详解Spring中的FactoryBean

package com.myapp.core.factorybean; 
 
public class Car { 
 private String make; 
 private int year; 
  public String getMake() { 
    return make; 
  } 
  public void setMake(String make) { 
    this.make = make; 
  } 
  public int getYear() { 
    return year; 
  } 
  public void setYear(int year) { 
    this.year = year; 
  } 
    
}

package com.myapp.core.factorybean; 
 
import org.springframework.beans.factory.FactoryBean; 
 
public class MyCarFactoryBean implements FactoryBean<Car>{ 
   
  private String make; 
   
  private int year; 
 
  public void setMake(String make) { 
    this.make = make; 
  } 
 
  public void setYear(int year) { 
    this.year = year; 
  } 
 
  @Override 
  public Car getObject() throws Exception { 
    // TODO Auto-generated method stub 
     
    //Here is a complex car object created 
     // wouldn't be a very useful FactoryBean 
    // if we could simply instantiate the object! 
    Car car = new Car(); 
     
    if(year != 0){ 
      car.setYear(this.year); 
    } 
     
    if("make".equals(make)){ 
      car.setMake("we are making bla bla bla"); 
    }else{ 
      car.setMake(this.make); 
    } 
     
    return car; 
  } 
 
  @Override 
  public Class<?> getObjectType() { 
    // TODO Auto-generated method stub 
    return Car.class; 
  } 
 
  @Override 
  public boolean isSingleton() { 
    // TODO Auto-generated method stub 
    return false; 
  } 
 
} 

package com.myapp.core.factorybean; 
 
public class Person { 
  
  private Car car; 
 
  public Car getCar() { 
    return car; 
  } 
 
  public void setCar(Car car) { 
    this.car = car; 
  } 
   
  public String toString(){ 
     
    return car.getMake()+"::::"+car.getYear(); 
  } 
} 

<bean id="car" class="com.myapp.core.factorybean.MyCarFactoryBean"> 
  <property name="make" value="makeing car"/> 
  <property name="year" value="123"/> 
</bean> 
 
<bean id="person" class="com.myapp.core.factorybean.Person"> 
 
<property name="car" ref="car"/> 
 
</bean> 

package com.myapp.core.factorybean; 
 
import org.springframework.context.ApplicationContext; 
import org.springframework.context.support.ClassPathXmlApplicationContext; 
 
public class MainTest { 
 public static void main(String[] args) { 
   
   ApplicationContext context = new ClassPathXmlApplicationContext("resource/others.xml"); 
    
 Person person =  (Person)context.getBean("person"); 
    
   // Car car =  (Car)context.getBean("car"); 
    
  // System.out.println(car); 
  System.out.println(person); 
} 
}