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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 lokf on January 13, 2012 14:10:42
Last update: January 13, 2012 14:10:42
For some reason I don't know writing to files in Android is very complicated and tedious. Here is some code for those who might need it. Apps should write in the SD in the directory /Android/data/package_name/files/ so that it is deleted with the app uninstall. package randomname; import java.io.BufferedOutputStream; import java.io.File; import java.io.FileInputStream; import java.io.FileNotFoundException; import java.io.FileOutputStream; import java.io.FileWriter; import java.io.IOException; import java.io.OutputStream; import java.io.OutputStreamWriter; import java.nio.ByteBuffer; import android.content.Context; import android.os.Environment; import android.util.Log; public class FileIOLibrary { String packageName; boolean mExternalStorageAvailable = false; boolean mExternalStorageWriteable = false; FileIOLibrary(String packageNamep) { this.packageName=packageNamep; } public boolean isExternalStorageAvailable() { updateExternalStorageState(); return mExternalStorageAvailable; } public boolean isExternalStorageWritable() { updateExternalStorageState(); return mExternalStorageWriteable; } /** * writes the current state of SD card to the corresponding variables */ void updateExternalStorageState() {...
Created by freyo on May 20, 2011 09:25:20
Last update: May 23, 2011 12:11:42
The javax.xml.crypto and javax.xml.crypto.dsig packages are not available in Android (as of version 2.3). Therefore, standard Java API does not work. But you can use the Apache Santuario library to do that. Here are the steps:
Download the xml security source distribution (curently version 1.4.4).
Build with ant.
Create your own library jar (only the apache classes, no javax):
jar -cf xmlsec-1.4.4.jar -C build/classes org
Copy xmlsec-1.4.4.jar to the libs directory of your Android project.
Here's the Java code:
import java.io.*;
import javax.xml.parsers.*;
...
Created by freyo on May 17, 2011 11:13:17
Last update: May 17, 2011 11:13:17
This is an odd-ball content provider in that it doesn't provide database records, but provides a resource as a stream. It can be used to provide media files or XML resources. Start the project with:
tools/android create project --package com.android... Create assets directory and add an XML file ( assets/demo.xml ): <? xml version="1.0" encoding="UTF-8"?> <people... Edit the layout ( res/layout/main.xml ): <?xml version="1.0" encoding="utf-8"?> <LinearL... Edit src/com/android/cptest/Dummy.java : package com.android.cptest; import java.io.... Add content provider ( src/com/android/cptest/XmlResource.java ): package com.android.cptest; import java.io.... Update AndroidManifest.xml : <?xml version="1.0" encoding="utf-8"?> <manifes... Add this section to the end of build.xml : <target name="-package-resources"> <ech... Build and install: ant install Screenshot: Remove the Dummy activity ( AndroidManifest.xml ): <?xml version="1.0" encoding="utf-8"?> <manifes... Create a new project for...
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 Dr. Xi on January 14, 2010 00:28:27
Last update: March 30, 2011 15:37:44
A task that a Java developer does so frequently is to find out where a certain class can be found - to resolve compilation errors, classpath issues, or version conflicts of the same class introduced by multiple class loaders. A long while back I wrote a simple Perl script to perform the task. Later I was informed that there are Swing based Jar Browser and Jars Browser . Then, there are a couple of shell one-liners:
# one liner 1 find -name "*.jar" -print0 | xarg... But all of them share the same problem: if a class is in a jar nested in another jar, it cannot be found. Such is the case for a class inside a jar under the WEB-INF/lib directory of a...
Created by nogeek on December 31, 2010 11:56:25
Last update: December 31, 2010 11:56:25
These are the steps to create a JBoss 5.1.0 configuration with Tomcat from the built-in minimal configuration. Change directory to $JBOSS_HOME/server . Make a copy of the minimal configuration.
cp -R minimal tomcatonly Copy bindingservice.beans from the default configuration. cp -R default/conf/bindingservice.beans tomcatonly... Copy login-config.xml from the default configuration. cp default/conf/login-config.xml tomcatonly/conf/ Edit tomcatonly/conf/jboss-service.xml : Add jars from the common/lib directory: <!-- Load all jars from the JBOSS_DIST/serv... Add the JAAS security manager section (copy from the default profile, and yes, JBoss tomcat can't live without the JBoss JAAS manager). <!-- JAAS security manager and realm mappin... Copy the Tomcat (JBoss web) deployer from the default configuration. cp -R default/deployers/jbossweb.deployer tomcaton... Copy metadata-deployer-jboss-beans.xml and security-deployer-jboss-beans.xml from the default profile. cp default/deployers/metadata-deployer-jboss-b... Copy...
Created by Dr. Xi on July 19, 2010 21:58:34
Last update: July 23, 2010 21:37:23
Parsing XML in Java is really simple:
import java.io.*; import javax.xml.parsers.Docu... The parser implementation details are hidden behind the JAXP API. In case you want to know which parser implementation is used, this is what the JavaDoc for DocumentBuilderFactory.newInstance says: Use the javax.xml.parsers.DocumentBuilderFactory system property. Use the properties file " lib/jaxp.properties " in the JRE directory. This configuration file is in standard java.util.Properties format and contains the fully qualified name of the implementation class with the key being the system property defined above. The jaxp.properties file is read only once by the JAXP implementation and it's values are then cached for future use. If the file does not exist when the first attempt is made to read from it, no further attempts are made to...
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...
