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JDK-6432010 : ZipException although zip file is OK (invalid CEN header bad compression method)

Details
Type:
Bug
Submit Date:
2006-05-31
Status:
Closed
Updated Date:
2011-02-16
Project Name:
JDK
Resolved Date:
2006-05-31
Component:
core-libs
OS:
solaris_8
Sub-Component:
java.util.jar
CPU:
sparc
Priority:
P4
Resolution:
Not an Issue
Affected Versions:
5.0
Fixed Versions:

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Description
FULL PRODUCT VERSION :
java version "1.5.0_06"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.5.0_06-b05)
Java HotSpot(TM) Client VM (build 1.5.0_06-b05, mixed mode, sharing)

ADDITIONAL OS VERSION INFORMATION :
SunOS braw061 5.8 Generic_117350-28 sun4u sparc SUNW,Sun-Blade-1500

A DESCRIPTION OF THE PROBLEM :
We have a file which needs to be unzip using java.util.zip.ZipFile.

It was created a class which would unzip it but when executing new ZipFile("myzip.zip) an exception is received :

Exception in thread "main" java.util.zip.ZipException: invalid CEN header (bad compression method)

If I try to decompress the same file using "unzip" or "winzip" no errors occour but when using "jar" it also fails giving the following message:


java.util.zip.ZipException: invalid CEN header (bad compression method)
        at java.util.zip.ZipFile.open(Native Method)
        at java.util.zip.ZipFile.<init>(ZipFile.java:203)
        at java.util.jar.JarFile.<init>(JarFile.java:132)
        at java.util.jar.JarFile.<init>(JarFile.java:70)
        at sun.tools.jar.Main.getJarPath(Main.java:793)
        at sun.tools.jar.Main.genIndex(Main.java:827)
        at sun.tools.jar.Main.run(Main.java:195)
        at sun.tools.jar.Main.main(Main.java:903)

It seems that this bug is connected to bug 4419591.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
1 - First you will need to have my specific zip file which I can send you by mail

2- Run the code I've provided here.


ERROR MESSAGES/STACK TRACES THAT OCCUR :
Exception in thread "main" java.util.zip.ZipException: invalid CEN header (bad compression method)

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.Enumeration;
import java.util.zip.ZipEntry;
import java.util.zip.ZipException;
import java.util.zip.ZipFile;


public class UnZip{
	
	public static ZipFile zf;
	public static final int EOF = -1;
	
	
	public static void main( String argv[] ) throws IOException {
		
		Enumeration e;
		
		try {
								
			zf = new ZipFile( "myzip.zip" );
			e = zf.entries();
			
			while( e.hasMoreElements() ) {
				
				ZipEntry target = (ZipEntry)e.nextElement();
				System.out.print( target.getName() + " ." );
				saveEntry( target );
				System.out.println( ". unpacked" );
			}
		}
		catch( FileNotFoundException exc ){
			System.out.println( "zipfile not found" );
		}
	}
	
	
	public static void saveEntry( ZipEntry target )
	throws ZipException,IOException {
		
		try {
			File file = new File( target.getName() );
			if( target.isDirectory() ) {
				file.mkdirs();
			}
			else {
				InputStream is = zf.getInputStream( target );
				BufferedInputStream bis = new BufferedInputStream( is );
				
				if ( file.getParent() != null){
					File dir;
					dir = new File( file.getParent() );
					dir.mkdirs();
				}
				FileOutputStream fos = new FileOutputStream( file );
				BufferedOutputStream bos = new BufferedOutputStream( fos );
				
				int c;
				while( ( c = bis.read() ) != EOF ) {
					bos.write( (byte)c );
				}
				bos.close();
				fos.close();
			}
		}
		catch( ZipException e ){
			throw e;
		}
		catch( IOException e ){
			throw e;
		}
	}
}
---------- END SOURCE ----------

                                    

Comments
EVALUATION

The given file "test.zip" has an entry named atqsh.1so, which use a compression method 6, "Imploding", which is not supported by our JDK.  We support only Stored (0) and Deflated (8).
                                     
2006-05-31



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