java-Single-Case mode

One, Singleton mode: A commonly used software design mode. The singleton mode ensures that the class with the pattern can have only one instance of the class that is used in the system. That is, a class has only one instance of an object

Second, application: thread pool, cache, log Object, dialog box, printer, video card driver object is often designed as a singleton

Three, the characteristics of single-case mode:
1, the Singleton class can have only one instance.
2, the Singleton class must create its own unique instance.
3. The Singleton class must provide this instance to all other objects.

Iv. creation of the simple interest model

 Public classSINGLETN {PrivateString name; PrivateString ID; //Create a unique instance    Private StaticSingletn SINGLETN =NewSingletn (); //providing examples to outsiders     Public Staticsingletn getinstant () {returnSingletn; }    //Constructor Privatization    PrivateSingletn () {} Public voidsetName (String name) { This. Name =name; }     Public voidsetId (String id) { This. ID =ID; }     PublicString GetName () {returnname; }     PublicString getId () {returnID; }}

a hungry man single-case mode

 Public classSINGLETN {PrivateString name; PrivateString ID; //Create a unique instance    Private StaticSINGLETN Singletn; //providing examples to outsiders     Public Staticsingletn getinstant () {if(Singletn = =NULL){//double check            synchronized(SINGLETN.class){//Thread -safety issues, locking for thread synchronization when multi-threadingsingletn=NewSingletn (); }        }        returnSingletn; }    //Constructor Privatization    PrivateSingletn () {} Public voidsetName (String name) { This. Name =name; }     Public voidsetId (String id) { This. ID =ID; }     PublicString GetName () {returnname; }     PublicString getId () {returnID; }}

Lazy Single-case mode

A hungry man and lazy-type difference:

1. A hungry man is the static initialization method, which is the object that the class is loaded on, so the system resources should be used in advance.

2. Lazy type similar to lazy loading, in use when the instantiation, multi-threaded thread security issues, need double check

It is recommended to use a hungry man style.

java-Single-Case mode