Name: gm110360 Date: 05/31/2002


FULL PRODUCT VERSION :
java version "1.4.0"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.0-b92)
Java HotSpot(TM) Client VM (build 1.4.0-b92, mixed mode)


FULL OPERATING SYSTEM VERSION :

Windows NT 4.0

A DESCRIPTION OF THE PROBLEM :
The XMLDecoder appears to ignore the argument of
a constuctor which is itself the argument of a
constructor.


STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
1. javac XMLReader
2. java XMLReader Test.xml
3.

EXPECTED VERSUS ACTUAL BEHAVIOR :
The layout manager of the panel that is loaded
from the archive is a FlowLayout - it should be
a SpringLayout. You can see the layout manager
property as part of what is printed to the console
as the description of the panel.

ERROR MESSAGES/STACK TRACES THAT OCCUR :
There are no error messages but the resulting graph is not correct.
The decoder has called the no argument constructor to the JPanel -
leaving its layout manager as the default - a FlowLayout.

This bug can be reproduced always.

---------- BEGIN SOURCE ----------
Test.xml
--------

<?xml version="1.0" encoding="UTF-8"?>
<java version="1.4.0" class="java.beans.XMLDecoder">
 <object id="JPanel0" class="javax.swing.JPanel">
  <object class="javax.swing.SpringLayout">
   <void id="SpringLayout$SpringProxy0" method="getConstraint">
    <string>East</string>
    <object idref="JPanel0"/>
   </void>
  </object>
 </object>
</java>


XMLReader.java
--------------

import java.beans.XMLDecoder;
import java.io.BufferedInputStream;
import java.io.FileInputStream;

public class XMLReader {

    /**
     * Reads the named archive and returns the root object.
     *
     * @param filename A valid archive that was created with the LTP
     * @return the decoded object graph or null if an error occured.
     */
    public static void main(String[] args) throws Exception {
        if (args.length == 0) {
            System.out.println("Usage: XMLReader <filename>");
            return;
        }
        XMLDecoder d = new XMLDecoder(
                new BufferedInputStream(
                        new FileInputStream(args[0])));
        Object root = d.readObject();
        System.out.println(root);
        d.close();
    }

}

---------- END SOURCE ----------

CUSTOMER WORKAROUND :
Set the layout manager as a property on the
panel rather than passing it in as a constructor
argument.
(Review ID: 145689)
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