Java/Development Class/Class Path

getClass().getResourceAsStream

   <source lang="java">
// This example is from the book _Java AWT Reference_ by John Zukowski.

// Written by John Zukowski. Copyright (c) 1997 O"Reilly & Associates. // You may study, use, modify, and distribute this example for any purpose. // This example is provided WITHOUT WARRANTY either expressed or import java.applet.Applet; import java.awt.Font; import java.awt.Graphics; import java.awt.Image; import java.io.IOException; import java.io.InputStream; import java.net.URL; import java.util.Properties; public class Prop11 extends Applet {

 Image im;
 Font f;
 String msg;
 public void paint(Graphics g) {
   g.setFont(f);
   if (im != null)
     g.drawImage(im, 50, 100, this);
   if (msg != null)
     g.drawString(msg, 50, 50);
 }
 public void init() {
   InputStream is = getClass().getResourceAsStream("prop11.list");
   Properties p = new Properties();
   try {
     p.load(is);
     f = Font.decode(p.getProperty("MyProg.font"));
     msg = p.getProperty("MyProg.message");
     String name = p.getProperty("MyProg.image");
     URL url = getClass().getResource(name);
     im = getImage(url);
   } catch (IOException e) {
     System.out.println("error loading props...");
   }
 }

} File: prop11.list MyProg.font.size=20 MyProg.font.type=italic-bold MyProg.font.name=Helvetica MyProg.message=Hello World

</source>
   
  
 
  

Load resource file: absolute from the classpath

   <source lang="java">

import java.io.IOException; import java.net.URL; public class Main {

 public static void main(String[] args) throws IOException {
   // absolute from the classpath
   URL url = Main.class.getResource("/mypackage/foo.txt");
 }

}

</source>
   
  
 
  

Load resource file: relative to the class location

   <source lang="java">

import java.io.IOException; import java.net.URL; public class Main {

 public static void main(String[] args) throws IOException {
   // relative to the class location
   URL url = Main.class.getResource("foo.txt");
 }

}

</source>
   
  
 
  

relative document loading in classpath

   <source lang="java">

import java.io.IOException; import java.net.URL; public class Main {

 public static void main(String[] args) throws IOException {
   // relative document
   URL url = Main.class.getResource("docs/bar.txt");
 }

}

</source>
   
  
 
  

Try adding one or more item(s) to class path

   <source lang="java">

/*

* Copyright (c) Ian F. Darwin, http://www.darwinsys.ru/, 1996-2002.
* All rights reserved. Software written by Ian F. Darwin and others.
* $Id: LICENSE,v 1.8 2004/02/09 03:33:38 ian Exp $
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
*    notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
*    notice, this list of conditions and the following disclaimer in the
*    documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS""
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
* 
* Java, the Duke mascot, and all variants of Sun"s Java "steaming coffee
* cup" logo are trademarks of Sun Microsystems. Sun"s, and James Gosling"s,
* pioneering role in inventing and promulgating (and standardizing) the Java 
* language and environment is gratefully acknowledged.
* 
* The pioneering role of Dennis Ritchie and Bjarne Stroustrup, of AT&T, for
* inventing predecessor languages C and C++ is also gratefully acknowledged.
*/

import java.util.Properties; /**

* Try adding one or more item(s) to class path.
*/

public class SysPropSet {

 static Properties p = System.getProperties();
 public static void main(String[] argv) {
   System.out.println("System Properties:");
   System.out.println("java.class.path now = " + getClassPath());
   p.setProperty("java.class.path", getClassPath() + ";"
       + "C:/jdk1.2/lib/tools.jar");
   System.out.println("java.class.path now = " + getClassPath());
   try {
     Class.forName("sun.tools.javap.JavaP");
   } catch (Exception e) {
     System.err.println(e);
     return;
   }
   System.out.println("Got it!!");
 }
 static String getClassPath() {
   return p.getProperty("java.class.path", null);
 }

}

      </source>