Three ways to implement spring Dependency injection (DI)

Spring relies on injection (DI) in three ways, respectively:

1. Interface Injection

2. Setter Method Injection

3. Construct Method Injection

<?xml:namespace prefix = o ns = "Urn:schemas-microsoft-com:office:office"/>

Here's how these three dependency injections are implemented in spring.

First we need the following classes:

Interface Logic.java

Interface Implementation Class Logicimpl.java

A processing class Loginaction.java

There is also a test class Testmain.java

Logic.java as follows:

Package com.spring.test.di;

Public Interface Logic {

Public String GetName ();

}

Logicimpl.java as follows:

Package com.spring.test.di;

Public class Logicimpl implements logic{

Public String GetName () {

return "Fengyun";

}

}

Testmain.java

Package com.spring.test.di;

Import Org.springframework.context.ApplicationContext;

Import Org.springframework.context.support.FileSystemXmlApplicationContext;

public class Testmain {

/**

* @param args

*/

public static void Main (string[] args) {

Get ApplicationContext Object

ApplicationContext CTX = new Filesystemxmlapplicationcontext (

"Applicationcontext.xml");

Get Bean

Loginaction loginaction = (loginaction) ctx.getbean ("Loginaction");

Loginaction.execute ();

}

}

Loginaction.java will vary slightly depending on the injection method used

The following method is injected to see the Loginaction.java class

Setter Method Injection:

Package com.spring.test.di;

Public class loginaction {

Private Logic logic;

Public void Execute () {

String name = Logic.getname ();

System.out.print ("My name is" + name);

}

/**

* @return The logic

*/

Public Logic Getlogic () {

return logic;

}

/**

* @param logic

* The logic to set

*/

Public void setlogic (logic logic) {

this. Logic = logic;

}

}