Java Learning---Generating an in-memory duplicate ID

Idutils.java

Import java.util.random;/** * Various ID generation strategies * <p>Title:IDUtils</p> * <p>description: </p> * @version 1 .0 */public class Idutils {/** * picture name generated */public static String Genimagename () {//Fetch the current time long shaping value contains milliseconds long Millis = system.current Timemillis ();//long Millis = System.nanotime ();//plus three-bit random number randomly random = new random (), int end3 = Random.nextint (999);// If less than three bits in front of 0String str = Millis + String.Format ("%03d", End3); return str;} /** * Product ID generation */public static long Genitemid () {//Take the long shape value of the current time contains milliseconds long Millis = System.currenttimemillis ();//long Millis = Sy Stem.nanotime ();//plus two-bit random number randomly random = new random (), int end2 = Random.nextint (99),//if less than two bits in front of 0String str = Millis + stri Ng.format ("%02d", end2); Long id = new Long (str); return ID;} public static void Main (string[] args) {for (int i=0;i< 100;i++) System.out.println (Genitemid ());}}

Java Learning---Generating an in-memory duplicate ID