Java-生成唯一ID（Sequence）

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package com.bootdo.common.utils;

import org.springframework.stereotype.Component;

import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;

/**
 * @author 张子布
 * @version 1.0
 * @date 2018/8/28
 * @explain:
 */
@Component
public class Sequence {
    private static final long ONE_STEP = 10;
    private static final Lock LOCK = new ReentrantLock();
    private static long lastTime = System.currentTimeMillis();
    private static short lastCount = 0;
    private static int count = 0;

    @SuppressWarnings("finally")
    public static String nextId() {
        LOCK.lock();
        try {
            if (lastCount == ONE_STEP) {
                boolean done = false;
                while (!done) {
                    long now = System.currentTimeMillis();
                    if (now == lastTime) {
                        try {
                            Thread.currentThread();
                            Thread.sleep(1);
                        } catch (java.lang.InterruptedException e) {
                        }
                        continue;
                    } else {
                        lastTime = now;
                        lastCount = 0;
                        done = true;
                    }
                }
            }
            count = lastCount++;
        } finally {
            LOCK.unlock();
            return lastTime + "" + String.format("%03d", count);
        }
    }

    //获得batchNo批次号
    @SuppressWarnings({"finally"})
    public static String getBatchNo() {
        LOCK.lock();
        try {
            if (lastCount == ONE_STEP) {
                boolean done = false;
                while (!done) {
                    long now = System.currentTimeMillis();
                    if (now == lastTime) {
                        try {
                            Thread.currentThread();
                            Thread.sleep(1);
                        } catch (java.lang.InterruptedException e) {
                        }
                        continue;
                    } else {
                        lastTime = now;
                        lastCount = 0;
                        done = true;
                    }
                }
            }
            count = lastCount++;
        } finally {
            LOCK.unlock();
            String str = lastTime + "" + String.format("%03d", count);
            String batchNo = "C"+str.substring(1);
            return batchNo;
        }
    }

    public static void main(String[] args) {
        //测试

            System.out.println(nextId());

    }
}