public class RandomIDUtils {

private static final long LIMIT = 1000000000L;
private static long last = 0;
// 集群环境下修改此 workerId(1,2,3 依次递增)
private static final long workerId = 1;

/**
* 生成 10 位不重复数字, 首位为 workerId
* 线程安全
* 单调递增
*/
public static long getID() {
long id = System.currentTimeMillis() % LIMIT;
if (id <= last) {
id = (last + 1) % LIMIT;
}
return (last = id) + workerId * LIMIT;
}
}