Extract File From Zip Archive

[Isaac Hewitt]

This question is addressed to anyone with experience in Zip files.

I have had no problem unzipping the entire contents of a zip archive.

I have another method to extract only one file, but when I try to open the extracted file, I find that each time the extracted file has 0 bytes in it, so I don't think it has been extracted. I tried so many things and searched high and low on the Internet but to no avail.

The idea is to allow the user to open a file in the archive to see its contents.

So I want it extracted to a temporary location and then from their calling Runtime.exec().

  private final String getZipFileEntry(String file) {
    final String dest = "./user/temp/preview/";
    String path = this.zipFile.getAbsolutePath(); //zip file name with path
    final int BUFFER = 2048;
    java.io.File f = null;
 
    try {
     ZipFile zipFile = new ZipFile(path);
        
     ZipInputStream in = new ZipInputStream(new FileInputStream(path));
 for(Enumeration<? extends ZipEntry> zen = zipFile.entries();zen.hasMoreElements() :wink:  {
      if(zen.nextElement().isDirectory()) continue;
        path = zen.nextElement().getName();
        if(path.equals(ZipUtilities.getFileIndepth(file))) {
         f = new java.io.File(dest, path); 
          FileOutputStream fout = new FileOutputStream(f);
          BufferedOutputStream bout = new BufferedOutputStream(fout, BUFFER);
           
        byte[] buf = new byte[1024];
        int len;
        while((len = in.read(buf)) > 0) bout.write(buf, 0, len);
        
        zipFile.close();
        fout.close();
        bout.flush();
        bout.close();
        in.close();
        break;
       }
     }
   } catch(Exception e) {
      Sytem.out.print("Freak out!!!);
   }
   return f.getAbsolutePath();
  }

the returned String is used in conjuction with another method called from actionPerformed() in a MenuItem.

//inside actionPerformed()
   final String f = tree.getLastSelectedPathComponent().toString();
   ZipUtilities.openFileWithAssociatedProgram(this.getZipFileEntry(f));

[rohit leeta]

This example may help:

http://www.java-tips.org/blog/java-se/how-to-modify-a-jar-file.html