Android Byte Array to Long Convert swap64bitFromArray(byte[] value, int offset)

Description

Reads a signed 64 bit integer from an array coming from a device.

License

Apache License

Parameter

Parameter	Description
value	the array containing the int
offset	the offset in the array at which the int starts Array length must be at least offset + 8

Return

the integer read from the array

Declaration

public static long swap64bitFromArray(byte[] value, int offset) 

Method Source Code

//package com.java2s;
/*/*from w w  w .java  2s .c o m*/
 * Copyright (C) 2007 The Android Open Source Project
 *
 * Licensed 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.
 */

public class Main {
    /**
     * Reads a signed 64 bit integer from an array coming from a device.
     * @param value the array containing the int
     * @param offset the offset in the array at which the int starts
     *      Array length must be at least offset + 8
     * @return the integer read from the array
     */
    public static long swap64bitFromArray(byte[] value, int offset) {
        long v = 0;
        v |= ((long) value[offset]) & 0x00000000000000FFL;
        v |= (((long) value[offset + 1]) & 0x00000000000000FFL) << 8;
        v |= (((long) value[offset + 2]) & 0x00000000000000FFL) << 16;
        v |= (((long) value[offset + 3]) & 0x00000000000000FFL) << 24;
        v |= (((long) value[offset + 4]) & 0x00000000000000FFL) << 32;
        v |= (((long) value[offset + 5]) & 0x00000000000000FFL) << 40;
        v |= (((long) value[offset + 6]) & 0x00000000000000FFL) << 48;
        v |= (((long) value[offset + 7]) & 0x00000000000000FFL) << 56;

        return v;
    }
}

Related

1. toLong(byte[] in)
2. parseLong(byte[] b, int start, int end, int radix)
3. parseLong(byte[] b, int start, int end)
4. bytes2long(byte[] b)