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Created by Fang on February 16, 2012 12:27:55    Last update: February 16, 2012 12:34:58
Here are some ways to run a main method using Maven: Use the exec plugin: mvn exec:java -Dexec.mainClass="com.example.App" or, with arguments: mvn exec:java -Dexec.mainClass="com.example.App" -... Attach it to a build phase with the build element: <build> <plugins> <plugin> ... If you want to run main from Maven, it's probably just some test code. You are better off just to write a test case, or call the main method from a test class: package com.example; import junit.framework...
Created by Fang on November 21, 2011 16:30:56    Last update: December 07, 2011 08:54:32
This is a series of notes on building custom JSF 2.0 facelet taglibs, ordered from the simplest to the less simple. Hopefully it can help you to get started on how to build custom taglibs for JSF. A simple JSF facelets taglib example The simplest taglib I can think of. Using EL expression with a custom tag Make tag attributes dynamic. Mixing custom tag with facelet ui taglibs Discover things you might run into when you get into more details. Which EL context to use? Using the wrong EL context can lead to subtle bugs. JSF facelet taglib backed by a UI component A UIComponent can be a tag handler, without being TagHandler . Using tag handler, UI component and renderer with a JSF facelet...
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 22, 2011 20:43:31    Last update: October 22, 2011 20:45:13
The only explanation of why some Java EE API classes are stripped off methods implementations I can find is this JBos forum post: What's the cause of this exception: java.lang.ClassFormatError: Absent Code? which also provides some workarounds for these crippled API classes. The explanation offered was: When one compiles, they want to run as well. By the way, we have been promoting full set of Java EE APIs which can only be used for compilation - they are stripped off method details. That way, user can't take those artifacts and try to use it in runtime. Honestly, I don't see any logic in those statements. This is the only place any such explanation is offered. Yes only from this JBos forum post! There's no public...
Created by Fang on October 22, 2011 19:51:05    Last update: October 22, 2011 20:31:48
I built a very basic JSF application and deployed to Tomcat 7.0.22, but it failed with this error: Caused by: java.lang.ClassFormatError: Absent Code... That looks weird and I wasn't able to find a sensible explanation! So I copied the jsf-api-2.1.jar , which was downloaded from the java.net Maven repository by Maven, into a temp folder. And tested it with this simple program: public class ClassFormatErrorTest { public ... I also copied servlet-api.jar from Tomcat's lib folder to the temp folder. Sure enough it failed with the same error: C:\tmp>java -cp .;jsf-api-2.1.jar;servlet-api.jar ... But when I replaced the javax.faces.webapp.FacesServlet class with one I compiled from source, the error disappears! Conclusions: The jar file jsf-api-2.1.jar from java.net Maven repository is good for compilation only (cannot be used...
Created by freyo on September 09, 2011 11:43:36    Last update: September 09, 2011 11:45:45
When you run automated Android tests with Eclipse or from the command line, you get text output, which isn't good for reporting purposes. If you run a large set of test cases with automated build, the text report isn't very helpful. Fortunately, Android CTS generates test reports in XML with accompanying XSL to make it look nice in a browser. To run your own tests with Android CTS: Download Android CTS Make a new directory MyRepository under android-cts , alongside the existing repository directory. Copy host_config.xml from repository to MyRepository Create directory plans under MyRepository , add a test plan ( MyTests.xml ): <?xml version="1.0" encoding="UTF-8"?> <TestPla... Create directory testcases under MyRepository . Copy TestDeviceSetup.apk from repository/testcases to MyRepository/testcases Under MyRepository/testcases , create a test...
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 alfa on June 07, 2011 11:34:26    Last update: June 07, 2011 11:36:37
This is an example that uses dynamic proxies to trace method calls (in logging) and print out elapsed times for them. Because dynamic proxies can only be generated for interfaces, the service classes must be implemented with interface-implementation pairs. Create services A and B. A.java : public interface A { public void service1()... AImpl.java : import java.util.Random; public class AImpl... B.java : public interface B { public void service1()... BImpl.java : public class BImpl implements B { public vo... The call trace proxy: import java.lang.reflect.*; class TraceProx... The performance proxy: import java.lang.reflect.*; class Performan... The service factory: import java.lang.reflect.*; public class Se... The test class: public class Test { public static void main... The output: Entering AImpl.service1 Entering BImpl.service1... The above example has no information...
Created by alfa on June 02, 2011 15:26:37    Last update: June 02, 2011 15:26:37
While doing some Java reflection code, I noticed the method Class.isSynthetic() , which the JavaDoc says returns " true if and only if this class is a synthetic class as defined by the Java Language Specification". However, there's no definition of "synthetic class" in the JLS ! The only thing that I can find that remotely resembles a definition is in the JVM spec , where it defines the synthetic attribute : "The Synthetic attribute is a fixed-length attribute in the attributes table of ClassFile (§4.1), field_info (§4.5), and method_info (§4.6) structures. A class member that does not appear in the source code must be marked using a Synthetic attribute." By this definition, a default constructor, which does not appear in the source code, should...
Created by jinx on May 03, 2011 08:56:55    Last update: May 03, 2011 08:57:54
These error level constants are defined in PHP : Constant Value Description E_ERROR 1 Fatal run-time errors. Execution of the script is halted. E_WARNING 2 (1<<1) Run-time warnings (non-fatal errors). Execution of the script is not halted. E_PARSE 4 (1<<2) Compile-time parse errors. Parse errors should only be generated by the parser. E_NOTICE 8 (1<<3) Notices. Indicate that the script encountered something that could indicate an error, but could also happen in the normal course of running a script. E_CORE_ERROR 16 (1<<4) Fatal errors that occur during PHP's initial startup. This is like an E_ERROR, except it is generated by the core of PHP. E_CORE_WARNING 32 (1<<5) Warnings (non-fatal errors) that occur during PHP's initial startup. This is like an E_WARNING, except it is generated...
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