Main.java Source code

Introduction

Here is the source code for Main.java

Source

//package com.java2s;
/**
 * Copyright (c) 2012-2013, Michael Yang ?? (www.yangfuhai.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.
 */

public class Main {
    private static final long INITIALCRC = 0xFFFFFFFFFFFFFFFFL;
    private static long[] sCrcTable = new long[256];

    /**
     * A function thats returns a 64-bit crc for string
     *
     * @param in input string
     * @return a 64-bit crc value
     */
    public static final long crc64Long(String in) {
        if (in == null || in.length() == 0) {
            return 0;
        }
        return crc64Long(getBytes(in));
    }

    public static final long crc64Long(byte[] buffer) {
        long crc = INITIALCRC;
        for (int k = 0, n = buffer.length; k < n; ++k) {
            crc = sCrcTable[(((int) crc) ^ buffer[k]) & 0xff] ^ (crc >> 8);
        }
        return crc;
    }

    public static byte[] getBytes(String in) {
        byte[] result = new byte[in.length() * 2];
        int output = 0;
        for (char ch : in.toCharArray()) {
            result[output++] = (byte) (ch & 0xFF);
            result[output++] = (byte) (ch >> 8);
        }
        return result;
    }
}