public class CustomerCRC32 {    private static long[] crc32Table = new long[256];    static {        long crcValue;        for (int i = 0; i < 256; i++) {            crcValue = i;            for (int j = 0; j < 8; j++) {                if ((crcValue & 1) == 1) {                    crcValue = crcValue >> 1;                    crcValue = 0x00000000edb88320L ^ crcValue;                } else {                    crcValue = crcValue >> 1;                }            }            crc32Table[i] = crcValue;        }    }    public static long getCrc32(byte[] bytes) {        long resultCrcValue = 0x00000000ffffffffL;        for (int i = 0; i < bytes.length; i++) {            int index = (int) ((resultCrcValue ^ bytes[i]) & 0xff);            resultCrcValue = crc32Table[index] ^ (resultCrcValue >> 8);        }        resultCrcValue = resultCrcValue ^ 0x00000000ffffffffL;        return resultCrcValue;    }    public static void main(String[] args) {        String testStr = "{\"log\":{\"content\":\"2\",\"time\":\"2016-01-05 10:17:24\",\"type\":1001,\"version\":\"[5.0.8.12]\"},\"pcInfo\":{\"ip\":\"192.168.118.57\",\"mac\":\"94-DE-80-A8-E6-EC\",\"onlyId\":\"7CE81DDBF7D05F6AD89CD7D79FAA5905\"},\"user\":{\"name\":\"CFM\"}}";        java.util.zip.CRC32 jdkCrc32 = new java.util.zip.CRC32();        jdkCrc32.update(testStr.getBytes());        System.out.println("jdk  crc32: " + jdkCrc32.getValue());        System.out.println("test crc32: " + getCrc32(testStr.getBytes()));    }}