| /* |
| * 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.tools.zip; |
| |
| /** |
| * Parser/encoder for the "general purpose bit" field in ZIP's local |
| * file and central directory headers. |
| * |
| * @since Ant 1.9.0 |
| */ |
| public final class GeneralPurposeBit implements Cloneable { |
| /** |
| * Indicates that the file is encrypted. |
| */ |
| private static final int ENCRYPTION_FLAG = 1; |
| |
| /** |
| * Indicates that a data descriptor stored after the file contents |
| * will hold CRC and size information. |
| */ |
| private static final int DATA_DESCRIPTOR_FLAG = 1 << 3; |
| |
| /** |
| * Indicates strong encryption. |
| */ |
| private static final int STRONG_ENCRYPTION_FLAG = 1 << 6; |
| |
| /** |
| * Indicates that filenames are written in utf-8. |
| * |
| * <p>The only reason this is public is that {@link |
| * ZipOutputStream#EFS_FLAG} was public in several versions of |
| * Apache Ant and we needed a substitute for it.</p> |
| */ |
| public static final int UFT8_NAMES_FLAG = 1 << 11; |
| |
| private boolean languageEncodingFlag = false; |
| private boolean dataDescriptorFlag = false; |
| private boolean encryptionFlag = false; |
| private boolean strongEncryptionFlag = false; |
| |
| public GeneralPurposeBit() { |
| } |
| |
| /** |
| * whether the current entry uses UTF8 for file name and comment. |
| * |
| * @return boolean |
| */ |
| public boolean usesUTF8ForNames() { |
| return languageEncodingFlag; |
| } |
| |
| /** |
| * whether the current entry will use UTF8 for file name and comment. |
| * |
| * @param b boolean |
| */ |
| public void useUTF8ForNames(boolean b) { |
| languageEncodingFlag = b; |
| } |
| |
| /** |
| * whether the current entry uses the data descriptor to store CRC |
| * and size information |
| * |
| * @return boolean |
| */ |
| public boolean usesDataDescriptor() { |
| return dataDescriptorFlag; |
| } |
| |
| /** |
| * whether the current entry will use the data descriptor to store |
| * CRC and size information |
| * |
| * @param b boolean |
| */ |
| public void useDataDescriptor(boolean b) { |
| dataDescriptorFlag = b; |
| } |
| |
| /** |
| * whether the current entry is encrypted |
| * |
| * @return boolean |
| */ |
| public boolean usesEncryption() { |
| return encryptionFlag; |
| } |
| |
| /** |
| * whether the current entry will be encrypted |
| * |
| * @param b boolean |
| */ |
| public void useEncryption(boolean b) { |
| encryptionFlag = b; |
| } |
| |
| /** |
| * whether the current entry is encrypted using strong encryption |
| * |
| * @return boolean |
| */ |
| public boolean usesStrongEncryption() { |
| return encryptionFlag && strongEncryptionFlag; |
| } |
| |
| /** |
| * whether the current entry will be encrypted using strong encryption |
| * |
| * @param b boolean |
| */ |
| public void useStrongEncryption(boolean b) { |
| strongEncryptionFlag = b; |
| if (b) { |
| useEncryption(true); |
| } |
| } |
| |
| /** |
| * Encodes the set bits in a form suitable for ZIP archives. |
| * |
| * @return byte[] |
| */ |
| public byte[] encode() { |
| byte[] result = new byte[2]; |
| encode(result, 0); |
| return result; |
| } |
| |
| /** |
| * Encodes the set bits in a form suitable for ZIP archives. |
| * |
| * @param buf the output buffer |
| * @param offset |
| * The offset within the output buffer of the first byte to be written. |
| * must be non-negative and no larger than <tt>buf.length-2</tt> |
| */ |
| public void encode(byte[] buf, int offset) { |
| ZipShort.putShort((dataDescriptorFlag ? DATA_DESCRIPTOR_FLAG : 0) |
| | (languageEncodingFlag ? UFT8_NAMES_FLAG : 0) |
| | (encryptionFlag ? ENCRYPTION_FLAG : 0) |
| | (strongEncryptionFlag ? STRONG_ENCRYPTION_FLAG : 0), |
| buf, offset); |
| } |
| |
| /** |
| * Parses the supported flags from the given archive data. |
| * |
| * @param data local file header or a central directory entry. |
| * @param offset offset at which the general purpose bit starts |
| * @return GeneralPurposeBit |
| */ |
| public static GeneralPurposeBit parse(final byte[] data, final int offset) { |
| final int generalPurposeFlag = ZipShort.getValue(data, offset); |
| GeneralPurposeBit b = new GeneralPurposeBit(); |
| b.useDataDescriptor((generalPurposeFlag & DATA_DESCRIPTOR_FLAG) != 0); |
| b.useUTF8ForNames((generalPurposeFlag & UFT8_NAMES_FLAG) != 0); |
| b.useStrongEncryption((generalPurposeFlag & STRONG_ENCRYPTION_FLAG) |
| != 0); |
| b.useEncryption((generalPurposeFlag & ENCRYPTION_FLAG) != 0); |
| return b; |
| } |
| |
| @Override |
| public int hashCode() { |
| return 3 * (7 * (13 * (17 * (encryptionFlag ? 1 : 0) |
| + (strongEncryptionFlag ? 1 : 0)) |
| + (languageEncodingFlag ? 1 : 0)) |
| + (dataDescriptorFlag ? 1 : 0)); |
| } |
| |
| @Override |
| public boolean equals(Object o) { |
| if (!(o instanceof GeneralPurposeBit)) { |
| return false; |
| } |
| GeneralPurposeBit g = (GeneralPurposeBit) o; |
| return g.encryptionFlag == encryptionFlag |
| && g.strongEncryptionFlag == strongEncryptionFlag |
| && g.languageEncodingFlag == languageEncodingFlag |
| && g.dataDescriptorFlag == dataDescriptorFlag; |
| } |
| |
| @Override |
| public Object clone() { |
| try { |
| return super.clone(); |
| } catch (CloneNotSupportedException ex) { |
| // impossible |
| throw new RuntimeException("GeneralPurposeBit is not Cloneable?", ex); //NOSONAR |
| } |
| } |
| } |