Spring的三种注入方式：

Type1接口注入：
public class ClassA{

private InterfaceB classB;

public doSomething(){

Object obj = Class.forName(Config.BImplementation).newInstance();

classB = (InterfaceB)ojb;

classB.doIt();

}
}

Type2setter注入：

setter:
public class RequestAction{

private String message;

public void setMessage(String msg){

this.message = msg;

}

public String getMessage(){

return message;

}

public void method(String str){

Syso(getMessage()+str);

}
}

applicationContext.xml:
<bean id = "theAction" class="xxx.xxx.RequestAction">

<property name = "message">

<value>Hello</value>

</property>
</bean>

Test.java:
@Test
public void test(){

ApplicationContext context = new ClassPathApplicationContext("xxx/ApplicationContext.xml");
RequestAction action = (RequestAction)context.getBean("theAction");
Syso(action.method("World!"));
}

Type3构造注入：
public class DIByCondstructor{

private final DataSource dataSource;

private final String message;

public DIByConstructor(DataSource ds,String msg){

this.dataSource = ds;

this.message = msg;

}
}