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Created by Fang on January 04, 2012 09:54:05
Last update: January 04, 2012 09:54:05
There are two ways to validate a form with JSF: jsf validation on the page with <f:validate...> tags (for example: <f:validateLength> , <f:validateRegex> , etc.), or JSR303 bean validation. This note is about how to customize messages for JSR303 bean validation. The validation message is specified in the message attribute for each validation annotation type. The mesage attribute is not a literal string, but a string that is interpolated in various ways. For example, the default validation message for AssertFalse is {javax.validation.constraints.AssertFalse.message} , which is replaced with the corresponding string in ValidationMessages.properties (or ValidationMessages_tr.properties , ValidationMessages_es.properties , depending on the locale). This is the contents of ValidationMessages.properties in the hibernate validator reference implementation:
javax.validation.constraints.AssertFalse.message =... To customize the messages, just provide the new value in...
Created by Fang on November 28, 2011 21:04:15
Last update: November 28, 2011 21:04:15
Some innocent looking JavaScript may cause a fatal error in a Facelet page. For example:
<script type="text/javascript">
if (items.lengt...
or
<script type="text/javascript">
// jQuery code ...
Because Facelet is strict XML, therefore, < and > must be escaped.
There are several ways to deal with this:
Do not embed JS code directly in the page. Put the code in .js files and include it in the page with the src attribute.
Put JS code in a CDATA section:
<h:outputScript target="head">
<![CDATA...
Use XML entities:
<script type="text/javascript">
// jQuery code ...
Created by Fang on November 22, 2011 10:40:16
Last update: November 22, 2011 10:40:16
This is an example that uses tag handler, UI component and renderer together to support a custom taglib. The main purpose is to show how these components play together.
The tag renders
<ui:param name="extra" value="el interpreted"/>
...
as
<h3>my:foreach</h3>
<ul class="css class" extra...
These are the files:
The tag handler ( src/main/java/com/example/ForeachTagHandler.java ):
package com.example;
import java.util.Map;
...
The UI component ( src/main/java/com/example/UIForeach.java ):
package com.example;
import java.io.IOExcep...
The renderer ( src/main/java/com/example/ForeachRenderer.java ):
package com.example;
import java.io.IOExcep...
Faces config ( src/main/resources/META-INF/faces-config.xml ):
<?xml version="1.0" encoding="UTF-8"?>
<faces-c...
Taglib config ( src/main/resources/META-INF/foreach.taglib.xml ):
<?xml version="1.0" encoding="UTF-8"?>
<facelet...
Created by Fang on November 08, 2011 20:55:00
Last update: November 21, 2011 18:19:44
In the simple taglib example , I used a tag handler class to implement a taglib. This is an example to implement a taglib with a UI component. The purpose is to use a custom tag to split a string and print each part in a separate paragraph, i.e., print
<p>john</p> <p>steve</p> <p>mike</p> with custom tag <my:foreach> : <my:foreach var="who" value="john steve mike"> ... These are the files: pom.xml <project xmlns="http://maven.apache.org/POM/4.0.0"... src/main/java/com/example/UIForeash.java : package com.example; import java.io.IOExcep... src/main/resources/META-INF/faces-config.xml : <?xml version="1.0" encoding="UTF-8"?> <faces-c... src/main/resources/META-INF/foreach.taglib.xml : <?xml version="1.0" encoding="UTF-8"?> <facelet... How to use: Put the JAR file generated by the above project in the WEB-INF/lib folder of the web app. If the web app is a Maven project, just add the taglib project as a dependency:...
Created by magnum on September 27, 2011 13:57:23
Last update: October 03, 2011 13:02:34
After an IPSec connection is established, all traffic between the network interfaces named in /etc/ipsec.conf are tunneled through IPSec. And only the protocols and ports listed in /etc/ipsec.conf are allowed. For example, if you were able to ssh to the server, after IPSec connection ssh is no longer working if port 22 is not listed. Assume that you set up IPSec tunnel between the hosts 192.168.0.1 and 192.168.0.101 , these tests will show that the IPSec connection is successfully working. Before bringing up IPSec connection If IPSec connection is already established, bring it down:
# ipsec auto --down TCP8080-PSK-CLIENT Monitor server port 8080 with tcpdump ( 192.168.0.1 ): # tcpdump -i eth0 port 8080 -X On server side ( 192.168.0.1 ), listen on port 8080:...
Created by Dr. Xi on September 30, 2011 15:34:47
Last update: September 30, 2011 15:34:47
A naive try would be something like this:
$ nc -l 8082 | nc remote_host 80 Yes, it does forward the request from local port 8082 to remote_host:80 , but the response is dumped to stdout , not routed back to the client as expected. Using a named pipe makes it work: $ mkfifo backpipe $ nc -l 8082 0<backpipe | nc ... Use tee to get a glimpse of the response through the pipe (I wasn't able to find a way to dump the request): $ nc -k -l 8082 0<backpipe | nc localhost 80 | tee... The GNU netcat has a different syntax than the stock nc . It also supports different switches. To listen to port 1234: $ netcat -l -p 1234...
Created by magnum on September 11, 2011 19:46:09
Last update: September 11, 2011 19:46:09
A pair of C functions convert between an Internet address and a string (ASCII):
#include <arpa/inet.h>
/*
* Returns a poin...
However , these functions do not support IPv6. The new pair is:
#include <arpa/inet.h>
/* Convert a Internet ad...
Examples:
#include <sys/socket.h>
#include <netinet/in.h>...
Created by freyo on August 31, 2011 15:49:54
Last update: August 31, 2011 15:49:54
Got this error while trying to build Android app:
[apkbuilder] Creating AppInfo-debug-unaligned.ap...
Solution:
Delete the Android debug keystore:
$ rm ~/.android/debug.keystore
Build again:
$ ant debug
The new key is valid for 30 years (keystore password is 'android'):
$ keytool -list -v -keystore ~/.android/debug.keys...
Created by alfa on July 01, 2011 13:16:12
Last update: July 01, 2011 13:16:12
This is a simple doclet that prints all public methods and their parameter names and types.
Code
import com.sun.javadoc.*;
public class List...
Compile
javac -cp $JAVA_HOME/lib/tools.jar:. ListMethodsDo...
Use
javadoc -doclet ListMethodsDoclet -sourcepath /pat...
Created by James on May 01, 2011 21:57:33
Last update: May 01, 2011 21:57:33
Both visibility:hidden and display:none hides an element in the DOM. But elements with visibility:hidden still takes up space, while display:none does not.
Example (click the divs to hide or show):
<!doctype html>
<html>
<head>
<style t...