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Created by freyo on February 06, 2013 21:10:47    Last update: February 06, 2013 21:12:18
I have an old Samung phone to be used as a toy. After restoring back to factory image and power on, I was stuck at the activate service screen. Unfortunately, the four corner magic touch did not work. So I did quite a bit of digging and this is what worked on my Samsung Continuum: Press emergency call button, then at the dialer, press * # 8 3 7 8 6 6 3 3 , press the Home key From the home screen, tap phone icon, Dial * # 2 2 7 4 5 9 2 7 Enter SPC code: ______ displays tap in white box to show virtual keyboard, enter 6 digit code (default: 000000), tap OK Select “Hidden menu Enable”, tap OK From...
Created by Dr. Xi on November 11, 2011 10:05:22    Last update: November 11, 2011 10:12:01
This is an HTML image tag filter using Java regex. It takes a string, finds the img tags, replaces the src attribute with one provided by the filter, then adds a class name to the class attribute. import java.util.regex.*; import java.io.*; ... Test file: <div id="HTML snippet"> <img src="img/big/txt-m...
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 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 Dr. Xi on October 16, 2008 20:45:40    Last update: March 28, 2011 20:23:22
Java's built-in classes are way too complex/flexible for a simple protocol like HTTP. This is a wrapper to simplify HTTP GET and POST. import java.io.*; import java.net.*; imp... A simple test: import java.io.*; import java.util.*; ...
Created by Dr. Xi on July 21, 2010 22:14:53    Last update: July 21, 2010 22:14:53
This is a Java program to test XPATH expressions with namespace option. It's been tested with JDK1.6. import java.io.FileInputStream; import java.uti... Following Getting Started with XML Security , these are the test files: Without namespace (patient.xml). <PatientRecord> <Name>John Doe</Nam... With namespace (patient_ns.xml). <med:PatientRecord xmlns:med="http://www.medic... Test results: C:\>java XPathExample patient.xml /PatientRecord/V...
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 October 09, 2009 02:56:44    Last update: October 09, 2009 02:56:44
The Luhn algorithm is used to validate credit card numbers. This class provides two methods: one to validate that a number passes the Luhn algorithm validation, the other to generate a check digit that makes a number pass the Luhn validation. public class Luhn { public static void main...