UUID生成器

[java]代码库

import java.util.UUID;
import java.util.concurrent.atomic.AtomicInteger;


public class UUIDGenerator {
    private static AtomicInteger counter = new AtomicInteger(0);

    public static String getUUID() {
        UUID uuid = UUID.randomUUID();
        String str = uuid.toString();

        // 去掉"-"符号    
        String temp = str.substring(0, 8) + str.substring(9, 13) +
            str.substring(14, 18) + str.substring(19, 23) + str.substring(24);

        return temp;
    }

    /**
     * 长生消息id
     */
    public static Long getAtomicCounter() {
        if (counter.get() > 999999) {
            counter.set(1);
        }

        Long time = System.currentTimeMillis();
        Long returnValue = (time * 2394) + counter.incrementAndGet();

        return returnValue;
    }

    private static long incrementAndGet() {
        return counter.incrementAndGet();
    }

    public static void main(String[] args) {
        System.out.println(getUUID());

        System.out.println(getAtomicCounter());
    }
}