将字节数组转换为长数组。

//package com.nowjava;
/** 
来 自 
nowjava - 时代Java
**/


public class Main {

    public static void main(String[] argv) throws Exception {

        byte[] b = new byte[] { 34, 35, 36, 37, 37, 37, 67, 68, 69 };

        System.out.println(byteArrayToLong(b));

    }


    /**

     * Converts a byte array to a long.

     * @param b - The byte array. Must be a length of at least 8.

     * @return The long.

     */

    public static long byteArrayToLong(byte[] b) {

        return b[7] & 0xFF | (b[6] & 0xFF) << 8 | (b[5] & 0xFF) << 16

                | (b[4] & 0xFF)