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 *  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
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package org.apache.commons.compress.archivers.zip;

import java.io.Serializable;
import java.math.BigInteger;

import static org.apache.commons.compress.archivers.zip.ZipConstants.BYTE_MASK;

Utility class that represents an eight byte integer with conversion rules for the little endian byte order of ZIP files.
@Immutable
Since:1.2
/** * Utility class that represents an eight byte integer with conversion * rules for the little endian byte order of ZIP files. * @Immutable * * @since 1.2 */
public final class ZipEightByteInteger implements Serializable { private static final long serialVersionUID = 1L; 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.
Params:
  • value – the long to store as a ZipEightByteInteger
/** * Create instance from a number. * @param value the long to store as a ZipEightByteInteger */
public ZipEightByteInteger(final long value) { this(BigInteger.valueOf(value)); }
Create instance from a number.
Params:
  • value – the BigInteger to store as a ZipEightByteInteger
/** * Create instance from a number. * @param value the BigInteger to store as a ZipEightByteInteger */
public ZipEightByteInteger(final BigInteger value) { this.value = value; }
Create instance from bytes.
Params:
  • bytes – the bytes to store as a ZipEightByteInteger
/** * Create instance from bytes. * @param bytes the bytes to store as a ZipEightByteInteger */
public ZipEightByteInteger (final byte[] bytes) { this(bytes, 0); }
Create instance from the eight bytes starting at offset.
Params:
  • bytes – the bytes to store as a ZipEightByteInteger
  • offset – the offset to start
/** * 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 (final byte[] bytes, final int offset) { value = ZipEightByteInteger.getValue(bytes, offset); }
Get value as eight bytes in big endian byte order.
Returns:value as eight bytes in big endian order
/** * 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.
Returns:value as a long
/** * Get value as Java long. * @return value as a long */
public long getLongValue() { return value.longValue(); }
Get value as Java long.
Returns:value as a long
/** * 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.
Params:
  • value – the value to convert
Returns:value as eight bytes in big endian byte order
/** * 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(final long value) { return getBytes(BigInteger.valueOf(value)); }
Get value as eight bytes in big endian byte order.
Params:
  • value – the value to convert
Returns:value as eight bytes in big endian byte order
/** * 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(final BigInteger value) { final byte[] result = new byte[8]; final 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
Params:
  • bytes – the array of bytes
  • offset – the offset to start
Returns:the corresponding Java long value
/** * 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(final byte[] bytes, final 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
Params:
  • bytes – the array of bytes
  • offset – the offset to start
Returns:the corresponding Java BigInteger value
/** * 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(final byte[] bytes, final 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); final 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
Params:
  • bytes – the array of bytes
Returns:the corresponding Java long value
/** * 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(final byte[] bytes) { return getLongValue(bytes, 0); }
Helper method to get the value as a Java long from an eight-byte array
Params:
  • bytes – the array of bytes
Returns:the corresponding Java BigInteger value
/** * 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(final byte[] bytes) { return getValue(bytes, 0); }
Override to make two instances with same value equal.
Params:
  • o – an object to compare
Returns:true if the objects are equal
/** * 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(final Object o) { if (o == null || !(o instanceof ZipEightByteInteger)) { return false; } return value.equals(((ZipEightByteInteger) o).getValue()); }
Override to make two instances with same value equal.
Returns:the hashCode of the value stored in the ZipEightByteInteger
/** * 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; } }