001/* 002 * Licensed to the Apache Software Foundation (ASF) under one or more 003 * contributor license agreements. See the NOTICE file distributed with 004 * this work for additional information regarding copyright ownership. 005 * The ASF licenses this file to You under the Apache License, Version 2.0 006 * (the "License"); you may not use this file except in compliance with 007 * the License. You may obtain a copy of the License at 008 * 009 * http://www.apache.org/licenses/LICENSE-2.0 010 * 011 * Unless required by applicable law or agreed to in writing, software 012 * distributed under the License is distributed on an "AS IS" BASIS, 013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 014 * See the License for the specific language governing permissions and 015 * limitations under the License. 016 * 017 */ 018package org.apache.commons.compress.archivers.zip; 019 020import java.io.Serializable; 021 022import static org.apache.commons.compress.archivers.zip.ZipConstants.BYTE_MASK; 023import static org.apache.commons.compress.archivers.zip.ZipConstants.WORD; 024 025/** 026 * Utility class that represents a four byte integer with conversion 027 * rules for the big endian byte order of ZIP files. 028 * @Immutable 029 */ 030public final class ZipLong implements Cloneable, Serializable { 031 private static final long serialVersionUID = 1L; 032 033 //private static final int BYTE_BIT_SIZE = 8; 034 035 private static final int BYTE_1 = 1; 036 private static final int BYTE_1_MASK = 0xFF00; 037 private static final int BYTE_1_SHIFT = 8; 038 039 private static final int BYTE_2 = 2; 040 private static final int BYTE_2_MASK = 0xFF0000; 041 private static final int BYTE_2_SHIFT = 16; 042 043 private static final int BYTE_3 = 3; 044 private static final long BYTE_3_MASK = 0xFF000000L; 045 private static final int BYTE_3_SHIFT = 24; 046 047 private final long value; 048 049 /** Central File Header Signature */ 050 public static final ZipLong CFH_SIG = new ZipLong(0X02014B50L); 051 052 /** Local File Header Signature */ 053 public static final ZipLong LFH_SIG = new ZipLong(0X04034B50L); 054 055 /** 056 * Data Descriptor signature. 057 * 058 * <p>Actually, PKWARE uses this as marker for split/spanned 059 * archives and other archivers have started to use it as Data 060 * Descriptor signature (as well).</p> 061 * @since 1.1 062 */ 063 public static final ZipLong DD_SIG = new ZipLong(0X08074B50L); 064 065 /** 066 * Value stored in size and similar fields if ZIP64 extensions are 067 * used. 068 * @since 1.3 069 */ 070 static final ZipLong ZIP64_MAGIC = new ZipLong(ZipConstants.ZIP64_MAGIC); 071 072 /** 073 * Marks ZIP archives that were supposed to be split or spanned 074 * but only needed a single segment in then end (so are actually 075 * neither split nor spanned). 076 * 077 * <p>This is the "PK00" prefix found in some archives.</p> 078 * @since 1.5 079 */ 080 public static final ZipLong SINGLE_SEGMENT_SPLIT_MARKER = 081 new ZipLong(0X30304B50L); 082 083 /** 084 * Archive extra data record signature. 085 * @since 1.5 086 */ 087 public static final ZipLong AED_SIG = new ZipLong(0X08064B50L); 088 089 /** 090 * Create instance from a number. 091 * @param value the long to store as a ZipLong 092 */ 093 public ZipLong(final long value) { 094 this.value = value; 095 } 096 097 /** 098 * Create instance from bytes. 099 * @param bytes the bytes to store as a ZipLong 100 */ 101 public ZipLong (final byte[] bytes) { 102 this(bytes, 0); 103 } 104 105 /** 106 * Create instance from the four bytes starting at offset. 107 * @param bytes the bytes to store as a ZipLong 108 * @param offset the offset to start 109 */ 110 public ZipLong (final byte[] bytes, final int offset) { 111 value = ZipLong.getValue(bytes, offset); 112 } 113 114 /** 115 * Get value as four bytes in big endian byte order. 116 * @return value as four bytes in big endian order 117 */ 118 public byte[] getBytes() { 119 return ZipLong.getBytes(value); 120 } 121 122 /** 123 * Get value as Java long. 124 * @return value as a long 125 */ 126 public long getValue() { 127 return value; 128 } 129 130 /** 131 * Get value as four bytes in big endian byte order. 132 * @param value the value to convert 133 * @return value as four bytes in big endian byte order 134 */ 135 public static byte[] getBytes(final long value) { 136 final byte[] result = new byte[WORD]; 137 putLong(value, result, 0); 138 return result; 139 } 140 141 /** 142 * put the value as four bytes in big endian byte order. 143 * @param value the Java long to convert to bytes 144 * @param buf the output buffer 145 * @param offset 146 * The offset within the output buffer of the first byte to be written. 147 * must be non-negative and no larger than <tt>buf.length-4</tt> 148 */ 149 150 public static void putLong(final long value, final byte[] buf, int offset) { 151 buf[offset++] = (byte) ((value & BYTE_MASK)); 152 buf[offset++] = (byte) ((value & BYTE_1_MASK) >> BYTE_1_SHIFT); 153 buf[offset++] = (byte) ((value & BYTE_2_MASK) >> BYTE_2_SHIFT); 154 buf[offset] = (byte) ((value & BYTE_3_MASK) >> BYTE_3_SHIFT); 155 } 156 157 public void putLong(final byte[] buf, final int offset) { 158 putLong(value, buf, offset); 159 } 160 161 /** 162 * Helper method to get the value as a Java long from four bytes starting at given array offset 163 * @param bytes the array of bytes 164 * @param offset the offset to start 165 * @return the corresponding Java long value 166 */ 167 public static long getValue(final byte[] bytes, final int offset) { 168 long value = (bytes[offset + BYTE_3] << BYTE_3_SHIFT) & BYTE_3_MASK; 169 value += (bytes[offset + BYTE_2] << BYTE_2_SHIFT) & BYTE_2_MASK; 170 value += (bytes[offset + BYTE_1] << BYTE_1_SHIFT) & BYTE_1_MASK; 171 value += (bytes[offset] & BYTE_MASK); 172 return value; 173 } 174 175 /** 176 * Helper method to get the value as a Java long from a four-byte array 177 * @param bytes the array of bytes 178 * @return the corresponding Java long value 179 */ 180 public static long getValue(final byte[] bytes) { 181 return getValue(bytes, 0); 182 } 183 184 /** 185 * Override to make two instances with same value equal. 186 * @param o an object to compare 187 * @return true if the objects are equal 188 */ 189 @Override 190 public boolean equals(final Object o) { 191 if (o == null || !(o instanceof ZipLong)) { 192 return false; 193 } 194 return value == ((ZipLong) o).getValue(); 195 } 196 197 /** 198 * Override to make two instances with same value equal. 199 * @return the value stored in the ZipLong 200 */ 201 @Override 202 public int hashCode() { 203 return (int) value; 204 } 205 206 @Override 207 public Object clone() { 208 try { 209 return super.clone(); 210 } catch (final CloneNotSupportedException cnfe) { 211 // impossible 212 throw new RuntimeException(cnfe); //NOSONAR 213 } 214 } 215 216 @Override 217 public String toString() { 218 return "ZipLong value: " + value; 219 } 220}