Guice Learning (ii) constructor injection (Constructor Inject)

To demonstrate the following constructor injection that supports multiple parameters, here I write 2 interfaces and their implementation classes. Notes are written in the program notes.

1. Interface (interface)

/* * Creation : 2015年6月30日 */package com.guice.constructorInject;import com.google.inject.ImplementedBy;@ImplementedBy(ServiceImpl.class)publicinterface Service {    publicvoidexecute();}

/* * Creation : 2015年6月30日 */package com.guice.constructorInject;import com.google.inject.ImplementedBy;@ImplementedBy(HelloGuiceImpl.class)publicinterface HelloGuice {    publicvoidsayHello();}

2. Implementation class (Implementation)

package  Com.guice.constructorInject; public  class  serviceimpl  Span class= "Hljs-keyword" >implements  service  {  @Override  public  void   execute  () {System.out.println ( "Hello Guice, this is field inject demo! ");}}  

package com.guice.constructorInject;import com.google.inject.Singleton;/* * 保证是单例 */@Singletonpublicclass HelloGuiceImpl implements HelloGuice {    @Override    publicvoidsayHello() {        System.out.println("Hello Guice !");    }}

3. Test class

/ * * creation:2015 year June 30 */ PackageCom.guice.constructorInject;ImportCom.google.inject.Guice;ImportCom.google.inject.Inject; Public  class constructorinjectdemo {    PrivateService service;PrivateHelloguice Helloguice; PublicServiceGetService() {returnService } PublicHelloguiceGethelloguice() {returnHelloguice; }/** * Constructor Injection: Benefits: You can guarantee that there is only one place to complete the attribute injection, * you can ensure that some initialization is done in the constructor: the instantiation of the class is bound to the parameter, limiting the way the class is instantiated. */    /* * @Inject * public Constructorinjectdemo (Service service) {* This.service = service; * }     */    / * * Supports multi-parameter constructor injection, but only one constructor must be labeled inject * /    @Inject     Public Constructorinjectdemo(Service service, Helloguice Helloguice) { This. Service = Service; This. Helloguice = Helloguice; } Public Static void Main(string[] args)        {Constructorinjectdemo instance = Guice.createinjector (). getinstance (Constructorinjectdemo.class);        Instance.getservice (). Execute ();    Instance.gethelloguice (). SayHello (); }}

Output Result:

Hello Guice, this is field inject demo!
Hello Guice!

Guice Learning (ii) constructor injection (Constructor Inject)