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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 Fang on March 06, 2012 12:24:53    Last update: March 06, 2012 12:24:53
Validation groups can be used to control which rules validation rules to run. A validation group can be identified by any Java interface (not class!). Multiple validation groups may be specified when validating. In this example, I added a validation group named MyValidationGroup ( src/main/java/com/example/MyValidationGroup.java in Maven project): package com.example; public interface MyVal... and added a @Size rule for a person's name, because my database can only store up to 15 characters for a person's name: package com.example; import javax.validatio... Now validate Person with a JUnit test ( src/test/java/com/example/TestPersonWithGroup.java in Maven project): package com.example; import java.util.Set; ... Test with " mvn clean test ". The rules where groups is not specified, which belong to the javax.validation.groups.Default group, are not executed with these tests.
Created by freyo on May 13, 2011 15:45:29    Last update: September 20, 2011 08:08:12
This is an Android app that dumps any binarized xml file as plain text - to the sdcard on the device or emulator. build.xml : <?xml version="1.0" encoding="UTF-8"?> <project... AndroidManifest.xml <?xml version="1.0" encoding="utf-8"?> <man... res/layout/main.xml <?xml version="1.0" encoding="utf-8"?> <Lin... res/values/strings.xml : <?xml version="1.0" encoding="utf-8"?> <res... src/com/android/xmltool/DumpXml.java package com.android.xmltool; import java.ut... Screenshot Pre-built APK can be downloaded from: http://code.google.com/p/android-binxml-dump/
Created by alfa on July 15, 2011 13:25:45    Last update: July 15, 2011 13:25:45
Read the whole contents of a file into a String. It's better to read the whole file as bytes and convert to String than to read the file line by line and concatenate the lines. String getFileContents(String fileName) throws... Using java.nio : import java.io.FileInputStream; import java...
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 alfa on June 02, 2011 13:04:18    Last update: June 02, 2011 13:04:18
Some javap usage examples. Start from HelloWorld.java : @Deprecated public class HelloWorld { pu... javap -c HelloWorld outputs: Compiled from "HelloWorld.java" public class He... javap -v HelloWorld outputs ( -v for verbose mode): Compiled from "HelloWorld.java" public class He... The output consists of: " Compiled from... " header Class attributes. For the HelloWorld example, there are two: SourceFile and Deprecated . Minor and major class file version Constant pool Disassembled code LineNumberTable for debugging purposes. javap by default only prints package/protected/public members. To display all members including private, use the -p switch. javap -v -p HelloWorld
Created by meiu on March 31, 2011 19:54:05    Last update: March 31, 2011 19:54:05
With StringBuffer/StringBuilder: public class ReverseString { private static... Without StringBuffer/StringBuilder: public class ReverseString { private static...
Created by Dr. Xi on March 28, 2011 20:51:30    Last update: March 28, 2011 20:53:46
HTTP basic authentication is just Base64 encoded user name and password passed in as the Authorization header. So the following code works: // encode user name and password String credent... However, since JDK 1.2, there's a more Java friendly way: Authenticator.setDefault(new Authenticator() { ... Test code: import java.net.*; import java.io.*; pub...
Created by Dr. Xi on March 02, 2011 11:39:18    Last update: March 09, 2011 12:19:30
Some peculiarities about Java PrintWriter: PrintWriter never throws any exceptions. From JavaDoc : Methods in this class never throw I/O exceptions, although some of its constructors may. The client may inquire as to whether any errors have occurred by invoking checkError(). When error occurs, you'll never know anything more than that it occured, because checkError returns boolean. When a character is out of the range of the character encoding of the PrintWriter, it prints a question mark (?). But this is not an error. Test code: import java.io.*; public class TestPrintWri... Latin1 test result: java TestPrintWriter iso-8859-1 | od -bc 000000... UTF-8 test result: java TestPrintWriter utf-8 | od -bc 0000000 141... Also, the constructor throws a FileNotFoundException when you try to write to a...
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...
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