Viewing contents of zip file

[Java Tip]

The presented example shows how to view the contents of a zip file.

class ViewZip {
  public static void main(String args[]) throws IOException {
   InputStream in = new BufferedInputStream(new FileInputStream(args[0]));
   ZipInputStream zin = new ZipInputStream(in);
   ZipEntry e;
   System.err.println("Size\t  Date       Time    Method    Ratio   Name");
   System.err.println("----\t  ----       ----    ------    -----   ----");
   while((e=zin.getNextEntry())!= null) {
     zin.closeEntry();
     print(e);
   }
   zin.close();
  }
    
  public static void print(ZipEntry e) {
   PrintStream err = System.err;
   err.print(e.getSize() + "\t");
    
   DateFormat df = new SimpleDateFormat ("yyyy.mm.dd  hh:mm:ss");
   Date d = new Date(e.getTime());
    
   err.print(df.format(d) + " ");
   if (e.getMethod() == ZipEntry.DEFLATED) {
     err.print("deflated  ");
     long size = e.getSize();
     if (size > 0) {
       long csize = e.getCompressedSize();
       long ratio = ((size-csize)*100) / size;
       if (ratio < 10) {
         err.write(' ');
       }
       err.print(ratio + "%   ");
     }
     else {
       err.print(" 0%    ");
     }
    }
    else {
      err.println(" (stored   0 %");
    }

    err.println(e.getName());
   }
}