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