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常用工具類一

一 .  Base64Util

package com.jarvis.base.util;

import java.io.*;

/**   
* @Title: Base64Util.java 
* @Package com.jarvis.base.util 
* @Description:Base64工具類
* @author Jack  
* @date 2017年9月2日 下午5:10:32 
* @version V1.0   
*/ 
public final class Base64Util
{
    private
static final int BASELENGTH = 255; private static final int LOOKUPLENGTH = 64; private static final int TWENTYFOURBITGROUP = 24; private static final int EIGHTBIT = 8; private static final int SIXTEENBIT = 16; // private static final int SIXBIT = 6; private static final int
FOURBYTE = 4; // private static final int TWOBYTE = 2; private static final int SIGN = -128; private static final byte PAD = (byte) '='; private static byte[] base64Alphabet = new byte[BASELENGTH]; private static byte[] lookUpBase64Alphabet = new byte[LOOKUPLENGTH]; static
{ for (int i = 0; i < BASELENGTH; i++) { base64Alphabet[i] = -1; } for (int i = 'Z'; i >= 'A'; i--) { base64Alphabet[i] = (byte) (i - 'A'); } for (int i = 'z'; i >= 'a'; i--) { base64Alphabet[i] = (byte) (i - 'a' + 26); } for (int i = '9'; i >= '0'; i--) { base64Alphabet[i] = (byte) (i - '0' + 52); } base64Alphabet['+'] = 62; base64Alphabet['/'] = 63; for (int i = 0; i <= 25; i++) { lookUpBase64Alphabet[i] = (byte) ('A' + i); } for (int i = 26, j = 0; i <= 51; i++, j++) { lookUpBase64Alphabet[i] = (byte) ('a' + j); } for (int i = 52, j = 0; i <= 61; i++, j++) { lookUpBase64Alphabet[i] = (byte) ('0' + j); } lookUpBase64Alphabet[62] = (byte) '+'; lookUpBase64Alphabet[63] = (byte) '/'; } public static boolean isBase64(String isValidString) { return isArrayByteBase64(isValidString.getBytes()); } public static boolean isBase64(byte octect) { // shall we ignore white space? JEFF?? return (octect == PAD || base64Alphabet[octect] != -1); } public static boolean isArrayByteBase64(byte[] arrayOctect) { int length = arrayOctect.length; if (length == 0) { // shouldn't a 0 length array be valid base64 data? // return false; return true; } for (int i = 0; i < length; i++) { if (!isBase64(arrayOctect[i])) { return false; } } return true; } /** * Encode String object; * * @param src String object to be encoded. * @return encoded String; */ public static String encodeString(String src) { return encode(src); } public static String encodeBytes(byte[] src) { if (src == null || src.length == 0) { return null; } byte[] bytes = encode(src); return new String(bytes); } /** * Encode String object; * * @param src String object to be encoded. * @return encoded String; */ public static String encode(String src) { String target = null; if (src != null) { byte[] bts1 = src.getBytes(); byte[] bts2 = encode(bts1); if (bts2 != null) { target = new String(bts2); } } return target; } /** * Encodes hex octects into Base64. * * @param binaryData Array containing binary data to encode. * @return Base64-encoded data. */ public static byte[] encode(byte[] binaryData) { int lengthDataBits = binaryData.length * EIGHTBIT; int fewerThan24bits = lengthDataBits % TWENTYFOURBITGROUP; int numberTriplets = lengthDataBits / TWENTYFOURBITGROUP; byte encodedData[] = null; if (fewerThan24bits != 0) { // data not divisible by 24 bit encodedData = new byte[(numberTriplets + 1) * 4]; } else { // 16 or 8 bit encodedData = new byte[numberTriplets * 4]; } byte k = 0, l = 0, b1 = 0, b2 = 0, b3 = 0; int encodedIndex = 0; int dataIndex = 0; int i = 0; for (i = 0; i < numberTriplets; i++) { dataIndex = i * 3; b1 = binaryData[dataIndex]; b2 = binaryData[dataIndex + 1]; b3 = binaryData[dataIndex + 2]; l = (byte) (b2 & 0x0f); k = (byte) (b1 & 0x03); encodedIndex = i * 4; byte val1 = ((b1 & SIGN) == 0) ? (byte) (b1 >> 2) : (byte) ((b1) >> 2 ^ 0xc0); byte val2 = ((b2 & SIGN) == 0) ? (byte) (b2 >> 4) : (byte) ((b2) >> 4 ^ 0xf0); byte val3 = ((b3 & SIGN) == 0) ? (byte) (b3 >> 6) : (byte) ((b3) >> 6 ^ 0xfc); encodedData[encodedIndex] = lookUpBase64Alphabet[val1]; encodedData[encodedIndex + 1] = lookUpBase64Alphabet[val2 | (k << 4)]; encodedData[encodedIndex + 2] = lookUpBase64Alphabet[(l << 2) | val3]; encodedData[encodedIndex + 3] = lookUpBase64Alphabet[b3 & 0x3f]; } // form integral number of 6-bit groups dataIndex = i * 3; encodedIndex = i * 4; if (fewerThan24bits == EIGHTBIT) { b1 = binaryData[dataIndex]; k = (byte) (b1 & 0x03); byte val1 = ((b1 & SIGN) == 0) ? (byte) (b1 >> 2) : (byte) ((b1) >> 2 ^ 0xc0); encodedData[encodedIndex] = lookUpBase64Alphabet[val1]; encodedData[encodedIndex + 1] = lookUpBase64Alphabet[k << 4]; encodedData[encodedIndex + 2] = PAD; encodedData[encodedIndex + 3] = PAD; } else if (fewerThan24bits == SIXTEENBIT) { b1 = binaryData[dataIndex]; b2 = binaryData[dataIndex + 1]; l = (byte) (b2 & 0x0f); k = (byte) (b1 & 0x03); byte val1 = ((b1 & SIGN) == 0) ? (byte) (b1 >> 2) : (byte) ((b1) >> 2 ^ 0xc0); byte val2 = ((b2 & SIGN) == 0) ? (byte) (b2 >> 4) : (byte) ((b2) >> 4 ^ 0xf0); encodedData[encodedIndex] = lookUpBase64Alphabet[val1]; encodedData[encodedIndex + 1] = lookUpBase64Alphabet[val2 | (k << 4)]; encodedData[encodedIndex + 2] = lookUpBase64Alphabet[l << 2]; encodedData[encodedIndex + 3] = PAD; } return encodedData; } public static String decode(String src) { String target = null; if (src != null) { byte[] bts1 = src.getBytes(); byte[] bts2 = decode(bts1); if (bts2 != null) { target = new String(bts2); } } return target; } public static String decode(String src, String charSet) throws UnsupportedEncodingException { String target = null; if (src != null) { byte[] bts1 = src.getBytes(); byte[] bts2 = decode(bts1); if (bts2 != null) { target = new String(bts2, charSet); } } return target; } /** * Decodes Base64 data into octects * * @param base64Data Byte array containing Base64 data * @return Array containing decoded data. */ public static byte[] decode(byte[] base64Data) { // handle the edge case, so we don't have to worry about it later if (base64Data.length == 0) { return null; } int numberQuadruple = base64Data.length / FOURBYTE; byte decodedData[] = null; byte b1 = 0, b2 = 0, b3 = 0, b4 = 0, marker0 = 0, marker1 = 0; // Throw away anything not in base64Data int encodedIndex = 0; int dataIndex = 0; { // this sizes the output array properly - rlw int lastData = base64Data.length; // ignore the '=' padding while (base64Data[lastData - 1] == PAD) { if (--lastData == 0) { return new byte[0]; } } decodedData = new byte[lastData - numberQuadruple]; } for (int i = 0; i < numberQuadruple; i++) { dataIndex = i * 4; marker0 = base64Data[dataIndex + 2]; marker1 = base64Data[dataIndex + 3]; b1 = base64Alphabet[base64Data[dataIndex]]; b2 = base64Alphabet[base64Data[dataIndex + 1]]; if (marker0 != PAD && marker1 != PAD) { // No PAD e.g 3cQl b3 = base64Alphabet[marker0]; b4 = base64Alphabet[marker1]; decodedData[encodedIndex] = (byte) (b1 << 2 | b2 >> 4); decodedData[encodedIndex + 1] = (byte) (((b2 & 0xf) << 4) | ((b3 >> 2) & 0xf)); decodedData[encodedIndex + 2] = (byte) (b3 << 6 | b4); } else if (marker0 == PAD) { // Two PAD e.g. 3c[Pad][Pad] decodedData[encodedIndex] = (byte) (b1 << 2 | b2 >> 4); } else if (marker1 == PAD) { // One PAD e.g. 3cQ[Pad] b3 = base64Alphabet[marker0]; decodedData[encodedIndex] = (byte) (b1 << 2 | b2 >> 4); decodedData[encodedIndex + 1] = (byte) (((b2 & 0xf) << 4) | ((b3 >> 2) & 0xf)); } encodedIndex += 3; } return decodedData; } /** * 隱藏工具類的構造方法 */ protected Base64Util() { throw new UnsupportedOperationException(); } /** * 檔案讀取緩衝區大小 */ private static final int CACHE_SIZE = 1024; /** *//** * <p> * BASE64字串解碼為二進位制資料 * </p> * * @param base64 * @return * @throws Exception */ public static byte[] decodeString(String base64) throws Exception { return Base64Util.decode(base64.getBytes()); } /** *//** * <p> * 二進位制資料編碼為BASE64字串 * </p> * * @param bytes * @return * @throws Exception */ public static String encodeByte(byte[] bytes) throws Exception { return new String(Base64Util.encode(bytes)); } /** *//** * <p> * 將檔案編碼為BASE64字串 * </p> * <p> * 大檔案慎用,可能會導致記憶體溢位 * </p> * * @param filePath 檔案絕對路徑 * @return * @throws Exception */ public static String encodeFile(String filePath) throws Exception { byte[] bytes = fileToByte(filePath); return encodeByte(bytes); } /** *//** * <p> * BASE64字串轉回檔案 * </p> * * @param filePath 檔案絕對路徑 * @param base64 編碼字串 * @throws Exception */ public static void decodeToFile(String filePath, String base64) throws Exception { byte[] bytes = decodeString(base64); byteArrayToFile(bytes, filePath); } /** *//** * <p> * 檔案轉換為二進位制陣列 * </p> * * @param filePath 檔案路徑 * @return * @throws Exception */ public static byte[] fileToByte(String filePath) throws Exception { byte[] data = new byte[0]; File file = new File(filePath); if (file.exists()) { FileInputStream in = new FileInputStream(file); ByteArrayOutputStream out = new ByteArrayOutputStream(2048); byte[] cache = new byte[CACHE_SIZE]; int nRead = 0; while ((nRead = in.read(cache)) != -1) { out.write(cache, 0, nRead); out.flush(); } out.close(); in.close(); data = out.toByteArray(); } return data; } /** *//** * <p> * 二進位制資料寫檔案 * </p> * * @param bytes 二進位制資料 * @param filePath 檔案生成目錄 */ public static void byteArrayToFile(byte[] bytes, String filePath) throws Exception { InputStream in = new ByteArrayInputStream(bytes); File destFile = new File(filePath); if (!destFile.getParentFile().exists()) { destFile.getParentFile().mkdirs(); } destFile.createNewFile(); OutputStream out = new FileOutputStream(destFile); byte[] cache = new byte[CACHE_SIZE]; int nRead = 0; while ((nRead = in.read(cache)) != -1) { out.write(cache, 0, nRead); out.flush(); } out.close(); in.close(); } }

二.  FastJsonUtil

package com.jarvis.base.util;

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.util.List;
import java.util.Map;

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONObject;
import com.alibaba.fastjson.TypeReference;
import com.alibaba.fastjson.serializer.JSONLibDataFormatSerializer;
import com.alibaba.fastjson.serializer.SerializeConfig;
import com.alibaba.fastjson.serializer.SerializerFeature;

/**
 *   
 * 
 * @Title: FastJsonUtil.java
 * @Package com.jarvis.base.util
 * @Description:fastjson工具類
 * @author Jack 
 * @date 2017年9月2日 下午4:16:27
 * @version V1.0  
 */
public class FastJsonUtil {

    private static final SerializeConfig config;

    static {
        config = new SerializeConfig();
        config.put(java.util.Date.class, new JSONLibDataFormatSerializer()); // 使用和json-lib相容的日期輸出格式
        config.put(java.sql.Date.class, new JSONLibDataFormatSerializer()); // 使用和json-lib相容的日期輸出格式
    }

    private static final SerializerFeature[] features = { SerializerFeature.WriteMapNullValue, // 輸出空置欄位
            SerializerFeature.WriteNullListAsEmpty, // list欄位如果為null,輸出為[],而不是null
            SerializerFeature.WriteNullNumberAsZero, // 數值欄位如果為null,輸出為0,而不是null
            SerializerFeature.WriteNullBooleanAsFalse, // Boolean欄位如果為null,輸出為false,而不是null
            SerializerFeature.WriteNullStringAsEmpty, // 字元型別欄位如果為null,輸出為"",而不是null
            SerializerFeature.PrettyFormat  //是否需要格式化輸出Json資料
    };

    /**
     * Author:Jack Time:2017年9月2日下午4:24:14
     * 
     * @param object
     * @return Return:String Description:將物件轉成成Json物件
     */
    public static String toJSONString(Object object) {
        return JSON.toJSONString(object, config, features);
    }

    /**
     * Author:Jack Time:2017年9月2日下午4:27:25
     * 
     * @param object
     * @return Return:String Description:使用和json-lib相容的日期輸出格式
     */
    public static String toJSONNoFeatures(Object object) {
        return JSON.toJSONString(object, config);
    }

    /**
     * Author:Jack Time:2017年9月2日下午4:24:54
     * 
     * @param jsonStr
     * @return Return:Object Description:將Json資料轉換成JSONObject
     */
    public static JSONObject toJsonObj(String jsonStr) {
        return (JSONObject) JSON.parse(jsonStr);
    }
    
    /**
     * Author:Jack Time:2017年9月2日下午4:25:20
     * 
     * @param jsonStr
     * @param clazz
     * @return Return:T Description:將Json資料轉換成Object
     */
    public static <T> T toBean(String jsonStr, Class<T> clazz) {
        return JSON.parseObject(jsonStr, clazz);
    }

    /**
     * Author:Jack Time:2017年9月2日下午4:25:34
     * 
     * @param jsonStr
     * @return Return:Object[] Description:將Json資料轉換為陣列
     */
    public static <T> Object[] toArray(String jsonStr) {
        return toArray(jsonStr, null);
    }

    /**
     * Author:Jack Time:2017年9月2日下午4:25:57
     * 
     * @param jsonStr
     * @param clazz
     * @return Return:Object[] Description:將Json資料轉換為陣列
     */
    public static <T> Object[] toArray(String jsonStr, Class<T> clazz) {
        return JSON.parseArray(jsonStr, clazz).toArray();
    }

    /**
     * Author:Jack Time:2017年9月2日下午4:26:08
     * 
     * @param jsonStr
     * @param clazz
     * @return Return:List<T> Description:將Json資料轉換為List
     */
    public static <T> List<T> toList(String jsonStr, Class<T> clazz) {
        return JSON.parseArray(jsonStr, clazz);
    }

    /**
     * 將javabean轉化為序列化的JSONObject物件
     * 
     * @param keyvalue
     * @return
     */
    public static JSONObject beanToJsonObj(Object bean) {
        String jsonStr = JSON.toJSONString(bean);
        JSONObject objectJson = (JSONObject) JSON.parse(jsonStr);
        return objectJson;
    }
    /**
     * json字串轉化為map
     * 
     * @param s
     * @return
     */
    public static Map<?, ?> stringToCollect(String jsonStr) {
        Map<?, ?> map = JSONObject.parseObject(jsonStr);
        return map;
    }

    /**
     * 將map轉化為string
     * 
     * @param m
     * @return
     */
    public static String collectToString(Map<?, ?> map) {
        String jsonStr = JSONObject.toJSONString(map);
        return jsonStr;
    }

    /**
     * Author:Jack Time:2017年9月2日下午4:19:00
     * 
     * @param t
     * @param file
     * @throws IOException
     *             Return:void Description:將物件的Json資料寫入檔案。
     */
    public static <T> void writeJsonToFile(T t, File file) throws IOException {
        String jsonStr = JSONObject.toJSONString(t, SerializerFeature.PrettyFormat);
        BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(file)));
        bw.write(jsonStr);
        bw.close();
    }

    /**
     * Author:Jack Time:2017年9月2日下午4:19:12
     * 
     * @param t
     * @param filename
     * @throws IOException
     *             Return:void Description:將物件的Json資料寫入檔案。
     */
    public static <T> void writeJsonToFile(T t, String filename) throws IOException {
        writeJsonToFile(t, new File(filename));
    }

    /**
     * Author:Jack Time:2017年9月2日下午4:22:07
     * 
     * @param cls
     * @param file
     * @return
     * @throws IOException
     *             Return:T Description:將檔案中的Json資料轉換成Object物件
     */
    public static <T> T readJsonFromFile(Class<T> cls, File file) throws IOException {
        StringBuilder strBuilder = new StringBuilder();
        BufferedReader br = new BufferedReader(new InputStreamReader(new FileInputStream(file)));
        String line = null;
        while ((line = br.readLine()) != null) {
            strBuilder.append(line);
        }
        br.close();
        return JSONObject.parseObject(strBuilder.toString(), cls);
    }

    /**
     * Author:Jack Time:2017年9月2日下午4:22:30
     * 
     * @param cls
     * @param filename
     * @return
     * @throws IOException
     *             Return:T Description:將檔案中的Json資料轉換成Object物件
     */
    public static <T> T readJsonFromFile(Class<T> cls, String filename) throws IOException {
        return readJsonFromFile(cls, new File(filename));
    }

    /**
     * Author:Jack Time:2017年9月2日下午4:23:06
     * 
     * @param typeReference
     * @param file
     * @return
     * @throws IOException
     *             Return:T Description:從檔案中讀取出Json物件
     */
    public static <T> T readJsonFromFile(TypeReference<T> typeReference, File file) throws IOException {
        StringBuilder strBuilder = new StringBuilder();
        BufferedReader br = new BufferedReader(new InputStreamReader(new FileInputStream(file)));
        String line = null;
        while ((line = br.readLine()) != null) {
            strBuilder.append(line);
        }
        br.close();
        return JSONObject.parseObject(strBuilder.toString(), typeReference);
    }

    /**
     * Author:Jack Time:2017年9月2日下午4:23:11
     * 
     * @param typeReference
     * @param filename
     * @return
     * @throws IOException
     *             Return:T Description:從檔案中讀取出Json物件
     */
    public static <T> T readJsonFromFile(TypeReference<T> typeReference, String filename) throws IOException {
        return readJsonFromFile(typeReference, new File(filename));
    }

}

三. ImageHelper

package com.jarvis.base.util;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import net.coobird.thumbnailator.Thumbnails;
import sun.misc.BASE64Decoder;
import sun.misc.BASE64Encoder;

/**
 *   
 * 
 * @Title: ImageHelper.java
 * @Package com.jarvis.base.util
 * @Description:圖片處理工具類。
 * @author Jack 
 * @date 2017年9月2日 下午3:04:40
 * @version V1.0  
 */
@SuppressWarnings("restriction")
public class ImageHelper {
    /**
     * @描述:Base64解碼並生成圖片
     * @入參:@param imgStr
     * @入參:@param imgFile
     * @入參:@throws IOException
     * @出參:void
     */
    public static void generateImage(String imgStr, String imgFile) throws IOException {
        BASE64Decoder decoder = new BASE64Decoder();
        // Base64解碼
        byte[] bytes;
        OutputStream out = null;
        try {
            bytes = decoder.decodeBuffer(imgStr);
            for (int i = 0; i < bytes.length; ++i) {
                if (bytes[i] < 0) {// 調整異常資料
                    bytes[i] += 256;
                }
            }
            // 生成圖片
            out = new FileOutputStream(imgFile);
            out.write(bytes);
            out.flush();
        } catch (IOException e) {
            throw new IOException();
        } finally {
            if (out != null) {
                try {
                    out.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }

    }

    /**
     * @throws IOException
     * @描述:根據路徑得到base編碼後圖片
     * @入參:@param imgFilePath
     * @入參:@return
     * @出參:String
     */
    public static String getImageStr(String imgFilePath) throws IOException {// 將圖片檔案轉化為位元組陣列字串,並對其進行Base64編碼處理
        byte[] data = null;

        // 讀取圖片位元組陣列
        try {
            InputStream in = new FileInputStream(imgFilePath);
            data = new byte[in.available()];
            in.read(data);
            in.close();
        } catch (IOException e) {
            throw new IOException();
        }

        // 對位元組陣列Base64編碼
        BASE64Encoder encoder = new BASE64Encoder();
        return encoder.encode(data);// 返回Base64編碼過的位元組陣列字串
    }

    /**
     * @throws IOException
     * @描述:圖片旋轉
     * @入參:@param base64In 傳入的圖片base64
     * @入參:@param angle 圖片旋轉度數
     * @入參:@throws Exception
     * @出參:String 傳出的圖片base64
     */
    public static String imgAngleRevolve(String base64In, int angle) throws IOException {
        ByteArrayOutputStream os = new ByteArrayOutputStream();
        try {
            Thumbnails.of(base64ToIo(base64In)).scale(1.0).rotate(angle).toOutputStream(os);
        } catch (IOException e) {
            throw new IOException();
        }
        byte[] bs = os.toByteArray();
        String s = new BASE64Encoder().encode(bs);
        return s;
    }

    /**
     * @描述:base64轉為io流
     * @入參:@param strBase64
     * @入參:@return
     * @入參:@throws IOException
     * @出參:InputStream
     */
    public static InputStream base64ToIo(String strBase64) throws IOException {
        // 解碼,然後將位元組轉換為檔案
        byte[] bytes = new BASE64Decoder().decodeBuffer(strBase64); // 將字串轉換為byte陣列
        return new ByteArrayInputStream(bytes);
    }
}

四. UUID

package com.jarvis.base.util;

import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;

/**
 * A class that represents an immutable universally unique identifier (UUID).
 * A UUID represents a 128-bit value.
 * <p/>
 * <p>There exist different variants of these global identifiers. The methods
 * of this class are for manipulating the Leach-Salz variant, although the
 * constructors allow the creation of any variant of UUID (described below).
 * <p/>
 * <p>The layout of a variant 2 (Leach-Salz) UUID is as follows:
 * <p/>
 * The most significant long consists of the following unsigned fields:
 * <pre>
 * 0xFFFFFFFF00000000 time_low
 * 0x00000000FFFF0000 time_mid
 * 0x000000000000F000 version
 * 0x0000000000000FFF time_hi
 * </pre>
 * The least significant long consists of the following unsigned fields:
 * <pre>
 * 0xC000000000000000 variant
 * 0x3FFF000000000000 clock_seq
 * 0x0000FFFFFFFFFFFF node
 * </pre>
 * <p/>
 * <p>The variant field contains a value which identifies the layout of
 * the <tt>UUID</tt>. The bit layout described above is valid only for
 * a <tt>UUID</tt> with a variant value of 2, which indicates the
 * Leach-Salz variant.
 * <p/>
 * <p>The version field holds a value that describes the type of this
 * <tt>UUID</tt>. There are four different basic types of UUIDs: time-based,
 * DCE security, name-based, and randomly generated UUIDs. These types
 * have a version value of 1, 2, 3 and 4, respectively.
 * <p/>
 * <p>For more information including algorithms used to create <tt>UUID</tt>s,
 * see the Internet-Draft <a href="http://www.ietf.org/internet-drafts/draft-mealling-uuid-urn-03.txt">UUIDs and GUIDs</a>
 * or the standards body definition at
 * <a href="http://www.iso.ch/cate/d2229.html">ISO/IEC 11578:1996</a>.
 *
 * @version 1.14, 07/12/04
 * @since 1.5
 */
@Deprecated
public final class UUID implements java.io.Serializable
{

    /**
     * Explicit serialVersionUID for interoperability.
     */
    private static final long serialVersionUID = -4856846361193249489L;

    /*
     * The most significant 64 bits of this UUID.
     *
     * @serial
     */
    private final long mostSigBits;

    /**
     * The least significant 64 bits of this UUID.
     *
     * @serial
     */
    private final long leastSigBits;

    /*
     * The version number associated with this UUID. Computed on demand.
     */
    private transient int version = -1;

    /*
     * The variant number associated with this UUID. Computed on demand.
     */
    private transient int variant = -1;

    /*
     * The timestamp associated with this UUID. Computed on demand.
     */
    private transient volatile long timestamp = -1;

    /*
     * The clock sequence associated with this UUID. Computed on demand.
     */
    private transient int sequence = -1;

    /*
     * The node number associated with this UUID. Computed on demand.
     */
    private transient long node = -1;

    /*
     * The hashcode of this UUID. Computed on demand.
     */
    private transient int hashCode = -1;

    /*
     * The random number generator used by this class to create random
     * based UUIDs.
     */
    private static volatile SecureRandom numberGenerator = null;

    // Constructors and Factories

    /*
     * Private constructor which uses a byte array to construct the new UUID.
     */
    private UUID(byte[] data)
    {
        long msb = 0;
        long lsb = 0;
        for (int i = 0; i < 8; i++)
            msb = (msb << 8) | (data[i] & 0xff);
        for (int i = 8; i < 16; i++)
            lsb = (lsb << 8) | (data[i] & 0xff);
        this.mostSigBits = msb;
        this.leastSigBits = lsb;
    }

    /**
     * Constructs a new <tt>UUID</tt> using the specified data.
     * <tt>mostSigBits</tt> is used for the most significant 64 bits
     * of the <tt>UUID</tt> and <tt>leastSigBits</tt> becomes the
     * least significant 64 bits of the <tt>UUID</tt>.
     *
     * @param mostSigBits
     * @param leastSigBits
     */
    public UUID(long mostSigBits, long leastSigBits)
    {
        this.mostSigBits = mostSigBits;
        this.leastSigBits = leastSigBits;
    }

    /**
     * Static factory to retrieve a type 4 (pseudo randomly generated) UUID.
     * <p/>
     * The <code>UUID</code> is generated using a cryptographically strong
     * pseudo random number generator.
     *
     * @return a randomly generated <tt>UUID</tt>.
     */
    @SuppressWarnings("unused")
    public static UUID randomUUID()
    {
        SecureRandom ng = numberGenerator;
        if (ng == null)
        {
            numberGenerator = ng = new SecureRandom();
        }

        byte[] randomBytes = new byte[16];
        ng.nextBytes(randomBytes);
        randomBytes[6] &= 0x0f;  /* clear version        */
        randomBytes[6] |= 0x40;  /* set to version 4     */
        randomBytes[8] &= 0x3f;  /* clear variant        */
        randomBytes[8] |= 0x80;  /* set to IETF variant  */
        UUID result = new UUID(randomBytes);
        return new UUID(randomBytes);
    }

    /**
     * Static factory to retrieve a type 3 (name based) <tt>UUID</tt> based on
     * the specified byte array.
     *
     * @param name a byte array to be used to construct a <tt>UUID</tt>.
     * @return a <tt>UUID</tt> generated from the specified array.
     */
    public static UUID nameUUIDFromBytes(byte[] name)
    {
        MessageDigest md;
        try
        {
            md = MessageDigest.getInstance("MD5");
        }
        catch (NoSuchAlgorithmException nsae)
        {
            throw new InternalError("MD5 not supported");
        }
        byte[] md5Bytes = md.digest(name);
        md5Bytes[6] &= 0x0f;  /* clear version        */
        md5Bytes[6] |= 0x30;  /* set to version 3     */
        md5Bytes[8] &= 0x3f;  /* clear variant        */
        md5Bytes[8] |= 0x80;  /* set to IETF variant  */
        return new UUID(md5Bytes);
    }

    /**
     * Creates a <tt>UUID</tt> from the string standard representation as
     * described in the {@link #toString} method.
     *
     * @param name a string that specifies a <tt>UUID</tt>.
     * @return a <tt>UUID</tt> with the specified value.
     * @throws IllegalArgumentException if name does not conform to the
     *                                  string representation as described in {@link #toString}.
     */
    public static UUID fromString(String name)
    {
        String[] components = name.split("-");
        if (components.length != 5)
            throw new IllegalArgumentException("Invalid UUID string: " + name);
        for (int i = 0; i < 5; i++)
            components[i] = "0x" + components[i];

        long mostSigBits = Long.decode(components[0]).longValue();
        mostSigBits <<= 16;
        mostSigBits |= Long.decode(components[1]).longValue();
        mostSigBits <<= 16;
        mostSigBits |= Long.decode(components[2]).longValue();

        long leastSigBits = Long.decode(components[3]).longValue();
        leastSigBits <<= 48;
        leastSigBits |= Long.decode(components[4]).longValue();

        return new UUID(mostSigBits, leastSigBits);
    }

    // Field Accessor Methods

    /**
     * Returns the least significant 64 bits of this UUID's 128 bit value.
     *
     * @return the least significant 64 bits of this UUID's 128 bit value.
     */
    public long getLeastSignificantBits()
    {
        return leastSigBits;
    }

    /**
     * Returns the most significant 64 bits of this UUID's 128 bit value.
     *
     * @return the most significant 64 bits of this UUID's 128 bit value.
     */
    public long getMostSignificantBits()
    {
        return mostSigBits;
    }

    /**
     * The version number associated with this <tt>UUID</tt>. The version
     * number describes how this <tt>UUID</tt> was generated.
     * <p/>
     * The version number has the following meaning:<p>
     * <ul>
     * <li>1    Time-based UUID
     * <li>2    DCE security UUID
     * <li>3    Name-based UUID
     * <li>4    Randomly generated UUID
     * </ul>
     *
     * @return the version number of this <tt>UUID</tt>.
     */
    public int version()
    {
        if (version < 0)
        {
            // Version is bits masked by 0x000000000000F000 in MS long
            version = (int) ((mostSigBits >> 12) & 0x0f);
        }
        return version;
    }

    /**
     * The variant number associated with this <tt>UUID</tt>. The variant
     * number describes the layout of the <tt>UUID</tt>.
     * <p/>
     * The variant number has the following meaning:<p>
     * <ul>
     * <li>0    Reserved for NCS backward compatibility
     * <li>2    The Leach-Salz variant (used by this class)
     * <li>6    Reserved, Microsoft Corporation backward compatibility
     * <li>7    Reserved for future definition
     * </ul>
     *
     * @return the variant number of this <tt>UUID</tt>.
     */
    public int variant()
    {
        if (variant < 0)
        {
            // This field is composed of a varying number of bits
            if ((leastSigBits >>> 63) == 0)
            {
                variant = 0;
            }
            else if ((leastSigBits >>> 62) == 2)
            {
                variant = 2;
            }
            else
            {
                variant = (int) (leastSigBits >>> 61);
            }
        }
        return variant;
    }

    /**
     * The timestamp value associated with this UUID.
     * <p/>
     * <p>The 60 bit timestamp value is constructed from the time_low,
     * time_mid, and time_hi fields of this <tt>UUID</tt>. The resulting
     * timestamp is measured in 100-nanosecond units since midnight,
     * October 15, 1582 UTC.<p>
     * <p/>
     * The timestamp value is only meaningful in a time-based UUID, which
     * has version type 1. If this <tt>UUID</tt> is not a time-based UUID then
     * this method throws UnsupportedOperationException.
     *
     * @throws UnsupportedOperationException if this UUID is not a
     *                                       version 1 UUID.
     */
    public long timestamp()
    {
        if (version() != 1)
        {
            throw new UnsupportedOperationException("Not a time-based UUID");
        }
        long result = timestamp;
        if (result < 0)
        {
            result = (mostSigBits & 0x0000000000000FFFL) << 48;
            result |= ((mostSigBits >> 16) & 0xFFFFL) << 32;
            result |= mostSigBits >>> 32;
            timestamp = result;
        }
        return result;
    }

    /**
     * The clock sequence value associated with this UUID.
     * <p/>
     * <p>The 14 bit clock sequence value is constructed from the clock
     * sequence field of this UUID. The clock sequence field is used to
     * guarantee temporal uniqueness in a time-based UUID.<p>
     * <p/>
     * The  clockSequence value is only meaningful in a time-based UUID, which
     * has version type 1. If this UUID is not a time-based UUID then
     * this method throws UnsupportedOperationException.
     *
     * @return the clock sequence of this <tt>UUID</tt>.
     * @throws UnsupportedOperationException if this UUID is not a
     *                                       version 1 UUID.
     */
    public int clockSequence()
    {
        if (version() != 1)
        {
            throw new UnsupportedOperationException("Not a time-based UUID");
        }
        if (sequence < 0)
        {
            sequence = (int) ((leastSigBits & 0x3FFF000000000000L) >>> 48);
        }
        return sequence;
    }

    /**
     * The node value associated with this UUID.
     * <p/>
     * <p>The 48 bit node value is constructed from the node field of
     * this UUID. This field is intended to hold the IEEE 802 address
     * of the machine that generated this UUID to guarantee spatial
     * uniqueness.<p>
     * <p/>
     * The node value is only meaningful in a time-based UUID, which
     * has version type 1. If this UUID is not a time-based UUID then
     * this method throws UnsupportedOperationException.
     *
     * @return the node value of this <tt>UUID</tt>.
     * @throws UnsupportedOperationException if this UUID is not a
     *                                       version 1 UUID.
     */
    public long node()
    {
        if (version() != 1)
        {
            throw new UnsupportedOperationException("Not a time-based UUID");
        }
        if (node < 0)
        {
            node = leastSigBits & 0x0000FFFFFFFFFFFFL;
        }
        return node;
    }

    // Object Inherited Methods

    /**
     * Returns a <code>String</code> object representing this
     * <code>UUID</code>.
     * <p/>
     * <p>The UUID string representation is as described by this BNF :
     * <pre>
     *  UUID                   = <time_low> "-" <time_mid> "-"
     *                           <time_high_and_version> "-"
     *                           <variant_and_sequence> "-"
     *                           <node>
     *  time_low               = 4*<hexOctet>
     *  time_mid               = 2*<hexOctet>
     *  time_high_and_version  = 2*<hexOctet>
     *  variant_and_sequence   = 2*<hexOctet>
     *  node                   = 6*<hexOctet>
     *  hexOctet               = <hexDigit><hexDigit>
     *  hexDigit               =
     *        "0" | "1" | "2" | "3" | "4" | "5" | "6" | "7" | "8" | "9"
     *        | "a" | "b" | "c" | "d" | "e" | "f"
     *        | "A" | "B" | "C" | "D" | "E" | "F"
     * </pre>
     *
     * @return a string representation of this <tt>UUID</tt>.
     */
    public String toString()
    {
        return (digits(mostSigBits >> 32, 8) + "-" +
                digits(mostSigBits >> 16, 4) + "-" +
                digits(mostSigBits, 4) + "-" +
                digits(leastSigBits >> 48, 4) + "-" +
                digits(leastSigBits, 12));
    }

    /**
     * Returns val represented by the specified number of hex digits.
     */
    private static String digits(long val, int digits)
    {
        long hi = 1L << (digits * 4);
        return Long.toHexString(hi | (val & (hi - 1))).substring(1);
    }

    /**
     * Returns a hash code for this <code>UUID</code>.
     *
     * @return a hash code value for this <tt>UUID</tt>.
     */
    public int hashCode()
    {
        if (hashCode == -1)
        {
            hashCode = (int) ((mostSigBits >> 32) ^
                    mostSigBits ^
                    (leastSigBits >> 32) ^
                    leastSigBits);
        }
        return hashCode;
    }

    /**
     * Compares this object to the specified object.  The result is
     * <tt>true</tt> if and only if the argument is not
     * <tt>null</tt>, is a <tt>UUID</tt> object, has the same variant,
     * and contains the same value, bit for bit, as this <tt>UUID</tt>.
     *
     * @param obj the object to compare with.
     * @return <code>true</code> if the objects are the same;
     *         <code>false</code> otherwise.
     */
    public boolean equals(Object obj)
    {
        if (!(obj instanceof UUID))
            return false;
        if (((UUID) obj).variant() != this.variant())
            return false;
        UUID id = (UUID) obj;
        return (mostSigBits == id.mostSigBits &&
                leastSigBits == id.leastSigBits);
    }

    // Comparison Operations

    /**
     * Compares this UUID with the specified UUID.
     * <p/>
     * <p>The first of two UUIDs follows the second if the most significant
     * field in which the UUIDs differ is greater for the first UUID.
     *
     * @param val <tt>UUID</tt> to which this <tt>UUID</tt> is to be compared.
     * @return -1, 0 or 1 as this <tt>UUID</tt> is less than, equal
     *         to, or greater than <tt>val</tt>.
     */
    public int compareTo(UUID val)
    {
        // The ordering is intentionally set up so that the UUIDs
        // can simply be numerically compared as two numbers
        return (this.mostSigBits < val.mostSigBits ? -1 :
                (this.mostSigBits > val.mostSigBits ? 1 :
                        (this.leastSigBits < val.leastSigBits ? -1 :
                                (this.leastSigBits > val.leastSigBits ? 1 :
                                        0))));
    }

    /**
     * Reconstitute the <tt>UUID</tt> instance from a stream (that is,
     * deserialize it). This is necessary to set the transient fields
     * to their correct uninitialized value so they will be recomputed
     * on demand.
     */
    private void readObject(java.io.ObjectInputStream in)
            throws java.io.IOException, ClassNotFoundException
    {

        in.defaultReadObject();

        // Set "cached computation" fields to their initial values
        version = -1;
        variant = -1;
        timestamp = -1;
        sequence = -1;
        node = -1;
        hashCode = -1;
    }
   
}