| /* |
| * 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 |
| * |
| * https://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; |
| |
| import static org.apache.tools.zip.ZipConstants.BYTE_MASK; |
| |
| import java.math.BigInteger; |
| |
| /** |
| * Utility class that represents an eight byte integer with conversion |
| * rules for the big endian byte order of ZIP files. |
| */ |
| public final class ZipEightByteInteger { |
| |
| private static final int BYTE_1 = 1; |
| private static final int BYTE_1_MASK = 0xFF00; |
| private static final int BYTE_1_SHIFT = 8; |
| |
| private static final int BYTE_2 = 2; |
| private static final int BYTE_2_MASK = 0xFF0000; |
| private static final int BYTE_2_SHIFT = 16; |
| |
| private static final int BYTE_3 = 3; |
| private static final long BYTE_3_MASK = 0xFF000000L; |
| private static final int BYTE_3_SHIFT = 24; |
| |
| private static final int BYTE_4 = 4; |
| private static final long BYTE_4_MASK = 0xFF00000000L; |
| private static final int BYTE_4_SHIFT = 32; |
| |
| private static final int BYTE_5 = 5; |
| private static final long BYTE_5_MASK = 0xFF0000000000L; |
| private static final int BYTE_5_SHIFT = 40; |
| |
| private static final int BYTE_6 = 6; |
| private static final long BYTE_6_MASK = 0xFF000000000000L; |
| private static final int BYTE_6_SHIFT = 48; |
| |
| private static final int BYTE_7 = 7; |
| private static final long BYTE_7_MASK = 0x7F00000000000000L; |
| private static final int BYTE_7_SHIFT = 56; |
| |
| private static final int LEFTMOST_BIT_SHIFT = 63; |
| private static final byte LEFTMOST_BIT = (byte) 0x80; |
| |
| private final BigInteger value; |
| |
| public static final ZipEightByteInteger ZERO = new ZipEightByteInteger(0); |
| |
| /** |
| * Create instance from a number. |
| * @param value the long to store as a ZipEightByteInteger |
| */ |
| public ZipEightByteInteger(long value) { |
| this(BigInteger.valueOf(value)); |
| } |
| |
| /** |
| * Create instance from a number. |
| * @param value the BigInteger to store as a ZipEightByteInteger |
| */ |
| public ZipEightByteInteger(BigInteger value) { |
| this.value = value; |
| } |
| |
| /** |
| * Create instance from bytes. |
| * @param bytes the bytes to store as a ZipEightByteInteger |
| */ |
| public ZipEightByteInteger(byte[] bytes) { |
| this(bytes, 0); |
| } |
| |
| /** |
| * Create instance from the eight bytes starting at offset. |
| * @param bytes the bytes to store as a ZipEightByteInteger |
| * @param offset the offset to start |
| */ |
| public ZipEightByteInteger(byte[] bytes, int offset) { |
| value = ZipEightByteInteger.getValue(bytes, offset); |
| } |
| |
| /** |
| * Get value as eight bytes in big endian byte order. |
| * @return value as eight bytes in big endian order |
| */ |
| public byte[] getBytes() { |
| return ZipEightByteInteger.getBytes(value); |
| } |
| |
| /** |
| * Get value as Java long. |
| * @return value as a long |
| */ |
| public long getLongValue() { |
| return value.longValue(); |
| } |
| |
| /** |
| * Get value as Java long. |
| * @return value as a long |
| */ |
| public BigInteger getValue() { |
| return value; |
| } |
| |
| /** |
| * Get value as eight bytes in big endian byte order. |
| * @param value the value to convert |
| * @return value as eight bytes in big endian byte order |
| */ |
| public static byte[] getBytes(long value) { |
| return getBytes(BigInteger.valueOf(value)); |
| } |
| |
| /** |
| * Get value as eight bytes in big endian byte order. |
| * @param value the value to convert |
| * @return value as eight bytes in big endian byte order |
| */ |
| public static byte[] getBytes(BigInteger value) { |
| byte[] result = new byte[8]; |
| long val = value.longValue(); |
| result[0] = (byte) ((val & BYTE_MASK)); |
| result[BYTE_1] = (byte) ((val & BYTE_1_MASK) >> BYTE_1_SHIFT); |
| result[BYTE_2] = (byte) ((val & BYTE_2_MASK) >> BYTE_2_SHIFT); |
| result[BYTE_3] = (byte) ((val & BYTE_3_MASK) >> BYTE_3_SHIFT); |
| result[BYTE_4] = (byte) ((val & BYTE_4_MASK) >> BYTE_4_SHIFT); |
| result[BYTE_5] = (byte) ((val & BYTE_5_MASK) >> BYTE_5_SHIFT); |
| result[BYTE_6] = (byte) ((val & BYTE_6_MASK) >> BYTE_6_SHIFT); |
| result[BYTE_7] = (byte) ((val & BYTE_7_MASK) >> BYTE_7_SHIFT); |
| if (value.testBit(LEFTMOST_BIT_SHIFT)) { |
| result[BYTE_7] |= LEFTMOST_BIT; |
| } |
| return result; |
| } |
| |
| /** |
| * Helper method to get the value as a Java long from eight bytes |
| * starting at given array offset |
| * @param bytes the array of bytes |
| * @param offset the offset to start |
| * @return the corresponding Java long value |
| */ |
| public static long getLongValue(byte[] bytes, int offset) { |
| return getValue(bytes, offset).longValue(); |
| } |
| |
| /** |
| * Helper method to get the value as a Java BigInteger from eight |
| * bytes starting at given array offset |
| * @param bytes the array of bytes |
| * @param offset the offset to start |
| * @return the corresponding Java BigInteger value |
| */ |
| public static BigInteger getValue(byte[] bytes, int offset) { |
| long value = ((long) bytes[offset + BYTE_7] << BYTE_7_SHIFT) & BYTE_7_MASK; |
| value += ((long) bytes[offset + BYTE_6] << BYTE_6_SHIFT) & BYTE_6_MASK; |
| value += ((long) bytes[offset + BYTE_5] << BYTE_5_SHIFT) & BYTE_5_MASK; |
| value += ((long) bytes[offset + BYTE_4] << BYTE_4_SHIFT) & BYTE_4_MASK; |
| value += ((long) bytes[offset + BYTE_3] << BYTE_3_SHIFT) & BYTE_3_MASK; |
| value += ((long) bytes[offset + BYTE_2] << BYTE_2_SHIFT) & BYTE_2_MASK; |
| value += ((long) bytes[offset + BYTE_1] << BYTE_1_SHIFT) & BYTE_1_MASK; |
| value += ((long) bytes[offset] & BYTE_MASK); |
| BigInteger val = BigInteger.valueOf(value); |
| return (bytes[offset + BYTE_7] & LEFTMOST_BIT) == LEFTMOST_BIT |
| ? val.setBit(LEFTMOST_BIT_SHIFT) : val; |
| } |
| |
| /** |
| * Helper method to get the value as a Java long from an eight-byte array |
| * @param bytes the array of bytes |
| * @return the corresponding Java long value |
| */ |
| public static long getLongValue(byte[] bytes) { |
| return getLongValue(bytes, 0); |
| } |
| |
| /** |
| * Helper method to get the value as a Java long from an eight-byte array |
| * @param bytes the array of bytes |
| * @return the corresponding Java BigInteger value |
| */ |
| public static BigInteger getValue(byte[] bytes) { |
| return getValue(bytes, 0); |
| } |
| |
| /** |
| * Override to make two instances with same value equal. |
| * @param o an object to compare |
| * @return true if the objects are equal |
| */ |
| @Override |
| public boolean equals(Object o) { |
| return o instanceof ZipEightByteInteger |
| && value.equals(((ZipEightByteInteger) o).getValue()); |
| } |
| |
| /** |
| * Override to make two instances with same value equal. |
| * @return the hashCode of the value stored in the ZipEightByteInteger |
| */ |
| @Override |
| public int hashCode() { |
| return value.hashCode(); |
| } |
| |
| @Override |
| public String toString() { |
| return "ZipEightByteInteger value: " + value; |
| } |
| } |