[Jazzlib-developers] Problem copying zip entry from one zip file to another

[Jim M. <jim...@co...>]

I am trying to create a new zip file containing selected entries from
another zip file.  I am using jazzlib-0.07 with Sun's JDK 1.5.0_04 on Redhat
Fedora Core 4 Linux.

I create an entry in the new file with the same name as the one in the old
file, then call the following method. 

----------------------------
    private void copyEntryData(ZipFile inputZipFile,
            ZipOutputStream zipOutputStream, ZipEntry entry) {
        try {
            int data = 0;
            InputStream inputStream = inputZipFile.getInputStream(entry);
            while ((data = inputStream.read()) >= 0) {
                zipOutputStream.write(data);
            }
            zipOutputStream.flush();
            zipOutputStream.closeEntry();
            inputStream.close();
        } catch (IOException e) {
            final String message = "Unable to read or write file";
            recordException(message, e);
        }
    }
----------------------------

This runs without throwing an exception.  Later, though, when I call
zipOutputStream.close(), I get:

----------------------------
Error when trying to close zip output stream:
/home/jmcmaster/nile/assets/dex/EXT065_TEXT/eps.zip
net.sf.jazzlib.ZipException: compressed size was 195651, but I expected
464058
        at
net.sf.jazzlib.ZipOutputStream.closeEntry(ZipOutputStream.java:276)
        at
net.sf.jazzlib.ZipOutputStream.finish(ZipOutputStream.java:336)
        at
net.sf.jazzlib.DeflaterOutputStream.close(DeflaterOutputStream.java:171)
----------------------------

(NOTE:  The actual expected size is 196653.  The 464058 is the uncompressed
size.  Jazzlib has a bug that sticks the wrong size in the exception
message.)

Trying to unzip the file yields:

----------------------------
Archive:  eps.zip
  End-of-central-directory signature not found.  Either this file is not
  a zipfile, or it constitutes one disk of a multi-part archive.  In the
  latter case the central directory and zipfile comment will be found on
  the last disk(s) of this archive.
unzip:  cannot find zipfile directory in one of eps.zip or
        eps.zip.zip, and cannot find eps.zip.ZIP, period.
----------------------------

I am processing two kinds of entries:  xml files a few hundred bytes in
length, and EPS files several hundred thousand bytes in length.  This never
happens with the former, but consistently happens with the latter.  I do get
the same results with java's zip classes.  A co-worker who experienced the
same problem worked around it by extracting the entry to a temporary disk
file, then writing from there to the output zip file.  I would rather not if
I can avoid that.  I read a java forum posting where someone solved a
similar problem by switching to TrueZip, but I would rather not do that
either.

Is there a way to fix this?  I suspect something wrong in the deflater, but
have no clue how to debug it.

Thank you.

-- 
Jim McMaster
mailto:jim...@co...