Zip file creation and problems unzipping

[Donna Reschke]

I am using the java.util.zip.ZipOutputStream to create a zip file. I store it on a server and then invoke a script file that ftp's this zip file to our mainframe environment where a COBOL program tries to unzip it with PKUnzip. Each time they try to unzip my zip file they get an "invalid zip archive" error. But I am able to unzip it with WinZip. Does anyone have any experience with this or know of anything I can do differently? I've put a code snippet of how I zip the text file below.
Thanks, Donna

    
String fileToZip = "myTestFile.txt";
ZipOutputStream zout = new ZipOutputStream(new FileOutputStream("myTest.zip"));
 
zout.setLevel(Deflater.DEFAULT_COMPRESSION);
zout.putNextEntry(new ZipEntry(fileToZip));
 
String validBaleCt = formatBaleCt.format(iValidBaleCt);
 
sOutRec = "A";
sOutRec += validBaleCt;
sOutRec += buyId;
sOutRec += pyofDt;
sOutRec += sentDt;
sOutRec += filler1;
sOutRec += testFlag;
sOutRec += filler2;
sOutRec += newLine;
 
zout.write(sOutRec.getBytes(), 0, sOutRec.length());
 
for (int i = 0; i < iValidBaleCt; i++) {
 
bale = (CCRInvoiceRequestDataModel) bales.get(i);
ginCd = bale.getGinCd();
ginTag = bale.getGinTag();
whseCd = bale.getWhseCd();
rcptNbr = bale.getRcptNbr();
eadId = bale.getEadId();
eadInd = bale.getEadInd();
txnCd = bale.getBaleTxnCd();
 
Integer iGinCd = new Integer(ginCd);
ginCd = formatGinCode.format(iGinCd);
 
Integer iGinTag = new Integer(ginTag);
ginTag = formatGinTag.format(iGinTag);
 
Integer iWhseCd = new Integer(whseCd);
whseCd = formatWhseCode.format(iWhseCd);
 
Integer iRcptNbr = new Integer(rcptNbr);
rcptNbr = formatWhseRcpt.format(iRcptNbr);
 
sOutRec = "B";
sOutRec += filler3;
sOutRec += buyerInfo;
sOutRec += filler4;
sOutRec += ginCd;
sOutRec += ginTag;
sOutRec += cropYr;
sOutRec += whseCd;
sOutRec += rcptNbr;
sOutRec += eadId;
sOutRec += eadInd;
sOutRec += txnCd;
sOutRec += filler5;
sOutRec += newLine;
 
zout.write(sOutRec.getBytes(), 0, sOutRec.length());
}
 
zout.closeEntry();
zout.close(); 

[Ulf Dittmer]

Are you certain that PKUnzip can handle Deflater.DEFAULT_COMPRESSION?

Here is a canonical example of how to create ZIP files.

[Donna Reschke]

Well I ended up commenting out the "setLevel" instruction which I'm not sure if that was causing part of the problem or not. The real issue was that I wasn't specifying "binary" when I ftp'd the file to the mainframe. ONce I did that, the COBOL program was able to unzip the file.
Thanks!
Donna