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Created by Fang on December 06, 2011 19:03:25    Last update: December 07, 2011 08:54:11
Our custom tag, as implemented in the previous note , is broken when a template is used. Create a template file ( home-template.xhtml ): <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Stric... and a test page that uses it ( home.xhtml ): <?xml version="1.0" encoding="UTF-8"?> <ui:comp... Then request the page with URL: http://localhost:8080/facelet-demo/home.jsf?name=Jack . You'll find that our hello tag works inside ui:repeat but fails to get the value defined by ui:param ! What's the problem? Our hello tag implementation evaluated the EL with the wrong EL context! This is the corrected implementation: package com.example; import java.io.IOExcep...
Created by freyo on September 07, 2011 16:46:14    Last update: September 07, 2011 19:23:00
The Android unit test framework is based on JUnit 3 , not JUnit 4. Test cases have to extend junit.framework.TestCase or a subclass (such as android.test.InstrumentationTestCase ). Tests are identified by public methods whose name starts with test , not methods annotated with @Test (as in JUnit 4). An Android test suite is packaged as an APK, just like the application being tested. To create a test package, first you need to identify the application package it is testing. Google suggests to put the test package source in a directory named tests/ alongside the src/ directory of the main application. At runtime, Android instrumentation loads both the test package and the application under test into the same process. Therefore, the tests can invoke methods on...
Created by freyo on April 12, 2011 15:13:32    Last update: May 03, 2011 15:20:55
Create new project $ tools/android create project \ > --package co... Edit res/values/string.xml , add strings for the main screen. <?xml version="1.0" encoding="utf-8"?> <resourc... Add widgets to main layout ( res/layout/main.xml ). <?xml version="1.0" encoding="utf-8"?> <LinearL... Edit src/com/android/apkinfo/GetAPKPermissions.java and change contents to: package com.android.apkinfo; import android... Install the debug package to the emulator: ant install The screen should look like: Add display permissions activity. Start by creating a new layout res/layout/display_permissions.xml : <?xml version="1.0" encoding="utf-8"?> <LinearL... Add the strings used by the new Activity ( res/values/strings.xml ): <?xml version="1.0" encoding="utf-8"?> <resourc... Add the Display Permissions Activity ( src/com/android/apkinfo/DisplayPermissions.java ): package com.android.apkinfo; import android... Change src/com/android/apkinfo/GetAPKPermissions.java to invoke the Display Permissions Activity: package com.android.apkinfo; import android... Declare Display Permissions Activity in AndroidManifest.xml : <?xml version="1.0" encoding="utf-8"?> <manifes......
Created by freyo on April 18, 2011 15:08:21    Last update: April 18, 2011 15:12:20
Generate android project $ ~/android-sdk-linux_86/tools/android create proj... Create XML file res/xml/books.xml : <?xml version="1.0"?> <catalog> <book id=... Edit layout ( res/layout/main.xml ): <?xml version="1.0" encoding="utf-8"?> <Lin... Edit code ( src/com/android/xmlres/XMLResource.java ): package com.android.xmlres; import java.io.... Change activity label from app_name to booklist ( AndroidManifest.xml ): <?xml version="1.0" encoding="utf-8"?> <manifes... Add value for string resource ( res/values/string.xml ): <?xml version="1.0" encoding="utf-8"?> <resourc... Deploy and test: ant install
Created by Fang on March 23, 2010 03:50:11    Last update: August 18, 2010 21:59:52
This is a simple web application with a single servlet and a single JSP page. It is intended to be a test bed for JSTL tags. You may want to store all syntax, rules, and exceptions in your head, but in my opinion nothing beats a simple test program that allows you play with it all you want. So here it is (build with Maven ). Prerequisites: Maven: http://maven.apache.org/ . You don't need any prior knowledge of Maven, but you need to install the binary. JBoss: http://jboss.org/jbossas/downloads/ , or Tomcat: http://tomcat.apache.org/ if you don't run the SQL tests. You need to know how to deploy a web application (shh! Don't tell your boss it's just copying a file to the deployment folder). Steps: The directory...
Created by Fang on April 02, 2010 21:45:47    Last update: July 17, 2010 02:55:06
This is built upon the simple test application for JSTL , which contained a single servlet and a single JSP page. If I want to use it to test all available JSTL tags, the servlet and JSP page would be too complicated. Instead, I want to group the JSTL tags into separate JSP pages and display each group based on the requested URL. For example, if the URL ends with /CoreBasic , I'll display a page that contains the basic core tags; if the URL ends with /I18N , I'll display a page that contains the internationalization tags (e.g., <fmt:message> ). Furthermore, I want to delegate the handling of each group of tags to separate Java classes. This is the application I'll use for the...
Created by Fang on April 01, 2010 22:24:58    Last update: April 02, 2010 02:49:38
In this note I'll show you how to create and package a JSP custom tag. The purpose of this tag is to display a random splash image for a home page, among a set of images. We should be able to add or delete candidate splash images from the WAR archive without the need to change the JSP. This is the intended use of the tag: <%@ taglib uri="http://custom.tag.com/demo" prefix... In the above example you provide a set of images named splash*.png (e.g., splash1.png, spalsh2.png, ...), and the tag will pick a random one to display when the JSP is rendered. Let's get started. I'll use Maven for this purpose. Create the standard Maven directory structure ./pom.xml ./src ./src/main ./src/main/jav... pom.xml <project xmlns="http://maven.apache.org/POM/4.0.0"... SplashTag.java package tagdemo; import java.util.ArrayList......
Created by Dr. Xi on September 20, 2009 16:52:19    Last update: March 22, 2010 01:28:49
When I assemble a session bean without the proprietary deployment descriptor ( orion-ejb-jar.xml ), OC4J generates one like this (as can be seen from the OC4J management console): <?xml version="1.0" encoding="utf-8"?> <ori... So I use this code to lookup the EJB: import javax.naming.Context; import javax.namin... OC4J throws ClassCastException : java.lang.ClassCastException: com.evermind[Oracle ... The JNDI browser (OC4J container home -> Administration -> JNDI browser) shows that the name simpleEjb_SimpleBeanLocal is bound to: com.evermind.server.ejb.StatelessSessionDefaultLocalHomeImpl Solution: Change the local name in the OC4J generated orion-ejb-jar.xml to simpleEjb_SimpleBeanLocal2 and put it in the EJB package. Redeploy. The JNDI browser shows that simpleEjb_SimpleBeanLocal is still bound to com.evermind.server.ejb.StatelessSessionDefaultLocalHomeImpl . But simpleEjb_SimpleBeanLocal2 is bound to the right proxy: SimpleBean_LocalProxy_5f4b5e5 .
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 ...