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Created by Fang on January 28, 2012 13:24:09
Last update: January 28, 2012 13:31:22
This is a simple JSP custom tags library with tag body. Just like the JSF counterpart , it splits a string and repeats the body for each word, i.e., with this markup:
<%@ taglib uri="http://custom.tag.com/demo" prefix...
output:
<html>
<body>
<p>Hello Tigger!</p>
<p>H...
With Maven, this is the directory structure:
./src
./src/main
./src/main/resources
./s...
There are three files to write:
pom.xml :
<project xmlns="http://maven.apache.org/POM/4.0.0"...
src/main/java/tagdemo/IterateTag.java :
package tagdemo;
import java.io.IOException...
src/main/resources/META-INF/demotag.tld :
<?xml version="1.0" encoding="UTF-8"?>
<!DO...
Build with:
mvn clean install
To use it as a dependency in other Maven projects:
<dependency>
<groupId>tag-demo</groupId>
...
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 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 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 Dr. Xi on June 21, 2011 15:41:51
Last update: June 22, 2011 11:33:36
Demo code for CSV parsing with Apache Commons CSV parser .
Java code:
import java.io.*;
import org.apache.commons.csv...
Test with a simple CSV file:
psmith01,CLASS2B,Peter Smith 1,YEAR2,1,N,ADVANCED,...
Result:
Line 1 has 11 values:
|psmith01|
|CLASS2B|...
The parser worked correctly.
Test with a more complicated CSV file:
"psmith01 abc", "CLASS2B " , " Peter...
Result:
Line 1 has 4 values:
|psmith01 abc|
|CLASS...
The third line is invalid input, but throwing a Java IOException is a bit grave. Also, the parser is not able to escape a backslash.
Add a new line in item two:
"One", "Two
", "Three"
Result:
Line 2 has 3 values:
|One|
|Two
|
|...
Created by Dr. Xi on March 28, 2011 20:51:30
Last update: March 28, 2011 20:53:46
HTTP basic authentication is just Base64 encoded user name and password passed in as the Authorization header. So the following code works:
// encode user name and password
String credent...
However, since JDK 1.2, there's a more Java friendly way:
Authenticator.setDefault(new Authenticator() {
...
Test code:
import java.net.*;
import java.io.*;
pub...
Created by nogeek on November 04, 2010 20:00:15
Last update: November 05, 2010 14:38:43
Following are some bugs in the Xalan jar shipped with JBoss 5.1.0 GA and JBoss 6.0. The Xalan jar file is located in jboss-5.1.0.GA/lib/endorsed ( %JBOSS_HOME%/common/lib for JBoss 6.0).
Test xml:
<?xml version="1.0" encoding="ISO-8859-1"?>
...
Test xsl:
<?xml version="1.0" encoding="ISO-8859-1"?>
<xs...
XSLT Java code:
import org.w3c.dom.*;
import javax.xml.parsers....
DateUtil.java
import java.util.Date;
public class DateUti...
XSLT output:
Transformer Factory class: class org.apache.xalan....
Apparently, the output is wrong. The string "A test event" should not have been displayed.
Created by Dr. Xi on August 27, 2010 22:35:53
Last update: August 27, 2010 22:35:53
This example decompresses a gzip compressed file with java.util.zip.GZIPInputStream . The input is assumed to be Base64 encoded after being gzipped (such would be the case when binary data is transmitted within an XML file).
You don't need the Base64InputStream if the data is not Base64 encoded.
import java.io.*;
import java.util.zip.GZIPInpu...
Created by Dr. Xi on August 24, 2010 21:59:22
Last update: August 24, 2010 21:59:22
This class decodes a Base64 encoded file with the Apache commons codec package:
import java.io.*;
import org.apache.commons.cod...
Created by voodoo on July 30, 2010 14:53:33
Last update: July 30, 2010 14:54:52
The -d switch for cURL sends HTTP POST with data from the command line. To verify the data being posted, this is a CGI script that echos the data back:
#!C:/perl/bin/perl.exe ## ## echo -- echos ... Examples: POST data from command line: C:\>curl -d input1=value1^&input1=value2 http://lo... POST data from stdin (with @ before the - symbol): C:\>curl -d @- http://localhost/cgi-bin/echo.pl ... POST data from a file (with @ before the - symbol and input redirect): C:\tmp>cat data.txt abcd 1234 xyz ... For some reason, @ with file name didn't work as expected: C:\tmp>curl -d @data.txt http://localhost/cgi-bin/... One thing to notice is that cURL removes the new line characters when posting (thus the echo back is only one line instead of three). This can...
