spring Bean的三种配置方式

spring Bean的三种配置方式 - StoneGeek - 博客园

正文

Spring Bean有三种配置方式：

• 传统的XML配置方式
• 基于注解的配置
• 基于类的Java Config

添加spring的maven repository

      org.springframework
      spring-core
      
      4.1.0.RELEASE
    
    
      org.springframework
      spring-context
      
      4.1.0.RELEASE
    
    
      org.springframework
      spring-test
      
      4.1.0.RELEASE
    
    
      org.springframework
      spring-tx
      
      4.1.0.RELEASE
    
    
      org.springframework
      spring-beans
      
      4.1.0.RELEASE
    
    
      org.springframework
      spring-jdbc
      
      4.1.0.RELEASE
    
    
      junit
      junit
      4.12
    

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　　BeanFactory.java

package com.stonegeek.service;


public interface BeanFactory {
    public void Beantest();
}

　　BeanFactoryImpl.java

package com.stonegeek.service.impl;

import com.stonegeek.service.BeanFactory;


public class BeanFactroyImpl implements BeanFactory {
    @Override
    public void Beantest() {
        System.out.println("----------------This is a 传统的XML配置的bean!-------------------");
    }
}

　　applicationContext.xml

　　TestBean1.java

package com.stonegeek;

import com.stonegeek.service.BeanFactory;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;


public class TestBean1 {
    @Test
    public void test(){
        ApplicationContext ctx= new ClassPathXmlApplicationContext("applicationContext.xml");
        BeanFactory beanFactory=(BeanFactory) ctx.getBean("beanFactroy");
        beanFactory.Beantest(); //----------------This is a 传统的XML配置的bean!-------------------
    }
}

回到顶部

　　如果一个类使用了@Service，那么此类将自动注册成一个bean，不需要再在applicationContext.xml文件定义bean了，类似的还包括@Component、@Repository、@Controller。

　　然后需要在applicationContext.xml文件中加一行，作用是自动扫描base-package包下的注解：

　　BeanFactoryImpl.java

package com.stonegeek.service.impl;

import com.stonegeek.service.BeanFactory;
import org.springframework.stereotype.Service;


@Service("beanFactory")
public class BeanFactroyImpl implements BeanFactory {
    @Override
    public void Beantest() {
        System.out.println("----------------This is a 基于Java注解的bean!-------------------");
    }
}

　　applicationContext.xml

　　TestBean2.java

package com.stonegeek;

import com.stonegeek.service.BeanFactory;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;


public class TestBean2 {
    @Test
    public void test(){
        ApplicationContext ctx= new ClassPathXmlApplicationContext("applicationContext.xml");
        BeanFactory beanFactory=(BeanFactory) ctx.getBean("beanFactory");
        beanFactory.Beantest();  //This is a 基于java注解的bean！
    }
}

回到顶部

　　通过java类定义spring配置元数据，且直接消除xml配置文件

　　Spring3.0基于java的配置直接支持下面的注解：

　　@Configuration

　　@Bean

　　@DependsOn

　　@Primary

　　@Lazy

　　@import

　　@importResource

　　@Value

　　BeanFactoryImpl.java

package com.stonegeek.service.impl;

import com.stonegeek.service.BeanFactory;


public class BeanFactoryImpl implements BeanFactory {
    @Override
    public void Beantest() {
        System.out.println("----------------This is a 基于类的Java Config的bean!-------------------");
    }
}

　　BeanConfig.java

package com.stonegeek.service.config;


import com.stonegeek.service.BeanFactory;
import com.stonegeek.service.impl.BeanFactoryImpl;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;


@Configuration
public class BeanConfig {
    @Bean
    public BeanFactory beanFactory(){
        return new BeanFactoryImpl();
    }
}

　　TestBean3.java

package com.stonegeek;

import com.stonegeek.service.BeanFactory;
import com.stonegeek.service.config.BeanConfig;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;


public class TestBean3 {
    @Test
    public void test(){
        ApplicationContext applicationContext=new AnnotationConfigApplicationContext(BeanConfig.class);
        BeanFactory beanFactorys=applicationContext.getBean(BeanFactory.class);
        beanFactorys.Beantest();  //This is a 基于类的Java Config Bean！
    }
}

　　以上就是spring bean的三种配置方式的简单介绍！！