Spring @Configuration的proxyBeanMethods属性的特性

proxyBeanMethods说明

根据注释proxyBeanMethods是为了让使用@Bean注解的方法被代理而实现bean的生命周期的行为。
1.设置为true，那么直接调用方法获取bean，不会创建新的bean，而是会走bean的生命周期的行为。
2.设置为false, 那么直接调用方法获取bean，会创建新的bean，且不会走bean的生命周期的行为。

Configuration 源码

@Target(ElementType.TYPE)
@Retention(RetentionPolicy.RUNTIME)
@Documented
@Component
public @interface Configuration {
        @AliasFor(annotation = Component.class)
        String value() default "";
        boolean proxyBeanMethods() default true;

}

测试验证代码

测试代码

public class AnnotationConfigApplicationContextTest {
    @Test
    public void refresh(){
        AnnotationConfigApplicationContext ctx=new AnnotationConfigApplicationContext();
        ctx.register(AppConfig.class);
        ctx.refresh();
        MyBean myBean=ctx.getBean(MyBean.class);
        myBean.sayHello();
        YourBean yourBean=ctx.getBean(YourBean.class);
        yourBean.sayHello();
    }
}

Configuration代码，设置为false

@Configuration(proxyBeanMethods = false)
public class AppConfig {
    @Bean
    public MyBean myBean(){
        return new MyBean();
    }
    @Bean
    public YourBean yourBean(){
        return new YourBean(myBean());
    }
}

Mybean代码

public class MyBean {
    public MyBean(){
        System.out.println("MyBean construct......");
    }
    @PostConstruct
    public void init(){
         System.out.println("MyBean PostConstruct ....");
    }
    public void sayHello(){
         System.out.println("Hi MyBean ,hello world!");
    }
}

YourBean代码

public class YourBean {
    public MyBean myBean;

   public YourBean(MyBean myBean){
       System.out.println("YourBean construct...");
       this.myBean=myBean;
   }
    @PostConstruct
    public void init(){
        System.out.println("YourBean PostConstruct...");
    }
    public void sayHello(){
        System.out.println("Hi YourBean ,hello world!");
    }
}

执行refresh测试测试代码结果（proxyBeanMethods = false）

MyBean construct......打印了两次，说明被new了两次

10:04:56.066 [main] DEBUG org.springframework.beans.factory.support.DefaultListableBeanFactory - Creating shared instance of singleton bean 'myBean'
MyBean construct......
MyBean PostConstruct ....
10:04:56.069 [main] DEBUG org.springframework.beans.factory.support.DefaultListableBeanFactory - Creating shared instance of singleton bean 'yourBean'
MyBean construct......
YourBean construct...
YourBean PostConstruct...
Hi MyBean ,hello world!
Hi YourBean ,hello world!

执行refresh测试测试代码结果（proxyBeanMethods = true）

MyBean construct......只打印了一次，说明只被new了一次。

10:06:51.727 [main] DEBUG org.springframework.beans.factory.support.DefaultListableBeanFactory - Creating shared instance of singleton bean 'myBean'
MyBean construct......
MyBean PostConstruct ....
10:06:51.741 [main] DEBUG org.springframework.beans.factory.support.DefaultListableBeanFactory - Creating shared instance of singleton bean 'yourBean'
YourBean construct...
YourBean PostConstruct...
Hi MyBean ,hello world!
Hi YourBean ,hello world!