使用@Configuration_@Bean_@Import简化xml配置

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使用@Configuration_@Bean_@Import简化xml配置

首先建一个Maven项目，导入项目所需要的spring依赖如下：

<dependencies>
	<!--spring context -->
	<dependency>
		<groupId>org.springframework</groupId>
		<artifactId>spring-context</artifactId>
		<version>4.1.1.RELEASE</version>
	</dependency>

	<!--spring core -->
	<dependency>
		<groupId>org.springframework</groupId>
		<artifactId>spring-core</artifactId>
		<version>4.1.1.RELEASE</version>
	</dependency>

	<!--spring bean -->
	<dependency>
		<groupId>org.springframework</groupId>
		<artifactId>spring-beans</artifactId>
		<version>4.1.1.RELEASE</version>
	</dependency>

	<!--spring aop -->

	<dependency>
		<groupId>org.springframework</groupId>
		<artifactId>spring-aop</artifactId>
		<version>4.1.1.RELEASE</version>
	</dependency>

	<!--spring jdbc -->
	<dependency>
		<groupId>org.springframework</groupId>
		<artifactId>spring-jdbc</artifactId>
		<version>4.1.1.RELEASE</version>
	</dependency>

	<!-- spring tx -->
	<dependency>
		<groupId>org.springframework</groupId>
		<artifactId>spring-tx</artifactId>
		<version>4.1.1.RELEASE</version>
	</dependency>

	<dependency>
		<groupId>org.springframework.batch</groupId>
		<artifactId>spring-batch-core</artifactId>
		<version>3.0.2.RELEASE</version>
	</dependency>

	<dependency>
		<groupId>junit</groupId>
		<artifactId>junit</artifactId>
		<version>4.10</version>
		<scope>test</scope>
	</dependency>

	<dependency>
		<groupId>cglib</groupId>
		<artifactId>cglib</artifactId>
		<version>3.1</version>
	</dependency>
</dependencies>

新建UserService，RoleService两个类，如下：

package com.lyx;

public class UserService {
	public void addUser() {
		System.out.println("add user");
	}
}

package com.lyx;

public class RoleService {
	public void addRole() {
		System.out.println("add role");
	}
}

使用@Configuration注解

如下：

package com.lyx;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

@Configuration
public class ServiceConfig {

	@Bean(name = "roleService")
	public RoleService getRoleService() {
		return new RoleService();
	}

	@Bean(name = "userService")
	public UserService getUserService() {
		return new UserService();
	}
}

使用@Import注解

如下：

package com.lyx;

import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Import;

@Configuration
@Import(ServiceConfig.class)
public class AppConfig2 {
	
}

运行该项目

App.java如下，使用AnnotationConfigApplicationContext类加载项目

package com.lyx;

import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;

public class App {

	public static void main(String argss[]) {
		@SuppressWarnings("resource")
		ApplicationContext context = new AnnotationConfigApplicationContext(
				AppConfig2.class);
		RoleService roleService = (RoleService) context.getBean("roleService");
		roleService.addRole();

		UserService userService = (UserService) context.getBean("userService");
		userService.addUser();
	}

}

运行结果：

add role

add user

使用XML的方式配置上面的例子

spring-service.xml配置service，如下：

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:aop="http://www.springframework.org/schema/aop"
	xmlns:context="http://www.springframework.org/schema/context"
	xmlns:cache="http://www.springframework.org/schema/cache"
	xsi:schemaLocation="http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd
		http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
		http://www.springframework.org/schema/cache http://www.springframework.org/schema/cache/spring-cache.xsd
		http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd">

	<bean id="roleService" class="com.lyx.RoleService"></bean>
	<bean id="userService" class="com.lyx.UserService"></bean>
</beans>

applicationContext.xml配置app，如下：

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:aop="http://www.springframework.org/schema/aop"
	xmlns:context="http://www.springframework.org/schema/context"
	xmlns:cache="http://www.springframework.org/schema/cache"
	xsi:schemaLocation="http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd
		http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
		http://www.springframework.org/schema/cache http://www.springframework.org/schema/cache/spring-cache.xsd
		http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd">

	<import resource="spring-service.xml" />
</beans>

App2.java如下

package com.lyx;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

public class App2 {
	public static void main(String args[]) {
		@SuppressWarnings("resource")
		ApplicationContext context = new ClassPathXmlApplicationContext(
				"applicationContext.xml");
		RoleService roleService = (RoleService) context.getBean("roleService");
		roleService.addRole();
		UserService userService = (UserService) context.getBean("userService");
		userService.addUser();

	}
}

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转载于:https://my.oschina.net/xinxingegeya/blog/339334