生产uuid

uuid生产功能

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近端时间要做一个获取唯一流水号的功能，于是有了：ip+starttime+pid+flow的方式。

 import java.lang.management.ManagementFactory;
 import java.math.BigInteger;
 import java.net.InetAddress;
 import java.net.UnknownHostException;
 import java.text.DateFormat;
 import java.text.SimpleDateFormat;
 import java.util.Date;
 import java.util.concurrent.atomic.AtomicLong;

 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;

 /**
  * 获取流水号：ip+starttime+pid+flow
  *
  * //将ip和starttime和pid转化为32进制+流水号
  *
  * @author zhanghw
  */
 public class FlowNum {
     private static final Logger LOGGER = LoggerFactory.getLogger(FlowNum.class);
     private static final String FLOW_NUM_PERFIX;// 流水号前缀
     private static final AtomicLong count = new AtomicLong();
     private static final int radix = 32;// 转换的进制
     private static final DateFormat dateFormat = new SimpleDateFormat("yyyyMMdd-HH:mm:ss-SSS");

     static {
         String ip = getLocalAddress();
         long startTime = System.currentTimeMillis();
         String pid = getPid();
         System.out.printf("ip=%s,pid= %s,startTime= %s", ip, pid, dateFormat.format(new Date(startTime)));
         LOGGER.info("this program ip ={},pid={},starttime={}", ip, pid, dateFormat.format(new Date(startTime)));

         StringBuilder sb = new StringBuilder();
         sb.append(ipToLong(ip)).append(startTime).append(pid);
         // ip(9),starttime(),pid
         System.out.println(sb.toString());

         BigInteger big = new BigInteger(sb.toString());
         String str_32 = big.toString(radix);
         FLOW_NUM_PERFIX = str_32 + "_";
     }

     /**
      * 获取一个流水号
      * @return
      */
     public static String get() {
         return FLOW_NUM_PERFIX + count.incrementAndGet();
     }

     /**
      * 47igkn0n9v03282b9dr8_7
      *
      * @throws Exception
      */
     public static void printInfo(String FLOW_NUM_PERFIX) throws Exception {
         if (FLOW_NUM_PERFIX == null || FLOW_NUM_PERFIX.trim().length() == 0) {
             throw new Exception("the sttring is empty!");
         }
         String perfix = FLOW_NUM_PERFIX.split("_")[0];
         BigInteger perfix_32 = new BigInteger(perfix, radix);// 32进制
         String perfix_10 = perfix_32.toString(10);// 10进制

         String ip_long = perfix_10.substring(0, 9);
         String startTime = perfix_10.substring(9, 22);
         System.out.println(startTime);
         String pid = perfix_10.substring(22, perfix_10.length());

         String ipStr = longToIp(Long.valueOf(ip_long));
         String startTimeStr = dateFormat.format(new Date(Long.valueOf(startTime)));

         System.out.printf("ip=%s,time=%s,pid=%s", ipStr, startTimeStr, pid);
         LOGGER.info("ip={},time={},pid={}", ipStr, startTimeStr, pid);

     }

     /**
      * 获取当前进程id
      *
      * @return
      */
     private static final String getPid() {
         // get name representing the running Java virtual machine.
         String name = ManagementFactory.getRuntimeMXBean().getName();
         String pid = name.split("@")[0];
         return pid;
     }

     /**
      * 获取当前服务器ip
      *
      * @return
      */
     private static final String getLocalAddress() {
         InetAddress addr = null;
         try {
             addr = InetAddress.getLocalHost();
         } catch (UnknownHostException e) {
             e.printStackTrace();
         }

         if (addr == null) {
             return null;
         }

         return addr.getHostAddress();
     }

     /**
      * long转为ip
      *
      * @param ip
      * @return
      */
     private static String longToIp(long ip) {
         return ((ip >> 24) & 0xFF) + "." + ((ip >> 16) & 0xFF) + "." + ((ip >> 8) & 0xFF) + "." + (ip & 0xFF);
     }

     /**
      * ip转为long
      *
      * @param ipAddress
      * @return
      */
     private static long ipToLong(String ipAddress) {
         long result = 0;
         String[] ipAddressInArray = ipAddress.split("\\.");
         for (int i = 3; i >= 0; i--) {
             long ip = Long.parseLong(ipAddressInArray[3 - i]);
             result |= ip << (i * 8);
         }
         return result;
     }

 }