Java Singleton mode

The Java singleton pattern implements the attribute of only one instance of a class.

Implementation mode: A hungry man type is very simple not elaborated. Below is a description of the lazy type.

1. Constructor privatization
2. The static method obtains the instance, the method inside double-check-locking checks. Synchronization methods are not recommended.

public class Singleton {    private static Singleton Singleton;    Private Singleton () {} public    static Singleton getinstance () {        if (Singleton = = null) {//            try {//                Thread.Sleep (+),//            } catch (Interruptedexception e) {//                e.printstacktrace ();/            }            synchronized (singleton.class) {                if (Singleton = = null) {                    Singleton = new Singleton ();}}        }        return singleton;}    }

The code above is intended to make the single-mode failure more likely when there are no synchronized blocks and two checks. The test code will not be written.

Java Singleton mode