Java tutorial
//package com.java2s; /* * 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 * * 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 { /** * Converts a byte array to a long. Halfwords can be swapped by setting * swapHalfWord=true. * * @param number * An array of bytes containing a number * @param swapHalfWord * Swap halfwords ([0][1][2][3]->[1][0][3][2]) * @return The long value * @throws UnsupportedOperationException if number length is not a multiple of 2 */ static long byteArray2long(final byte[] number, final boolean swapHalfWord) { if (number.length % 2 != 0) { throw new UnsupportedOperationException(); } long ret = 0; int pos = 0; byte tmp_number[] = new byte[number.length]; System.arraycopy(number, 0, tmp_number, 0, number.length); if (!swapHalfWord) { byte tmp = 0; for (pos = 0; pos < tmp_number.length; pos++) { tmp = tmp_number[pos]; tmp_number[pos++] = tmp_number[pos]; tmp_number[pos] = tmp; } } ret = tmp_number[0] & 0xFF; for (pos = 1; pos < tmp_number.length; pos++) { ret <<= 8; ret |= tmp_number[pos] & 0xFF; } return ret; } }