Java ByteBuffer to Long Array getLong(ByteBuffer byteBuffer, int longIndex)

Description

get Long

License

Apache License

Declaration

public static long getLong(ByteBuffer byteBuffer, int longIndex) 

Method Source Code

//package com.java2s;
/**/*from   w w  w. j  a  v  a2  s  .c  o m*/
 * Copyright (C) 2014-2015 LinkedIn Corp. (pinot-core@linkedin.com)
 *
 * 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.
 */

import java.nio.ByteBuffer;

public class Main {
    public static long getLong(ByteBuffer byteBuffer, int longIndex) {
        int index = longIndex * 8;
        if (index >= byteBuffer.limit()) {
            return 0L;
        }
        if (byteBuffer.limit() >= index + 8) {
            return makeLong(byteBuffer.get(index + 0), byteBuffer.get(index + 1), byteBuffer.get(index + 2),
                    byteBuffer.get(index + 3), byteBuffer.get(index + 4), byteBuffer.get(index + 5),
                    byteBuffer.get(index + 6), byteBuffer.get(index + 7));
        } else {
            byte[] buffer = new byte[8];
            byteBuffer.position(index);
            byteBuffer.get(buffer, 0, byteBuffer.limit() - index);
            return makeLong(buffer[0], buffer[1], buffer[2], buffer[3], buffer[4], buffer[5], buffer[6], buffer[7]);
        }
    }

    static public long makeLong(byte b7, byte b6, byte b5, byte b4, byte b3, byte b2, byte b1, byte b0) {
        return ((((long) b7 & 0xff) << 56) | (((long) b6 & 0xff) << 48) | (((long) b5 & 0xff) << 40)
                | (((long) b4 & 0xff) << 32) | (((long) b3 & 0xff) << 24) | (((long) b2 & 0xff) << 16)
                | (((long) b1 & 0xff) << 8) | (((long) b0 & 0xff) << 0));
    }
}

Related

1. deserializeLongArray(ByteBuffer buffer)
2. getLong(ByteBuffer buffer)
3. getLong(ByteBuffer in)
4. getLong(ByteBuffer longCalculator, byte[] bytes)
5. getLongB(ByteBuffer bb, int index)
6. getLongBE(ByteBuffer b, int start, int end)