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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 Fang on September 07, 2009 20:44:15    Last update: November 03, 2011 14:43:19
Step 1: Repackage a web app as EAR A Java EE application is a multimodule Maven project. At the very least you'll need to package a WAR and an EAR. To get started, I'll simply re-package the simple webapp as an EAR. Create a directory named javaee-app Copy the webapp from here to javaee-app . Rename struts1app to webapp . Create pom.xml under javaee-app : <project> <modelVersion>4.0.0</modelVersion>... Create a directory named ear under javaee-app . Create pom.xml under ear : <project> <modelVersion>4.0.0</modelVersion>... Modify pom.xml in the webapp directory so that it looks like this: <project> <modelVersion>4.0.0</modelVersion> ... Build with " mvn package " in the javaee-app directory. You can see that ear-1.0.ear is successfully generated in javaee-app/ear/target . Maven successfully resolves dependencies between the sub-projects....
Created by Fang on October 28, 2011 13:49:40    Last update: October 30, 2011 19:23:25
This is a simple example to demonstrate the templating power of JSF facelets. If you've used struts tiles before, you'll recognize the simplicity of templating with facelets. I've stripped out everything else except the pages themselves, just to put our focus on facelets. This is a Maven based project, and you need Tomcat (or any servlet container) to run the resulting webapp. To begin with this is the list of files: ./pom.xml ./src/main/webapp/home.xhtml ./src... I left faces-config.xml in there for completeness sake, it may not be needed. The Maven POM ( pom.xml ): <?xml version="1.0" encoding="UTF-8"?> <project... Web app configuration ( WEB-INF/web.xml ): <?xml version="1.0" encoding="UTF-8"?> <web-app... Empty WEB-INF/faces-config.xml : <?xml version="1.0" encoding="UTF-8"?> <!-- Thi... index.jsp is simply a redirect to home.jsf : <% response.sendRedirect("home.jsf"); %>...
Created by Dr. Xi on November 23, 2010 20:20:01    Last update: March 01, 2011 13:38:51
I tried to find a GZIP compression servlet filter to compress a large log file that we send down to the browser. Most of the implementations I found were overly complicated and many buggy. This is a simple implementation that worked for me. The filter: package filter.demo; import java.io.*; i... Config web.xml : <filter> <filter-name>gzipFilter</filte... The ugly anonymous inner class could have been avoided if the servlet API did not insist on ServletResponse.getOutputStream returning the bogus ServletOutputStream class (instead of the plain OutputStream ). Additional Note: In an earlier version of this filter, the gzip headers were added in doFilter , like this: // This is NOT good! if (supportsGzip) { ... It turned out that the ServletResponse methods sendError bypasses the gzip...
Created by Dr. Xi on September 17, 2010 21:29:47    Last update: September 17, 2010 21:31:43
With JBoss (Tomcat?), the servlet container always appends the default charset ISO-8859-1 to the Content-Type header of a JSP response. For example, if you are using JSP to render PDF and put the following declaration at the top of the JSP: <%@ page contentType="application/pdf"%> These would be the headers in the HTTP response (notice that charset=ISO-8859-1 was appended to Content-Type ): HTTP/1.1 200 OK Server: Apache-Coyote/1.1 X-... And the output would be truncated a few bytes before non-ASCII characters were encountered, without any error messages ! Maybe you don't intend to output binary files with JSP, but still your response would be truncated without warning if the page happens to contain any non-ASCII characters (when the charset is the default charset=ISO-8859-1 ). However, if you...
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...
Created by Fang on September 07, 2009 16:39:37    Last update: September 07, 2009 18:43:04
It's easiest to use the archetype plugin to start a new Maven project. I'll use struts 1 as example since it's not in the built-in archetypes for archetype:generate . Generate a simple webapp with archetype:generate : C:\work\maven>mvn archetype:generate -DarchetypeAr... It generates a directory structure like this: struts1app struts1app/pom.xml struts1app/src... with a simple POM: <project xmlns="http://maven.apache.org/POM/4.0.0"... Create settings.xml in $HOME/.m2 , add Java.net repository for Java EE dependencies: <?xml version="1.0" encoding="UTF-8"?> <setting... Add Java EE and Struts dependencies in pom.xml . Note that the Java EE dependency has scope provided , meaning that the web app container provides the jars, therefore we don't need to bundle them with our war fie. <project xmlns="http://maven.apache.org/POM/4.0.0"... Create a directory named java under main , create the Struts form and...
Created by Dr. Xi on December 12, 2007 20:30:01    Last update: December 12, 2007 20:32:23
This is a script to tail a log file through the web browser. It uses AJAX, apache web server, mod_python, UNIX utilities tail (requires the --lines switch) and wc . The log file may reside on the web server or any other host accessible from the web server through SSH. Although it's written in python, it should be easy to port to other languages such as Perl. Apache httpd.conf : LoadModule python_module modules/mod_python.so ... Python script: import time, os from os.path import basename ...