code: public static boolean replaceEntry(final File zip, final ZipEntrySource entry) {
      return operateInPlace(zip, new InPlaceAction() {
        public boolean act(File tmpFile) {
          return replaceEntry(zip, entry, tmpFile);
        }
      });
    }
docs: Changes an existing ZIP file: replaces a given entry in it.
  
  @param zip
  an existing ZIP file.
  @param entry
  new ZIP entry.
  @return <code>true</code> if the entry was replaced.