Name: js151677			Date: 07/28/2004


FULL PRODUCT VERSION :
java version "1.4.2_04"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.2_04-b05)
Java HotSpot(TM) Client VM (build 1.4.2_04-b05, mixed mode)


ADDITIONAL OS VERSION INFORMATION :
Linux baltic 2.6.7-1-686-smp #1 SMP Thu Jul 8 06:08:37 EDT 2004 i686 GNU/Linux


A DESCRIPTION OF THE PROBLEM :
JarDiff reuses ZipEntry objects without properly clearing out their compressed size:

[From JarDiff.java]:

	    while (entries.hasNext()) {
		String newName = (String)entries.next();
		if (_debug) {
		    System.out.println("New File: " + newName);
		}
		writeEntry(jos, newJar.getEntryByName(newName), newJar);
	    }

later in writeEntry() we see it directly added to the new jar file:

    private static void writeEntry(JarOutputStream jos, JarEntry entry,
                            InputStream data) throws IOException {
        jos.putNextEntry(entry);

If the data compresses to a different size in the new jar file, the ZipOutputStream will fail with an exception: invalid entry compressed size.

The compressed size should be cleared out before reusing the ZipEntry.


STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Attempt to create a jardiff of jar files created with a non-standard compression level.


REPRODUCIBILITY :
This bug can be reproduced always.

CUSTOMER SUBMITTED WORKAROUND :
Before creating a jardiff the two source jar files can be recreated completely with the same JVM version that will be used to perform the jardiff.
(Incident Review ID: 290083) 
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