目录
一、传统的XML配置方式
二、基于java注解的配置
三、基于类的Java Config
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
一、传统的XML配置方式
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
xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:context="http://www.springframework.org/schema/context" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd "> 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!------------------- } } 二、基于java注解的配置 使用组件扫描可以不必在Spring的配置文件中配置各个` `base-package`表示需要扫描的“根包”,当配置后，Spring容器会自动扫描根包下所有类，及各及子包类。 目的：让Spring知道有哪些类，事实上，只是配置组件扫描，Spring并不会创建这些类的对象。如需要Spring创建某些类的对象，还需要为这些类添加注解！ 常用类注解： @Component---------通用注解(推荐) @Named-------------通用注解(不推荐) @Service-----------业务逻辑类注解 @Controller--------控制器类注解 @Repository--------持久层(数据访问层)处理类注解 >以上5种注解是等效的！只是语义不同！（推荐采用对应的） 当同时配置组件扫描和注解后，Spring就会创建这些对象！ Spring创建类的对象时，默认使用bean的id是将类的首字母改为小写： class：Userao---->bean id：userDao 如果需要自定义名称，可以在注解上添加配置： @Component("dao") 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 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:context="http://www.springframework.org/schema/context" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd "> 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！ } } 三、基于类的Java Config 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！！