https://commons.apache.org/proper/commons-compress/: Apache Commons Compress software defines an API for working with compression and archive formats. These include: bzip2, gzip, pack200, lzma, xz, Snappy, traditional Unix Compress, DEFLATE, DEFLATE64, LZ4, Brotli, Zstandard and ar, cpio, jar, tar, zip, dump, 7z, arj. (The Apache Software Foundation)
  • Wolfgang Glas
  • Christian Kohlschütte
  • Bear Giles
  • Michael Kuss
  • Lasse Collin
  • John Kodis
  • BELUGA BEHR
  • Simon Spero
  • Michael Hausegger
  • Torsten Curdt
  • Stefan Bodewig
  • Sebastian Bazley
  • Christian Grobmeier
  • Julius Davies
  • Damjan Jovanovic
  • Emmanuel Bourg
  • Gary Gregory
  • Rob Tompkins 
/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
package org.apache.commons.compress.archivers.zip;

import java.util.zip.ZipException;


General format of extra field data.

Extra fields usually appear twice per file, once in the local file data and once in the central directory. Usually they are the same, but they don't have to be. java.util.zip.ZipOutputStream will only use the local file data in both places.


/**
 * General format of extra field data.
 *
 * <p>Extra fields usually appear twice per file, once in the local
 * file data and once in the central directory.  Usually they are the
 * same, but they don't have to be.  {@link
 * java.util.zip.ZipOutputStream java.util.zip.ZipOutputStream} will
 * only use the local file data in both places.</p>
 *
 */
public interface ZipExtraField {
    
Size of an extra field field header (id + length).

Since:1.14
/**
     * Size of an extra field field header (id + length).
     * @since 1.14
     */
    int EXTRAFIELD_HEADER_SIZE = 4;

    
The Header-ID.

Returns:The HeaderId value
/**
     * The Header-ID.
     *
     * @return The HeaderId value
     */
    ZipShort getHeaderId();

    
Length of the extra field in the local file data - without
Header-ID or length specifier.

Returns:the length of the field in the local file data
/**
     * Length of the extra field in the local file data - without
     * Header-ID or length specifier.
     * @return the length of the field in the local file data
     */
    ZipShort getLocalFileDataLength();

    
Length of the extra field in the central directory - without
Header-ID or length specifier.

Returns:the length of the field in the central directory
/**
     * Length of the extra field in the central directory - without
     * Header-ID or length specifier.
     * @return the length of the field in the central directory
     */
    ZipShort getCentralDirectoryLength();

    
The actual data to put into local file data - without Header-ID
or length specifier.

Returns:the data
/**
     * The actual data to put into local file data - without Header-ID
     * or length specifier.
     * @return the data
     */
    byte[] getLocalFileDataData();

    
The actual data to put into central directory - without Header-ID or
length specifier.

Returns:the data
/**
     * The actual data to put into central directory - without Header-ID or
     * length specifier.
     * @return the data
     */
    byte[] getCentralDirectoryData();

    
Populate data from this array as if it was in local file data.

Params:
  • buffer – the buffer to read data from
  • offset – offset into buffer to read data
  • length – the length of data
Throws:
/**
     * Populate data from this array as if it was in local file data.
     *
     * @param buffer the buffer to read data from
     * @param offset offset into buffer to read data
     * @param length the length of data
     * @throws ZipException on error
     */
    void parseFromLocalFileData(byte[] buffer, int offset, int length)
        throws ZipException;

    
Populate data from this array as if it was in central directory data.

Params:
  • buffer – the buffer to read data from
  • offset – offset into buffer to read data
  • length – the length of data
Throws:
/**
     * Populate data from this array as if it was in central directory data.
     *
     * @param buffer the buffer to read data from
     * @param offset offset into buffer to read data
     * @param length the length of data
     * @throws ZipException on error
     */
    void parseFromCentralDirectoryData(byte[] buffer, int offset, int length)
        throws ZipException;
}