java生成全局id的方式

public class TestUUID {
    public static void main(String[] args) {
        System.out.println("UUID.randomUUID() = " + UUID.randomUUID().toString());
        System.out.println("UUID.randomUUID().length = " + UUID.randomUUID().toString().length());

        String s1 = IdUtil.fastUUID();
        System.out.println("fastUUID = " + s1);
        System.out.println("fastUUID().length = " + s1.length());

        String s = IdUtil.fastSimpleUUID();
        System.out.println("fastSimpleUUID = " + s);
        System.out.println("fastSimpleUUID().length = " + s.length());

        String outTradNo = IdUtil.getSnowflake(1L, 1L).nextIdStr();
        System.out.println("getSnowflake = " + outTradNo);
        System.out.println("getSnowflake().length = " + outTradNo.length());

    }
}