To read resources from the jar file where the class itself is present, you can use following way, for example for reading image icons from jar:
ImageIcon icon =new ImageIcon(this.getClass().getResource("icons/" + name));
getResource() gives you url resource of the image, you can use getResourceAsStream to get stream as well.
for example:
http://forum.java.sun.com/thread.jspa?threadID=633261&messageID=3669756