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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 Dr. Xi on September 30, 2011 15:34:47
Last update: September 30, 2011 15:34:47
A naive try would be something like this:
$ nc -l 8082 | nc remote_host 80 Yes, it does forward the request from local port 8082 to remote_host:80 , but the response is dumped to stdout , not routed back to the client as expected. Using a named pipe makes it work: $ mkfifo backpipe $ nc -l 8082 0<backpipe | nc ... Use tee to get a glimpse of the response through the pipe (I wasn't able to find a way to dump the request): $ nc -k -l 8082 0<backpipe | nc localhost 80 | tee... The GNU netcat has a different syntax than the stock nc . It also supports different switches. To listen to port 1234: $ netcat -l -p 1234...
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 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 May 26, 2011 21:16:22
Last update: June 02, 2011 14:39:57
Given a class A :
class A {
public int doWork(String s, int i...
it is OK to call method doWork with both primitive types and the corresponding wrapping object types:
new A().doWork("Hello", 1, false);
new A().doWo...
However, if you find method by parameter types with Java reflection, the types must match exactly, i.e.,
Class<?> c = Class.forName("A");
// This call f...
This is a utility to find methods with compatible parameter types:
import java.lang.reflect.*;
import java.util.*;...
Example usage:
Method m = ReflectionUtil.getCompatibleMethod(c, "...
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 March 30, 2011 13:43:05
Last update: March 30, 2011 13:45:27
Method 1 - use javap with verbose flag:
$ javap HelloWorld -verbose | head
Compiled fro...
Method 2 - use a utility class:
import java.io.*;
import java.nio.ByteBuffer;
...
According to the VM Spec , a Java class file has this structure:
ClassFile {
u4 magic;
...
Created by James on March 13, 2011 13:44:37
Last update: March 21, 2011 11:30:55
This is a jQuery input control that lets you enter any number of input rows of name and value pairs.
<!DOCTYPE html>
<html>
<head>
<title>jQu...
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 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...
