[转] Spring Bean工厂创建Bean实例的方法之使用静态工厂类

定义接口：

package  Bean.staticFactoryBean;

public   interface  Axe  {
   public String chop();
}


package  Bean.staticFactoryBean;

public   interface  Person  {
   public void useAxe();
}

 实现类：

package  Bean.staticFactoryBean;

public   class  AmericanPerson  implements  Person  {
    private Axe axe;
    public Axe getAxe() {
        return axe;
    }
    public void setAxe(Axe axe) {
        this.axe = axe;
    }
    
    public void useAxe() {
        System.out.println(axe.chop());
        
    }

}


package  Bean.staticFactoryBean;

public   class  ChinesePerson  implements  Person  {
    private Axe axe;
    public Axe getAxe() {
        return axe;
    }
    public void setAxe(Axe axe) {
        this.axe = axe;
    }
    
    public void useAxe() {
        System.out.println(axe.chop());
        
    }

}

package  Bean.staticFactoryBean;

public   class  SteelAxe  implements  Axe  {

    public String chop() {
        return "这是一把铁斧子";

    }

}
package  Bean.staticFactoryBean;

public   class  WoodAxe  implements  Axe  {

    public String chop() {
        return "这是一把木头斧子";

    }

}

工厂类：

package  Bean.staticFactoryBean;
import  Bean.staticFactoryBean. * ;
public   class  BeingFactory  {
    
   public static Person getPerson(String arg){
       if(arg.equalsIgnoreCase("chinese")){
           return new Bean.staticFactoryBean.ChinesePerson();
       }
       else{
           return new Bean.staticFactoryBean.AmericanPerson();
       }
   }
}

配置文件，和使用构造函数创建bean不同的是，这里的class是静态方法的实现类，多加了factory-method属性，工厂方法的参数通过<constructor-arg>定义

<? xml version="1.0" encoding="UTF-8" ?>
<! DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN//EN" "http://www.springframework.org/dtd/spring-beans.dtd" >

< beans >

   < bean  id ="chinese"  class ="Bean.staticFactoryBean.BeingFactory"  factory-method ="getPerson" >
     < constructor-arg >
       < value > chinese </ value >
     </ constructor-arg >
     < property  name ="axe" >
       < ref  local ="woodaxe" />
     </ property >
   </ bean >
  
    < bean  id ="american"  class ="Bean.staticFactoryBean.BeingFactory"  factory-method ="getPerson" >
     < constructor-arg >
       < value > american </ value >
     </ constructor-arg >
     < property  name ="axe" >
       < ref  local ="steelaxe" />
     </ property >
   </ bean >
   < bean  id ="woodaxe"  class ="Bean.staticFactoryBean.WoodAxe" ></ bean >
   < bean  id ="steelaxe"  class ="Bean.staticFactoryBean.SteelAxe" ></ bean >
</ beans >

测试代码：

public   static   void  main(String[] args)  throws  Exception  {
        
        String path=new Test().getClass().getResource("/").getPath();
        String realpath=path.substring(1, path.length());
        ApplicationContext context=new FileSystemXmlApplicationContext(realpath+"/staticMethodbeans.xml");
        
        
        Person person1=(Person)context.getBean("chinese");
        person1.useAxe();
        Person person2=(Person)context.getBean("american");
        person2.useAxe();
       
    }

 

From: http://blog.csdn.net/daryl715/article/details/1539011