmath> #include<vector> #include<set> #include<map> using namespace std; int st,ed; map<int,vector<int> >Map; set<int>Set; int n; bool Input(int &num,int n){ num=0; int x; for(int i=1;i<=n;i++){ scanf("%d",&x); if(x==-1)return false; num=num*10+x; } return true; } bool dfs(int st,int ed){ if(st==ed)return true; for(int i=0;i<Map[st].size();i++){ int v=Map[st][i]; //只能返回0或1，1表示该数已经插入 if(!Set.count(v)){ Set.insert(v); if(dfs(v,ed))return true; } } return false; } int main(){ int x,t=1; while(scanf("%d",&n),n){ Map.clear(),Set.clear(); Input(st,n); Input(ed,n); int s,e; while(Input(s,n)){ Input(e,n); Map[s].push_back(e); Map[e].push_back(s); } if(dfs(st,ed)){ printf("Maze #%d can be travelled\n",t++); }else printf("Maze #%d cannot be travelled\n",t++); } return 0; }
(adsbygoogle = window.adsbygoogle || []).push({});
有没有C++编译的？
不好意思，写错了．应该是 path[0]=0, visited[V] = true;
不错的网站，建议添加些比赛信息
很好的思路，可以借鉴
很好的思路，可以借鉴
很好的思路，可以借鉴
很好，找的就是这一题
输入样例作为一个整体输入，带回车
Gucci New Fall Arrivals
This is really nice to know. I hope it will be successful in the future. Good job on this and keep up the good work.
还是有些难度的！


You have gotten off the waitlist for the event {{ event_name }}! Click here to view the event.
Have a nice day!


Holy shit, FIRSTNAME
It was great to see you yesterday! I think this is the first time anyone has ever brought a trained bear to an onboarding event! People will be talking about this for a loooong time. You must tell me more about your hobby some day.  At least no one will ever forget their onboarding!
I hope you will keep showing up for the social events, but don't feel obligated to do something big every time. The important thing is that we get to know each other!
You really shouldn't bring it to the next event, though. Remember what you learned at the Ethics course, during the onboarding: Immanuel Kant taught us that it is important to obey authority, so that your actions will follow a consistent general rule. He even demonstrated that it would be wrong to lie to the police, if they want to know where your friend is hiding. Please try to keep that in mind.
Now that we got that out of the way, you should definitely come to the team club night tonight! We all go to a club together and have fun! It's a great way to get to know your colleagues in a more informal environment :).
Traditionally, everyone signs up to buy a round of some kind of drink for the rest of the team. I look forward to seeing what you come up with :). Remember, you can't drink a bear, so you will have to think of something else to contribute.
Benedetto Tornincasa
Human Relations
Senior Consultant / Haka Leader


My name is Peter Chang, and I am a Graphic Designer, specializing in futuristic vector art. I’m a big fan of cyberpunk art, music, and video games.  My goal is to implement my inspirations artistically, from my perspective, and my understanding of science and math. I am attracted to many different forms of art and you will often find me photographing artistic pieces of interest to learn from and keep my art fresh.
I obtained my Graphic Design B.A. at CSU East Bay in Hayward, CA, and will be attending the Interaction Design Master’s program in the fall. I have experience working with the entire Adobe Suite, specializing in Adobe Illustrator and Indesign. I use a lot of HTML, CSS, and JavaScript for coding websites. Currently a Personal Assistant and Graphic Designer to Fiona Ma, California State Treasurer, and I also work as a Student Assistant in the CSUEB Astronomy Lab. With these skills I will create various inventions and manufacture a tangible cyberspace for the entire world to experience.


Demonstration of using cooperatively scheduled background tasks using the requestIdleCallback() method.
requestIdleCallback()


I can't change the direction of the wind, but I can adjust my sails to always reach my destination. by Jimmy Dean
Hello and welcome to my page . My name is Laud and I am a tech enthusiast, software developer, and a blogger.


Main article: Game of Thrones: Season 1)
| No. overall | No. in season | Title | Directed by | Written by | Original air date | U.S. viewers (millions) |
|---|---|---|---|---|---|---|
| 1 | 1 | "Winter Is Coming" | Tim Van Patten | David Benioff & D. B. Weiss | April 17, 2011 | 2.22 21 |
| 2 | 2 | "The Kingsroad" | Tim Van Patten | David Benioff & D. B. Weiss | April 24, 2011 | 2.20 22 |
| 3 | 3 | "Lord Snow" | Brian Kirk | David Benioff & D. B. Weiss | May 1, 2011 | 2.44 23 |
| 4 | 4 | "Cripples, Bastards, and Broken Things" | Brian Kirk | Bryan Cogman | May 8, 2011 | 2.45 24 |
| 5 | 5 | "The Wolf and the Lion" | Brian Kirk | David Benioff & D. B. Weiss | May 15, 2011 | 2.58 25 |
| 6 | 6 | "A Golden Crown" | Daniel Minahan | Story by : David Benioff & D. B. Weiss Teleplay by : Jane Espenson and David Benioff & D. B. Weiss | May 22, 2011 | 2.44 26 |
| 7 | 7 | "You Win or You Die" | Daniel Minahan | David Benioff & D. B. Weiss | May 29, 2011 | 2.40 27 |
| 8 | 8 | "The Pointy End" | Daniel Minahan | George R. R. Martin | June 5, 2011 | 2.72 28 |
| 9 | 9 | "Baelor" | Alan Taylor | David Benioff & D. B. Weiss | June 12, 2011 | 2.66 29 |
| 10 | 10 | "Fire and Blood" | Alan Taylor | David Benioff & D. B. Weiss | June 19, 2011 | 3.04 30 |


Every coach has their own specific names for positions. Use the boxes below to name the field positions the way you want.


"The Wreck of the Edmund Fitzgerald" is a song written, composed, and performed
by Canadian singer-songwriter Gordon Lightfoot to commemorate the sinking of the bulk carrier SS
Edmund Fitzgerald on Lake Superior on November 10, 1975.
Lightfoot drew his inspiration from
Newsweek's article on the event, "The Cruelest Month", which it published in its November 24, 1975,
issue. Lightfoot considers this song to be his finest work.
Appearing originally on Lightfoot's 1976 album Summertime Dream, the single version hit number 1 in
his native Canada (in the RPM national singles survey) on November 20, 1976, barely a year after
the disaster. In the United States, it reached number 1 in Cashbox and number 2 for two weeks in
the Billboard Hot 100 (behind Rod Stewart's "Tonight's The Night"), making it Lightfoot's
second-most-successful single behind "Sundown".
Overseas it was at best a minor hit, peaking at
number 40 in the UK Singles Chart.
The song is written in Dorian mode.
The legend lives on from the Chippewa on down
Of the big lake they called 'gitche gumee'
The lake, it is said, never gives up her dead
When the skies of November turn gloomy
With a load of iron ore twenty-six thousand tons more
Than the Edmund Fitzgerald weighed empty
That good ship and crew was a bone to be chewed
When the gales of November came early
The ship was the pride of the American side
Coming back from some mill in Wisconsin
As the big freighters go, it was bigger than most
With a crew and good captain well seasoned
Concluding some terms with a couple of steel firms
When they left fully loaded for Cleveland
And later that night when the ship's bell rang
Could it be the north wind they'd been feelin'?
The wind in the wires made a tattle-tale sound
And a wave broke over the railing
And every man knew, as the captain did too,
T'was the witch of November come stealin'
The dawn came late and the breakfast had to wait
When the gales of November came slashin'
When afternoon came it was freezin' rain
In the face of a hurricane west wind
When suppertime came, the old cook came on deck sayin'
Fellas, it's too rough to feed ya
At seven pm a main hatchway caved in, he said
Fellas, it's been good t'know ya
The captain wired in he had water comin' in
And the good ship and crew was in peril
And later that night when his lights went outta sight
Came the wreck of the Edmund Fitzgerald
Does any one know where the love of God goes
When the waves turn the minutes to hours?
The searches all say they'd have made Whitefish Bay
If they'd put fifteen more miles behind her
They might have split up or they might have capsized
They may have broke deep and took water
And all that remains is the faces and the names
Of the wives and the sons and the daughters
Lake Huron rolls, superior sings
In the rooms of her ice-water mansion
Old Michigan steams like a young man's dreams
The islands and bays are for sportsmen
And farther below Lake Ontario
Takes in what Lake Erie can send her
And the iron boats go as the mariners all know
With the gales of November remembered
In a musty old hall in Detroit they prayed,
In the maritime sailors' cathedral
The church bell chimed till it rang twenty-nine times
For each man on the Edmund Fitzgerald
The legend lives on from the Chippewa on down
Of the big lake they call 'gitche gumee'
Superior, they said, never gives up her dead
When the gales of November come early
From : {{article.username}}
Comment : {{article.comment}}


Backface Culling
Assignment Goals:
- Learn how to calculate face normals using the cross product
- Learn how backface culling is used to decide what faces to draw
- Learn about the limitations of backface culling
Instructions for you to follow in this document will be highlighted in blue.
Don't forget to cite your sources!
Filling in the Faces
Complete the following:
- Start with your code for drawing in a perspective projection (or your code from the dot/cross product assignment if that includes your perspective drawing code).
- Create an array called
face_colors = ["red","green","blue","cyan","magenta","yellow"];
. You can replace the color strings with any color names or formats from the CSS color specification.
- In
draw_cube_persp
, in your for loop over each face, add the following code after you have finished creating the path for the face:
ctx.fillStyle = face_colors[i];
ctx.fill();
- Run your code and rotate the cube around. It should look almost correct: each face will be drawn in with a color, but some faces will be drawn on top of other faces when they're actually behind them. There are three fixes for this:
- Painter's Algorithm: Sorting the faces from furthest to closest to the camera, and draw them in that order. For some types of geometry, it is easy to tell which triangles are closest/furthest from the camera. In other cases, two faces will intersect and one will need to be drawn partially on top of and partially underneath another and this won't work at all.
- Backface culling: Removing the faces not facing the camera. We do not want to draw faces that aren't facing the camera (backfaces) and so we cull (remove) them from the render process. This will solve our cube problem, but won't solve overlap problems.
- Z-buffers: Keeping track of how far each pixel is from the camera when we draw it. We will implement this process in a later activity.
Backface culling is incredibly fast because we already need to calculate the direction of each face for lighting and other effects, we can calculate angles quickly with linear algebra, and once we've decided to cull a face we don't need to do any more processing for that face. Most 3d graphics engines implement a combination of these techniques.
You can see backface culling in action when you fall through the map in video games. This shows up often in speedruns [warning: flickering] and you can see it for yourself in this THREE.js demo by flying beneath the terrain. The geometry between the camera and where the camera is supposed to be aren't drawn, because those walls are "facing" away from the camera, towards where the camera is expected to be.
Normal Vectors
In your draw_persp_code
function in your loop over each face, we need to check if the normal vector to the face is pointing towards or away from the camera. To do this, we need two vectors: one from the camera to the face which we will call vc
, and another which is normal to the face.
Complete the following:
- Locate your labeled drawing of your cube
- Create a new array
cubenorms
such that:
-
cubenorms[i] = [x,y,z]
is a three-element array representing a vector
- This vector has length 1, is perpendicular to the
i
th face, and is facing outward from the cube.
- In your loop over each face, calculate
vn
by:
- Applying your rotation matrices to the normal vectors of the face.
- Do not apply the translation to the normal vectors of the face. Translations only affect points, not directions!
-
vc
should be a vector from the camera (located at the origin) to the face. It can be the location of any vertex or the center of the face, after being transformed (rotated and translated), but before being projected.
Make sure vc
is the location of the vertex after being rotated and translated!
- Now, we need to calculate if these two vectors are pointing in the same direction. You can do this using dot products. THREE.js offers
v.dot(w)
which returns the dot product of the vectors v
and w
or you can calculate the dot product using your vec_dot
function.
- Use an
if
statement to only draw and fill a face if vc
and vn
are in opposite directions.
Some resources for learning about dot products can be found in the previous assignment.
Calculating Normal Vectors
Given two 3D vectors v and w, their cross product v × w is a vector:
- with length the area of the parallelogram formed by the two vectors
- perpendicular to those two vectors
- obeying a right-hand rule for those two vectors (if you point the fingers of your right hand in the direction of v and can rotate them to point in the direction of w, your thumb is pointing in the direction of v × w)
This is really useful for:
- Calculating the area of triangles (half the area of the parallelogram)
- Reasoning about the orientation of a triangle
- Distinguishing clockwise and counter-clockwise triangles
THREE.js has a built-in cross product function. To calculate the cross product of vectors v and w, use new THREE.Vector3().crossVectors(v,w)
. Or use your vec_cross
function from before.
Some resources for learning about cross products can be found in the previous assignment.
Complete the following:
- In your code for drawing the bunny, in your for loop over each face, assign three Vector3s to the vertices of the triangle after it's been transformed (rotated and translated, but before the projection). Call them t0, t1, and t2. Make sure they're in the right order.
- Calculate t1-t0 and t2-t0. These are the vectors representing two edges of the triangle. THREE.js has a built-in vector subtraction function. To calculate the difference of vectors v and w, use
new THREE.Vector3().subVectors(v,w)
.
- Calculate the cross product of these two vectors. Call it
vn
.
- As before, calculate the dot product of
vn
and vc
to determine if you should draw the face. vc
can be any point in the triangle, either one of the vertices or its center.
- You'll need to pick a color for each face, and it's better to pick a different color for each face. You can use
ctx.fillStyle = "hsla("+i+",100%,50%,1)";
, where i is the index of the face. You could also populate an appropriate length face_colors
array using Math.random()
.
- The result should look something like the below:
Note that most of the faces are drawn correctly, but a few faces are drawn on top of faces they should be behind. Why is that?
Above and Beyond
The following are optional suggestions for improving your interactive:
- You can create a neat transparency effect on the cube by first drawing the back faces, then drawing the front faces with a partially transparent color. This sort of effect is much trickier to pull off correctly for more complex geometry, since it requires keeping track of the order that triangles appear from furthest to closest to the camera for every pixel.
- When deciding what color to color each face, use the normal vector that you computed in some way. This can create an effect that is unrealistic but very good at communicating the shape of an object. You can see an example here and here.


| < Day Day Up > |
Hack 59 Intrusion Detection with Snort, ACID, MySQL, and FreeBSD
How the alert administrator catches the worm.  Not only is the administrator required to fix problems and keep things running smoothly, but in some cases he is also responsible for keeping the network from becoming worm food. This often entails monitoring the traffic going to and from the network, identifying infected nodes, and loading numerous vendor patches to fix associated vulnerabilities. To get a better handle on things, you can deploy an Intrusion Detection System (IDS) on the LAN to alert you to the existence of all the nastiness associated with the dark side of the computing world. This hack will show you how to implement a very effective and stable IDS using FreeBSD, MySQL, Snort, and the Analysis Console for Intrusion Databases (ACID). While that means installing and configuring a few applications, you'll end up with a feature-rich, searchable IDS capable of generating custom alerts and displaying information in many customizable formats. 6.7.1 Installing the SoftwareWe'll assume that you already have FreeBSD 4.8-RELEASE or newer installed with plenty of disk space. The system is also fully patched and the ports collection is up-to-date. It also helps to be familiar with FreeBSD and MySQL commands. <IP_ADDRESS> Install PHP4, Apache, and MySQLWe'll start by installing PHP4, Apache, and the MySQL client. As the superuser: # cd /usr/ports/www/mod_php4 # make install clean When the PHP configuration options screen appears, choose the GD Library Support option. Leave the other default selections, and choose OK. The build itself will take a while because it must install Apache and the MySQL client in addition to PHP. <IP_ADDRESS> Install MySQL-serverYou'll also need the MySQL server, which is a separate port. To ensure this port installs correctly, temporarily set the system hostname to localhost: # hostname localhost # cd /usr/ports/databases/mysql40-server # make install clean This one will also take a while. <IP_ADDRESS> More installationsThere are a few other ports to install. The next three applications are used by ACID to create graphs of the output. ACID supports bar graphs (as shown in Figure 6-3), line graphs (Figure 6-4), and pie charts (Figure 6-5). Figure 6-3. An ACID bar graphFigure 6-4. An ACID line graphFigure 6-5. An ACID pie chartWe'll need adodb , a database library for PHP: # cd /usr/ports/databases/adodb # make install clean PHPlot adds a graph library to PHP so it will support charts: # cd /usr/ports/graphics/phplot # make install clean JPGraph adds more support to PHP for graphs: # cd /usr/ports/graphics/jpgraph # make install clean Finally, we must install ACID and Snort. Start by modifying snort's Makefile to include MySQL support: # cd /usr/local/ports/security/snort # vi Makefile Change: CONFIGURE_ARGS= --with-mysql=no to: CONFIGURE_ARGS= --with-mysql=yes Save your changes and exit. Finally, install acid, which will also install snort using your modified Makefile: # cd /usr/ports/security/acid # make install clean 6.7.2 ConfiguringNow that we've installed all the necessary pieces for our IDS, it's time to configure them to work together. <IP_ADDRESS> Configure Apache and PHPYou'll need to make two changes to Apache's configuration file, /usr/local/etc/apache/httpd-conf. First, search for #ServerName, remove the hash mark (#), and change www.example.com to your actual server name. Then, for security reasons, change ServerSignature On to ServerSignature Off. This prevents the server from providing information such as HTTP server type and version. Most admins who run IDSs on their networks like to keep their presence somewhat hidden, since there are exploits/tools written to defeat IDS detection. <IP_ADDRESS> Configure PHPAfter installing PHP, you will notice two sample configuration files in /usr/local/etc, php.ini-dist and php.ini-recommended. As the name suggests, the latter is the recommended PHP 4-style configuration file. It contains settings that make PHP "more efficient, more secure, and [encourage] cleaner coding." Since our focus is security, I recommend using this file. Configuring PHP is as simple as copying the sample configuration file to /usr/local/etc/php.ini: # cd /usr/local/etc # cp php.ini-recommended php.ini <IP_ADDRESS> Configure MySQLMySQL supports several configurations. Use my-small.cnf or my-medium.cnf if you have less than 64 M of memory, my-large.cnf if you have 512 M, and my-huge.cnf if you have 1-2 G of memory. Later, if you find your system running out of swap space, you can stop mysql and copy one of the smaller *.cnf files to fix the problem. In my example, I'll copy over my-large.cnf: # cp /usr/local/share/mysql/my-large.cnf /etc/my.cnf Next, set up the initial databases and install the server: # /usr/local/bin/mysql_install_db # /usr/local/etc/rc.d/mysql-server.sh start You can use the sockstat command to confirm that the MySQL server is running. You should see MySQL listening on port 3306: # sockstat | grep mysql USER COMMAND PID FD PROTO LOCAL ADDRESS FOREIGN ADDRESS mysql mysqld 16262 5 tcp4 *:3306 *:* mysql mysqld 16262 6 stream /tmp/mysql.sock Then, set the password for the root MySQL user. You'll have to use the FLUSH PRIVILEGES command to tell MySQL to reload all of the user privileges, or the server will continue using the old (blank) password until it restarts: # /usr/local/bin/mysql -u root
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 1 to server version: 4.0.16-log
Type 'help;' or '\h' for help. Type '\c' to clear the buffer.
mysql>SET PASSWORD FOR root@localhost=PASSWORD('
your_password_here
');
mysql>FLUSH PRIVILEGES;
Query OK, 0 rows affected (0.00 sec) Then, you can create the snort database: mysql>CREATE DATABASE snort; Query OK, 1 row affected (0.00 sec) Now we can create a MySQL user with sufficient permissions to access the new snort database. Do not use the MySQL root user! By creating a new user who has access to only one database, we've limited the damage an attacker could do if he ever gained access to this account. MySQL uses the GRANT command to give users access to databases. You can control which types of statements the user can issue, as well as the network hosts from which the user can access MySQL. localhost is a nice, safe setting, as we only need to access the database from the local machine. Again, this restricts the damage that an attacker could do from another compromised host. mysql> GRANT INSERT,SELECT ON snort.* to snort_user_here @localhost \ IDENTIFIED BY ' snort_users_password '; Query OK, 0 rows affected (0.00 sec) mysql> GRANT INSERT,SELECT,CREATE,DELETE on snort.* \ to snort_user_here @localhost IDENTIFIED BY ' snort_users_password '; Query OK, 0 rows affected (0.01 sec) mysql> FLUSH PRIVILEGES; Query OK, 0 rows affected (0.01 sec) mysql> quit Bye <IP_ADDRESS> Configure SnortFirst you'll need to download the latest sources from http://www.snort.org (currently v2.0.5). After unpacking, use the create_mysql file to create the necessary tables in the snort database. That's all the configuration you need; you can now simply delete the unpacked directory. # tar xvfz snort-2.0.5.tar.gz # cd snort-2.0.5/contrib # cp create_mysql /tmp # /usr/local/bin/mysql -p < /tmp/create_mysql snort Enter password: Enter the MySQL root password here # cd /usr/local/etc # cp snort.conf-sample snort.conf # vi snort.conf Scroll down until you reach the # output database: log, mssql, dbname=snort user=snort password=test line. Insert the following lines beneath it: output database: log, mysql, user=mysql_user_name password=mysql_users_ password dbname=snort host=localhost output database: alert, mysql, user=mysql_user_name password=mysql_users_ password dbname=snort host=localhost Now page down toward the bottom of the file and select the types of rules you want to monitor for. Keep in mind that the more rules you use, the more work snort will have to do, using up CPU cycles and memory that might be better used elsewhere. For example, if you don't want to monitor X11 or Oracle on any computer on your network, comment out those rules. When you're done, save your changes and exit. Finish by creating the snort log directory: # cd /var/log # mkdir snort <IP_ADDRESS> Configure ACIDStart by tightening the permissions of the configuration file: # chmod 644 /usr/local/www/acid/acid_conf.php
Then, change the section that contains alert_dbname = "snort_log"; to include the appropriate entries: $alert_dbname = "snort"; $alert_host = "localhost"; $alert_port = ""; $alert_user = "mysql_snort_user"; $alert_password = "mysql_snort_users_password"; Leave the Archive parameters alone, unless you want to create a separate database for snort to store archived alert messages in. To do this, you'll need to log into MySQL, create an archive database, set the appropriate permissions, and run the mysql_create script again as described earlier. The Snort and ACID documentation describe this in more detail. You do need to tell ACID where to find some of the libraries installed earlier. In particular, change: $ChartLib_path = ""; to: $ChartLib_path = "/usr/local/share/jpgraph"; 6.7.3 Running ACID# /usr/local/sbin/apachectl start /usr/local/sbin/apachectl start: httpd started Then, link the ACID web directory. Of course, for security reasons, I recommend giving the link name something other than acid. # cd /usr/local/www/ # ln -s /usr/local/www/acid /usr/local/www/snort Point your web browser to http://localhost/snort/acid_main.php and click the Setup link. Click the Create ACID AG button to create the extended tables that ACID will use. When it finishes, you should see something similar to the following: Successfully created 'acid_ag' Successfully created 'acid_ag_alert' Successfully created 'acid_ip_cache' Successfully created 'acid_event' Now click the Main page link to be taken to ACID's main display page. At this point you might ask, "Where are the alerts?" There aren't anyŚwe didn't start snort! 6.7.4 Running SnortFirst, try starting snort manually to make sure it works. Use the -i switch to specify the network interface that will be monitoring traffic. In my case, it is xl0. # cd /usr/local/etc # /usr/local/bin/snort -c snort.conf -i xl0 database: using the "alert" facility 1458 Snort rules read... 1458 Option Chains linked into 146 Chain Headers 0 Dynamic rules +++++++++++++++++++++++++++++++++++++++++++++++++++ Rule application order: ->activation->dynamic->alert->pass->log --= = Initialization Complete = =-- -*> Snort! <*- Version 2.0.5 (Build 98) By Martin Roesch<EMAIL_ADDRESS>www.snort.org) If snort doesn't show any errors, as depicted here, pat yourself on the back: snort is running! Quit snort by pressing Ctrl-C, and restart it in daemon mode: # /usr/local/bin/snort -c snort.conf -i xl0 -D Now flip on over to the ACID display page in your web browser. You should start to see alerts coming in. Figure 6-6 shows a sample alert listing. Figure 6-6. ACID alertsNote that each detected signature includes a hyperlink to information about that particular type of attack. Snort also keeps track of how many packets matched that signature, the number of unique source and destination addresses, and the time frame between the first and last packet. You can also configure your own alert groups to better organize your results, as shown in Figure 6-7. Figure 6-7. ACID alert groupsACID can also display each rogue packet in intimate detail, as seen in Figure 6-8. Figure 6-8. An ACID packet in detailKeep in mind that you'll probably start getting false positives, depending on the types of traffic on your network. However, these can easily be weeded out by making the appropriate changes to your /usr/local/etc/snort.conf file and the rule files in /usr/local/share/snort. If you start noticing a bunch of alerts that look like Figure 6-9, it's a good indication that some nodes on your network are infected with a virus or worm. Figure 6-9. Suspicious Snort alerts6.7.5 Hacking the HackSnort and ACID have many additional features. For example, you can use your favorite mail transfer agent, such as Sendmail or Postfix, to send out email alerts, and you can create an archive database to store alerts generated by snort. There's even a snort plug-in for the Big Brother System and Network Monitor that can alert you when 30 or more alerts are generated. You can also add additional security to MySQL, Snort, and ACID by creating a nonprivileged snort user and locking down the /usr/local/www/acid directory with the use of a properly configured .htaccess file. Configuration of these features goes beyond the scope of this hack, but I encourage you to read all the documentation included with these applications, as well as the documentation at each application's home page, to find out how you can tailor them to suit your needs. 6.7.6 See Also
|
| < Day Day Up > |


This CIX Forums script will retrieve a file that you would normally have to download using ftp and send it to you via an e-mail message. You will be asked to provide the name of the ftp site where the file can be found, the path of the directory in which it can be found and the name of the file. Your request will be added to a queue and you will receive the file via e-mail when your request has reached the top of the queue.


Age: {{vm.pet.Age}} year(s) old
Description: {{vm.pet.Description}}
Price: {{vm.pet.Price | currency}}
This pet is not for sale


All the resolutions like mobile, tablet, laptop etc have an optimized design based on user experience.
Optimized to have the best code for a better speed and google indexing.
Meta title, Meta descriptions, kewords, OGgraphs, SchemaORG etc. All you need for SEO
Easy to customize the popup and the content of the Privacy Policy page
You can enable or disable this feature or change the whatsapp number in the CMS
All the images and background image are loaded with lazy load so the website will have a better speed.
With this website and CMS you will have the perfect score, the code is optimized 100%
Protect your website from bots that are trying to spam your contact forms / emails.
Very easy to add a photo, just drag and drop the file and copy/paste the URL in any section
Easy to manage the articles or projects or their categories from the CMS.
Niva 2.0 created many concepts designed based on user experience from real sites.
You can easy manage default templates, pages, posts, projects, etc.


Bacon chicken meatloaf frankfurter porchetta drumstick pork salami t-bone landjaeger shank boudin meatball. Tongue fatback pork belly, turducken capicola swine filet mignon ground round.  Ham hock t-bone biltong, leberkas hamburger ribeye chicken short loin filet mignon sausage bacon beef ribs. Ham hock rump pig, leberkas swine short ribs brisket pork loin ground round. Chicken kielbasa ribeye salami jerky rump capicola tongue hamburger ham porchetta.
Topsail doubloon interloper grog blossom rigging piracy hang the jib Barbary Coast spanker salmagundi.  Pieces of Eight measured fer yer chains handsomely galleon red ensign mizzen case shot topgallant rope's end black spot. Ballast pink nipper holystone log shrouds code of conduct stern rope's end bowsprit.  Topsail chantey furl careen jolly boat Yellow Jack keel flogging sutler ballast. Aye booty flogging reef sails Privateer salmagundi quarter yawl topmast fathom. American Main Corsair wench splice the main brace crimp rigging warp boom gangway topgallant.


Pic Metric
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Svyatoslav Okshin
Web UI Developer
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Machine Learning Engineer
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Machine Learning Engineer
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Project Lead


Preverify Command Line
Parameters:
platformhome - platform home filled above
srcdir - source directory of classes to preverify
destdir - destination directory for preverified classes
classpath - platform classpath will be defined on the next wizard step
/ - OS specific directory separator
Parameter formats:
{argument} is a simple replacement, so for example {jadfile} will be replaced by the real path to the jad file.
{argument|command line part} is a condition, if argument is set to some value the command line part will be added to the command line.
Combination of condition and simple replacement is allowed. For example: {jadfile|-Xdescriptor:"{jadfile}"} means that if the jadfile argument contains /myfolder/my.jad then -Xdescriptor:"/myfolder/my.jad" will be added to the command line.


REVIVAL OF THE OLDEST HOTEL IN CAMBRIDGE BY JOHN SIMPSON ARCHITECTS
John Simpson Architects' £30 million revitalization of the University Arms Hotel for Melford Capital Partners is now fully underway. RG Carter has just been appointed as the contractor to carry out the extensive works to this fabulous hotel. The original buildings, defaced in the 1960s, will have these detrimental accretions cleared away and a new classical frontage will restore the hotel's prominence in the city.
John Simpson Architects have been commissioned to carry out a major refurbishment and extension to the University Arms Hotel, the oldest hotel in Cambridge. Originally opened as a coaching inn in the 1840s, the hotel was extended in the 1930s, and then unsympathetically in the 1960s.
Having consulted the local community, a planning application was submitted to City of Cambridge in July 2013. Planning consent was subsequently granted on the 6th November 2013 for the designs, which involved fairly controversial elements such as adding an extra story to the 1930s extension, and in-filling between parts of the historic core of the building. To mitigate this, the design removes unsympathetic additions which are detrimental to the hotel and its surroundings. This is a sensitive intervention within the historic fabric of the hotel.
The University Arms is in an important location in the historic centre of Cambridge, on the old High Street. Overlooking the common, Parker's Piece, the site is constrained on all sides, so that the extension must make use of existing buildings and space. When the works are completed, the 190-bed hotel will be the premier hotel in Cambridge providing first class facilities with excellent new bedrooms, a destination restaurant, bar, gym and conference facilities over 11,800 square metres. The project will enhance the relationship of the hotel with the street and the open space of Parker's Piece.
Furthermore the plans will see an improvement to the traffic flows on Regent Street and Park Terrace with a new and improved servicing plan. The addition of an elegant Porte Cochere to the front of the hotel will utilize its visual language to emphasise that this is a gateway to the city and has the practical benefit of organising the currently confusing and hazardous traffic flow coming into and out of the hotel.
Cambridge has a growing demand from corporate visitors and tourists but an undersupplied hotel market and the city needs to cater for the anticipated additional demand over the next decades.
The hotel is an important building marking one of the main routes into the town centre and acts as the base for many visitors. As a building it has grown and developed to reflect both the success and popularity of the hotel and of Cambridge itself as a city. The work by JSA continues this tradition and signals a new era of posterity as it is intended to be the best hotel in Cambridge.


Before Change
)
return float(output)
file_paths.sort(key=func)
with io.FileIO(manifest_path, "w") as file:
for wav_path in file_paths:
transcript_path = wav_path.replace("/wav/", "/txt/").replace(".wav", ".txt")
sample = os.path.abspath(wav_path) + "," + os.path.abspath(transcript_path) + "\n"
After Change
file_paths = []
wav_files = [os.path.join(dirpath, f)
for dirpath, dirnames, files in os.walk(data_path)
for f in fnmatch.filter(files, "*.wav")]
size = len(wav_files)
counter = 0
for file_path in wav_files:
file_paths.append(file_path.strip())
counter += 1


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| Resource (const upx_byte *ibufstart, const upx_byte *ibufen) |
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| Resource (const upx_byte *p, const upx_byte *ibufstart, const upx_byte *ibufend) |
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void | init (const upx_byte *) |
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unsigned | dirsize () const |
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bool | next () |
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unsigned | itype () const |
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const upx_byte * | ntype () const |
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unsigned | size () const |
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unsigned | offs () const |
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unsigned & | newoffs () |
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upx_byte * | build () |
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bool | clear () |
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void | dump () const |
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unsigned | iname () const |
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const upx_byte * | nname () const |
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The documentation for this class was generated from the following files:


What I do? UI Design Ux Design Branding & Identity Graphic Design Front-end Development App Development


org.apache.hadoop.fs.FutureDataInputStreamBuilder
An interface offering of the Builder pattern for creating Java Future
references to FSDataInputStream
and its subclasses. It is used to initate a (potentially asynchronous) operation to open an existing file for reading.
The FutureDataInputStreamBuilder
interface does not require parameters or or the state of FileSystem
until build()
is invoked and/or during the asynchronous open operation itself.
Some aspects of the state of the filesystem, MAY be checked in the initial openFile()
call, provided they are known to be invariants which will not change between openFile()
and the build().get()
sequence. For example, path validation.
FutureDataInputStreamBuilder bufferSize(int bufSize)
Set the size of the buffer to be used.
FutureDataInputStreamBuilder withFileStatus(FileStatus status)
A FileStatus
instance which refers to the file being opened.
This MAY be used by implementations to short-circuit checks for the file, So potentially saving on remote calls especially to object stores.
Requirements:
status != null
status.getPath().getName()
== the name of the file being opened.The path validation MUST take place if the store uses the FileStatus
when it opens files, and MAY be performed otherwise. The validation SHOULD be postponed until the build()
operation.
This operation should be considered a hint to the filesystem.
If a filesystem implementation extends the FileStatus
returned in its implementation MAY use this information when opening the file.
This is relevant with those stores which return version/etag information, -they MAY use this to guarantee that the file they opened is exactly the one returned in the listing.
The final status.getPath().getName()
element of the supplied status MUST equal the name value of the path supplied to the openFile(path)
call.
Filesystems MUST NOT validate the rest of the path. This is needed to support viewfs and other mount-point wrapper filesystems where schemas and paths are different. These often create their own FileStatus results
Preconditions
status == null or status.getPath().getName() == path.getName()
Filesystems MUST NOT require the class of status
to equal that of any specific subclass their implementation returns in filestatus/list operations. This is to support wrapper filesystems and serialization/deserialization of the status.
FutureDataInputStreamBuilder opt(String key, ...) FutureDataInputStreamBuilder must(String key, ...)
Set optional or mandatory parameters to the builder. Using opt()
or must()
, client can specify FS-specific parameters without inspecting the concrete type of FileSystem
.
Example:
out = fs.openFile(path) .must("fs.option.openfile.read.policy", "random") .opt("fs.http.connection.timeout", 30_000L) .withFileStatus(statusFromListing) .build() .get();
Here the read policy of random
has been specified, with the requirement that the filesystem implementation must understand the option. An http-specific option has been supplied which may be interpreted by any store; If the filesystem opening the file does not recognize the option, it can safely be ignored.
opt()
versus must()
The difference between opt()
versus must()
is how the FileSystem opening the file must react to an option which it does not recognize.
def must(name, value): if not name in known_keys: raise IllegalArgumentException if not name in supported_keys: raise UnsupportedException def opt(name, value): if not name in known_keys: # ignore option
For any known key, the validation of the value
argument MUST be the same irrespective of how the (key, value) pair was declared.
value
is defined in this filesystem specification, validated through contract tests.Checking for supported options must be performed in the build()
operation.
If a mandatory parameter declared via must(key, value)
) is not recognized, IllegalArgumentException
MUST be thrown.
If a mandatory parameter declared via must(key, value)
relies on a feature which is recognized but not supported in the specific FileSystem
/FileContext
instance UnsupportedException
MUST be thrown.
The behavior of resolving the conflicts between the parameters set by builder methods (i.e., bufferSize()
) and opt()
/must()
is as follows:
The last option specified defines the value and its optional/mandatory state.
If the FileStatus
option passed in withFileStatus()
is used, implementations MUST accept all subclasses of FileStatus
, including LocatedFileStatus
, rather than just any FS-specific subclass implemented by the implementation (e.g S3AFileStatus
). They MAY simply ignore those which are not the custom subclasses.
This is critical to ensure safe use of the feature: directory listing/ status serialization/deserialization can result result in the withFileStatus()
argument not being the custom subclass returned by the Filesystem instance’s own getFileStatus()
, listFiles()
, listLocatedStatus()
calls, etc.
In such a situation the implementations must:
status.getPath().getName()
matches the current path.getName()
value. The rest of the path MUST NOT be validated.Even if not values of the status are used, the presence of the argument can be interpreted as the caller declaring that they believe the file to be present and of the given size.
CompletableFuture<FSDataInputStream> build()
Return an CompletableFuture<FSDataInputStream>
which, when successfully completed, returns an input stream which can read data from the filesystem.
The build()
operation MAY perform the validation of the file’s existence, its kind, so rejecting attempts to read from a directory or non-existent file. Alternatively * file existence/status checks MAY be performed asynchronously within the returned CompletableFuture<>
. * file existence/status checks MAY be postponed until the first byte is read in any of the read such as read()
or PositionedRead
.
That is, the precondition exists(FS, path)
and isFile(FS, path)
are only guaranteed to have been met after the get()
called on returned future and an attempt has been made to read the stream.
Thus, if even when file does not exist, or is a directory rather than a file, the following call MUST succeed, returning a CompletableFuture
to be evaluated.
Path p = new Path("file://tmp/file-which-does-not-exist"); CompletableFuture<FSDataInputStream> future = p.getFileSystem(conf) .openFile(p) .build();
The inability to access/read a file MUST raise an IOException
or subclass in either the future’s get()
call, or, for late binding operations, when an operation to read data is invoked.
Therefore the following sequence SHALL fail when invoked on the future
returned by the previous example.
future.get().read();
Access permission checks have the same visibility requirements: permission failures MUST be delayed until the get()
call and MAY be delayed into subsequent operations.
Note: some operations on the input stream, such as seek()
may not attempt any IO at all. Such operations MAY NOT raise exceotions when interacting with nonexistent/unreadable files.
openFile()
options since Hadoop 3.3.3These are options which FileSystem
and FileContext
implementation MUST recognise and MAY support by changing the behavior of their input streams as appropriate.
Hadoop 3.3.0 added the openFile()
API; these standard options were defined in a later release. Therefore, although they are “well known”, unless confident that the application will only be executed against releases of Hadoop which knows of the options -applications SHOULD set the options via opt()
calls rather than must()
.
When opening a file through the openFile()
builder API, callers MAY use both .opt(key, value)
and .must(key, value)
calls to set standard and filesystem-specific options.
If set as an opt()
parameter, unsupported “standard” options MUST be ignored, as MUST unrecognized standard options.
If set as a must()
parameter, unsupported “standard” options MUST be ignored. unrecognized standard options MUST be rejected.
The standard openFile()
options are defined in org.apache.hadoop.fs.OpenFileOptions
; they all SHALL start with fs.option.openfile.
.
Note that while all FileSystem
/FileContext
instances SHALL support these options to the extent that must()
declarations SHALL NOT fail, the implementations MAY support them to the extent of interpreting the values. This means that it is not a requirement for the stores to actually read the read policy or file length values and use them when opening files.
Unless otherwise stated, they SHOULD be viewed as hints.
Note: if a standard option is added such that if set but not supported would be an error, then implementations SHALL reject it. For example, the S3A filesystem client supports the ability to push down SQL commands. If something like that were ever standardized, then the use of the option, either in opt()
or must()
argument MUST be rejected for filesystems which don’t support the feature.
fs.option.openfile.buffer.size
Read buffer size in bytes.
This overrides the default value set in the configuration with the option io.file.buffer.size
.
It is supported by all filesystem clients which allow for stream-specific buffer sizes to be set via FileSystem.open(path, buffersize)
.
fs.option.openfile.read.policy
Declare the read policy of the input stream. This is a hint as to what the expected read pattern of an input stream will be. This MAY control readahead, buffering and other optimizations.
Sequential reads may be optimized with prefetching data and/or reading data in larger blocks. Some applications (e.g. distCp) perform sequential IO even over columnar data.
In contrast, random IO reads data in different parts of the file using a sequence of seek()/read()
or via the PositionedReadable
or ByteBufferPositionedReadable
APIs.
Random IO performance may be best if little/no prefetching takes place, along with other possible optimizations
Queries over columnar formats such as Apache ORC and Apache Parquet perform such random IO; other data formats may be best read with sequential or whole-file policies.
What is key is that optimizing reads for seqential reads may impair random performance -and vice versa.
must()
option, the filesystem MAY ignore it.| Policy | Meaning |
|---|---|
adaptive |
Any adaptive policy implemented by the store. |
default |
The default policy for this store. Generally “adaptive”. |
random |
Optimize for random access. |
sequential |
Optimize for sequential access. |
vector |
The Vectored IO API is intended to be used. |
whole-file |
The whole file will be read. |
Choosing the wrong read policy for an input source may be inefficient.
A list of read policies MAY be supplied; the first one recognized/supported by the filesystem SHALL be the one used. This allows for custom policies to be supported, for example an hbase-hfile
policy optimized for HBase HFiles.
The S3A and ABFS input streams both implement the IOStatisticsSource API, and can be queried for their IO Performance.
Tip: log the toString()
value of input streams at DEBUG
. The S3A and ABFS Input Streams log read statistics, which can provide insight about whether reads are being performed efficiently or not.
Futher reading
adaptive
Try to adapt the seek policy to the read pattern of the application.
The normal
policy of the S3A client and the sole policy supported by the wasb:
client are both adaptive -they assume sequential IO, but once a backwards seek/positioned read call is made the stream switches to random IO.
Other filesystem implementations may wish to adopt similar strategies, and/or extend the algorithms to detect forward seeks and/or switch from random to sequential IO if that is considered more efficient.
Adaptive read policies are the absence of the ability to declare the seek policy in the open()
API, so requiring it to be declared, if configurable, in the cluster/application configuration. However, the switch from sequential to random seek policies may be exensive.
When applications explicitly set the fs.option.openfile.read.policy
option, if they know their read plan, they SHOULD declare which policy is most appropriate.
The default policy for the filesystem instance. Implementation/installation-specific.
sequential
Expect sequential reads from the first byte read to the end of the file/until the stream is closed.
random
Expect seek()/read()
sequences, or use of PositionedReadable
or ByteBufferPositionedReadable
APIs.
vector
This declares that the caller intends to use the Vectored read API of HADOOP-11867 Add a high-performance vectored read API.
This is a hint: it is not a requirement when using the API. It does inform the implemenations that the stream should be configured for optimal vectored IO performance, if such a feature has been implemented.
It is not exclusive: the same stream may still be used for classic InputStream
and PositionedRead
API calls. Implementations SHOULD use the random
read policy with these operations.
whole-file
This declares that the whole file is to be read end-to-end; the file system client is free to enable whatever strategies maximise performance for this. In particular, larger ranged reads/GETs can deliver high bandwidth by reducing socket/TLS setup costs and providing a connection long-lived enough for TCP flow control to determine the optimal download rate.
Strategies can include:
openFile()
operation.Applications which know that the entire file is to be read from an opened stream SHOULD declare this read policy.
fs.option.openfile.length
Declare the length of a file.
This can be used by clients to skip querying a remote store for the size of/existence of a file when opening it, similar to declaring a file status through the withFileStatus()
option.
If supported by a filesystem connector, this option MUST be interpreted as declaring the minimum length of the file:
read()
, seek()
and positioned read calls MAY use a position across/beyond this length but below the actual length of the file. Implementations MAY raise EOFExceptions
in such cases, or they MAY return data.If this option is used by the FileSystem implementation
Implementor’s Notes
fs.option.openfile.length
< 0 MUST be rejected.fs.opt.openfile.length
; the file status values take precedence.fs.option.openfile.split.start
and fs.option.openfile.split.end
Declare the start and end of the split when a file has been split for processing in pieces.
fs.option.openfile.split.end
.fs.option.openfile.split.end
.The split end value can provide a hint as to the end of the input stream. The split start can be used to optimize any initial read offset for filesystem clients.
*Note for implementors: applications will read past the end of a split when they need to read to the end of a record/line which begins before the end of the split.
Therefore clients MUST be allowed to seek()
/read()
past the length set in fs.option.openfile.split.end
if the file is actually longer than that value.
The S3A Connector supports custom options for readahead and seek policy.
| Name | Type | Meaning |
|---|---|---|
fs.s3a.readahead.range |
long |
readahead range in bytes |
fs.s3a.input.async.drain.threshold |
long |
threshold to switch to asynchronous draining of the stream |
fs.s3a.experimental.input.fadvise |
String |
seek policy. Superceded by fs.option.openfile.read.policy |
If the option set contains a SQL statement in the fs.s3a.select.sql
statement, then the file is opened as an S3 Select query. Consult the S3A documentation for more details.
The ABFS Connector supports custom input stream options.
| Name | Type | Meaning |
|---|---|---|
fs.azure.buffered.pread.disable |
boolean |
disable caching on the positioned read operations. |
Disables caching on data read through the PositionedReadable APIs.
Consult the ABFS Documentation for more details.
Here is an example from a proof of concept org.apache.parquet.hadoop.util.HadoopInputFile
reader which uses a (nullable) file status and a split start/end.
The FileStatus
value is always passed in -but if it is null, then the split end is used to declare the length of the file.
protected SeekableInputStream newStream(Path path, FileStatus stat, long splitStart, long splitEnd) throws IOException { FutureDataInputStreamBuilder builder = fs.openFile(path) .opt("fs.option.openfile.read.policy", "vector, random") .withFileStatus(stat); builder.opt("fs.option.openfile.split.start", splitStart); builder.opt("fs.option.openfile.split.end", splitEnd); CompletableFuture<FSDataInputStream> streamF = builder.build(); return HadoopStreams.wrap(FutureIO.awaitFuture(streamF)); }
As a result, whether driven directly by a file listing, or when opening a file from a query plan of (path, splitStart, splitEnd)
, there is no need to probe the remote store for the length of the file. When working with remote object stores, this can save tens to hundreds of milliseconds, even if such a probe is done asynchronously.
If both the file length and the split end is set, then the file length MUST be considered “more” authoritative, that is it really SHOULD be defining the file length. If the split end is set, the caller MAY ot read past it.
The CompressedSplitLineReader
can read past the end of a split if it is partway through processing a compressed record. That is: it assumes an incomplete record read means that the file length is greater than the split length, and that it MUST read the entirety of the partially read record. Other readers may behave similarly.
Therefore
FileStatus
or in fs.option.openfile.length
SHALL set the strict upper limit on the length of a filefs.option.openfile.split.end
MUST be viewed as a hint, rather than the strict end of the file.Standard and non-standard options MAY be combined in the same openFile()
operation.
Future<FSDataInputStream> f = openFile(path) .must("fs.option.openfile.read.policy", "random, adaptive") .opt("fs.s3a.readahead.range", 1024 * 1024) .build(); FSDataInputStream is = f.get();
The option set in must()
MUST be understood, or at least recognized and ignored by all filesystems. In this example, S3A-specific option MAY be ignored by all other filesystem clients.
Not all hadoop releases recognize the fs.option.openfile.read.policy
option.
The option can be safely used in application code if it is added via the opt()
builder argument, as it will be treated as an unknown optional key which can then be discarded.
Future<FSDataInputStream> f = openFile(path) .opt("fs.option.openfile.read.policy", "vector, random, adaptive") .build(); FSDataInputStream is = f.get();
Note 1 if the option name is set by a reference to a constant in org.apache.hadoop.fs.Options.OpenFileOptions
, then the program will not link against versions of Hadoop without the specific option. Therefore for resilient linking against older releases -use a copy of the value.
Note 2 as option validation is performed in the FileSystem connector, a third-party connector designed to work with multiple hadoop versions MAY NOT support the option.
Hadoop MapReduce will automatically read MR Job Options with the prefixes mapreduce.job.input.file.option.
and mapreduce.job.input.file.must.
prefixes, and apply these values as .opt()
and must()
respectively, after remove the mapreduce-specific prefixes.
This makes passing options in to MR jobs straightforward. For example, to declare that a job should read its data using random IO:
JobConf jobConf = (JobConf) job.getConfiguration() jobConf.set( "mapreduce.job.input.file.option.fs.option.openfile.read.policy", "random");
An example of a record reader passing in options to the file it opens.
public void initialize(InputSplit genericSplit, TaskAttemptContext context) throws IOException { FileSplit split = (FileSplit)genericSplit; Configuration job = context.getConfiguration(); start = split.getStart(); end = start + split.getLength(); Path file = split.getPath(); // open the file and seek to the start of the split FutureDataInputStreamBuilder builder = file.getFileSystem(job).openFile(file); // the start and end of the split may be used to build // an input strategy. builder.opt("fs.option.openfile.split.start", start); builder.opt("fs.option.openfile.split.end", end); FutureIO.propagateOptions(builder, job, "mapreduce.job.input.file.option", "mapreduce.job.input.file.must"); fileIn = FutureIO.awaitFuture(builder.build()); fileIn.seek(start) /* Rest of the operation on the opened stream */ }
FileContext.openFile
From org.apache.hadoop.fs.AvroFSInput
; a file is opened with sequential input. Because the file length has already been probed for, the length is passd down
public AvroFSInput(FileContext fc, Path p) throws IOException { FileStatus status = fc.getFileStatus(p); this.len = status.getLen(); this.stream = awaitFuture(fc.openFile(p) .opt("fs.option.openfile.read.policy", "sequential") .opt("fs.option.openfile.length", Long.toString(status.getLen())) .build()); fc.open(p); }
In this example, the length is passed down as a string (via Long.toString()
) rather than directly as a long. This is to ensure that the input format will link against versions of $Hadoop which do not have the opt(String, long)
and must(String, long)
builder parameters. Similarly, the values are passed as optional, so that if unrecognized the application will still succeed.
This is from org.apache.hadoop.util.JsonSerialization
.
Its load(FileSystem, Path, FileStatus)
method * declares the whole file is to be read end to end. * passes down the file status
public T load(FileSystem fs, Path path, status) throws IOException { try (FSDataInputStream dataInputStream = awaitFuture(fs.openFile(path) .opt("fs.option.openfile.read.policy", "whole-file") .withFileStatus(status) .build())) { return fromJsonStream(dataInputStream); } catch (JsonProcessingException e) { throw new PathIOException(path.toString(), "Failed to read JSON file " + e, e); } }
Note: : in Hadoop 3.3.2 and earlier, the withFileStatus(status)
call required a non-null parameter; this has since been relaxed. For maximum compatibility across versions, only invoke the method when the file status is known to be non-null.


Now that you have completed all the tutorials, lets move on to the quiz section to see how deep is you understanding about reading time.
Good Luck !


137 min | actionthriller |
Deckard Shaw seeks revenge against Dominic Toretto and his family for his comatose brother.
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This is the 1.1 release of the Axis SOAP library.
This release is primarily an upgrade to fix a number of bugs in the 1.0 release. Since it took longer than we expected, you'll also find a bunch of new features in there.
We still have a *lot* of open bugs on the books, so please realize that this is not a completely polished work yet. After 1.1 ships we hope / plan to do a lot of work cleaning things up and adding some much-needed functionality which is currently missing, in hopes of releasing a much better 1.2 release in the not-too-distant future.
We say this a lot, but it's worth repeating - you can help! If you've got coding skill, interest, and a little free time, we'd love to have you join the Axis community and help make the product better - see below.
Click to read the 1.1 change log.
This release is intended to be 100% compliant with the JAX-RPC and SAAJ specifications from Sun. The Axis code has successfully passed the all of the JAX-RPC and SAAJ TCK (Technology Compatibility Kit) tests.
Please check out the included documentation and the FAQ for more information.
Coding, testing, and helping to answer questions on axis-user are all greatly appreciated. We particularly encourage you to submit improvements to the documentation, however large or small and in any format, to<EMAIL_ADDRESS>Also, interoperability is always a concern, so please report all replicable bugs.
Thanks for your interest in Axis!
-- The Axis Development Team