java 並發生成商品編號

import java.time.Instant;
import java.util.HashSet;
import java.util.Set;
import java.util.UUID;
import java.util.concurrent.Callable;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.FutureTask;
import java.util.concurrent.ThreadLocalRandom;
import java.util.concurrent.atomic.AtomicInteger;

import org.apache.commons.lang3.StringUtils;
import org.apache.commons.lang3.time.FastDateFormat;

/**
 * 訂單編號策略
 * 
 * @project common-utils
 * @fileName ODDGenerator.java
 * @Description
 * @author light-zhang
 * @date 2018年5月11日
 * @version 1.0.0
 */
public abstract class ODDGenerator {
    private static final FastDateFormat pattern = FastDateFormat.getInstance("yyyyMMddHHmmss");
    private static final AtomicInteger atomicInteger = new AtomicInteger(1);
    private static ThreadLocal<StringBuilder> threadLocal = new ThreadLocal<StringBuilder>();

    /**
     * 【長碼生成策略】
     * 
     * @時間20180511231532
     * @二位隨機數
     * @lock的hash-code編碼
     * @param lock 生成的UUID32位參數
     * @return 長碼機制
     */
    public static String getC(String lock) {
        StringBuilder builder = new StringBuilder(pattern.format(Instant.now().toEpochMilli()));// 取系統當前時間作為訂單號前半部分
        builder.append(Math.abs(lock.hashCode()));// HASH-CODE
        builder.append(atomicInteger.getAndIncrement());// 自增順序
        threadLocal.set(builder);
        return threadLocal.get().toString();
    }

    /**
     * 【短碼生成策略】
     * 
     * @param lock
     * @return
     */
    public static String getD(String lock) {
        StringBuilder builder = new StringBuilder(ThreadLocalRandom.current().nextInt(0,999));// 隨機數
        builder.append(Math.abs(lock.hashCode()));// HASH-CODE
        builder.append(atomicInteger.getAndIncrement());// 自增順序
        threadLocal.set(builder);
        return threadLocal.get().toString();
    }

    /**
     * 1000個線程並發測試
     * 
     * @param args
     * @throws InterruptedException
     * @throws ExecutionException
     */
    public static void main(String[] args) throws InterruptedException, ExecutionException {
        Set<String> set = new HashSet<String>();
        FutureTask<String> task = null;
        long startTime = System.currentTimeMillis();
        for (int i = 0; i <1; i++) {
            Callable<String> callable = new Callable<String>() {
                @Override
                public String call() throws Exception {
                    // System.out.println("當前線程:>>>>> ".concat(Thread.currentThread().getName()));
                    // return getC(StringUtils.replace(UUID.randomUUID().toString(), "-", ""));
                    return getD(StringUtils.replace(UUID.randomUUID().toString(), "-", ""));
                }
            };
            task = new FutureTask<String>(callable);
            new Thread(task).start();
            //System.out.println(task.get());
            set.add(task.get());
        }
        System.out.println("總共耗時:" + ((System.currentTimeMillis() - startTime)) + "ms");
        System.out.println("*************** " + set.size());
    } 
}