I am working through some code I had written several years ago and am
sure that it worked then... I figured out my problem comes down to some
interaction with GZIPOutputStream and MemoryCacheImageOutputStream.  A
sample of code to show the problem is below...

If I comment out the MemoryCacheImageOutputStream and put in the
DataOutputStream it will work.

If I leave the MemoryCacheImageOutputStream and comment out the
GZIPOutputStream wrapper it will work.

Why does it not work with the MemoryCacheImageOutputStream and
GZIPOutputStream??

If I write out more data I watch a file in /tmp grow but when the
program finishes the file frank.txt.gz is still only 10 bytes (an empty
gzip?).

Any help would be appreciated!

import java.util.*;
import java.io.*;
import java.nio.*;
import java.util.zip.*;
import javax.imageio.stream.*;

public class Bob
{
   public static void main(String[] args)
   {
       OutputStream fos = null;
       String filename = "frank.txt.gz";

       try {
               fos = new FileOutputStream(new File(filename));
               if( filename.endsWith(".gz") )
                           { fos = new GZIPOutputStream( fos ); }
               fos = new BufferedOutputStream( fos );
       } catch (IOException e) {  System.out.println(e);
System.exit(0); }

       ImageOutputStream fcos = new MemoryCacheImageOutputStream(fos);
//      ImageOutputStream fcos = null; try { fcos = new
FileCacheImageOutputStream(fos, null);
} catch (Exception e) {}
//      DataOutputStream fcos = new DataOutputStream(fos);

       try {
           fcos.writeBytes("Here I am\n");
           fcos.close();
       }
       catch( Exception e)
       {
           System.out.println("could not write " + e);
System.exit(-1);
       }

   }

   public Bob()
       {
       }
}