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Created by Dr. Xi on June 06, 2009 18:31:44    Last update: June 25, 2012 12:37:35
You can use the system call from the os module to execute an external program: >>> import os >>> os.system(the_command_line_st... However, the path to the executable contains a space character, the system call treats the strings after the first space as arguments, causing an error. Python doc recommends the use of the subprocess module: The subprocess module provides more powerful facilities for spawning new processes and retrieving their results; using that module is preferable to using this function. For example, using wget to get the google home page: >>> from subprocess import Popen, PIPE >>> (out... or >>> import subprocess >>>['cur...
Created by alfa on July 01, 2011 13:16:12    Last update: July 01, 2011 13:16:12
This is a simple doclet that prints all public methods and their parameter names and types. Code import com.sun.javadoc.*; public class List... Compile javac -cp $JAVA_HOME/lib/tools.jar:. ListMethodsDo... Use javadoc -doclet ListMethodsDoclet -sourcepath /pat...
Created by freyo on May 23, 2011 14:30:18    Last update: May 23, 2011 14:31:08
There are two distinct ways to process XPath: with namespace and without namespace. The code is different depending on whether the parser is namespace aware. Code without namespace: import*; import javax.xml.parsers.*; ... code with namespace: import*; import java.util.Iterator; ... XML without namespace: <?xml version="1.0" encoding="UTF-8" standalone="n... XML with namespace: <?xml version="1.0" encoding="UTF-8" standalone="n... The same XPath expression works for both XML files when the parser is not namespace aware. When the parser is namespace aware, you have to adjust the XPath accordingly depending on whether the XML has namespace declarations: " /test-license/licensee/name/text() " works for the XML file without namespace, while " /p:test-license/p:licensee/p:name/text() " works for the XML file with namespace.
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 June 19, 2010 04:34:01    Last update: June 19, 2010 04:39:13
Java SE 6 contains built-in utilities to generate XML signatures. This is an example that generates XML signatures using a Java keystore. It has options to generate signature for the whole document, for an element with a specific ID, or for elements matched by an XPATH expression. The XML document used to test is taken from Getting Started with XML Security : <?xml version="1.0"?> <PatientRecord> ... This is the Java code: import; import However, it looks like the XPATH transform is not working. The digest generated with XPATH filter is exactly the same as that without it (i.e., the whole document)! Another reference: Programming With the Java XML Digital Signature API
Created by Dr. Xi on September 25, 2008 02:58:27    Last update: October 14, 2008 22:49:32
This following code came from a JavaWorld tip, with some minor modifications. public class JWhich { /** * Retu...