Spring使用教程（三）注解1

1:@component:基本注解，标识了一个受Spring管理的主键

2:@respository:标识持久层主键

3:@Service:标识服务层（业务层）主键

4:@Controller:标识表示层主键

•Spring 有默认的命名策略: 使用非限定类名, 第一个字母小写. 也可以在注解中通过 value 属性值标识组件的名称

使用注解，需要在Spring的配置文件中声明：<context:component-scan>

–base-package 属性指定一个需要扫描的基类包，Spring 容器将会扫描这个基类包里及其子包中的所有类.

–当需要扫描多个包时, 可以使用逗号分隔.

如果仅希望扫描特定的类而非基包下的所有类，可使用 resource-pattern 属性过滤特定的类

–<context:include-filter> 子节点表示要包含的目标类  需要在<context:component-scan>配置use-default-filters="false"

–<context:exclude-filter> 子节点表示要排除在外的目标类

–<context:component-scan> 下可以拥有若干个 <context:include-filter> 和 <context:exclude-filter> 子节点

<?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:context="http://www.springframework.org/schema/context"
    xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsd">
        <!-- 指定Spring IOC容器扫描的包 -->
        <!-- resource-pattern  扫描指定的资源 -->
        <!--  <context:component-scan base-package="com.test.spring.annotation"
            resource-pattern="controller/*.class"
        ></context:component-scan>-->

        <!-- exclude-filter 子节点指定排除那些指定表达式的组件 -->
        <!-- include-filter 子节点包含那些表达式的组件,需要配置 use-default-filters为false-->
        <context:component-scan base-package="com.test.spring.annotation" use-default-filters="false">
        <!--
            <context:exclude-filter type="annotation" expression="org.springframework.stereotype.Controller"/>
            <context:include-filter type="annotation" expression="org.springframework.stereotype.Controller"/>
             -->
             <!-- -
             <context:exclude-filter type="assignable" expression="com.test.spring.annotation.TestObject"/>
             -->
             <context:include-filter type="assignable" expression="com.test.spring.annotation.TestObject"/>
        </context:component-scan>
</beans>

package com.test.spring.annotation;

import org.springframework.stereotype.Component;

@Component
public class TestObject {

}

package com.test.spring.annotation.controller;

import org.springframework.stereotype.Controller;

@Controller
public class UserController {
    public void execute(){
        System.out.println("usercontroller");

    }
}

package com.test.spring.annotation.repository;

public interface UserRepository {
    public void save();
}

package com.test.spring.annotation.repository;

import org.springframework.stereotype.Repository;
//注解可以通过value属性值标识，bean在IOC容器中的name
@Repository("userRepository")
public class UserRepositoryImlpl implements UserRepository{

    public void save() {
        System.out.println("实现接口的save");
    }

}

package com.test.spring.annotation.service;

import org.springframework.stereotype.Service;

@Service
public class UserService {
    public void add(){
        System.out.println("USERSERVICE的 add");
    }
}

package com.test.spring.annotation;

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

import com.test.spring.annotation.controller.UserController;
import com.test.spring.annotation.repository.UserRepository;
import com.test.spring.annotation.repository.UserRepositoryImlpl;
import com.test.spring.annotation.service.UserService;

public class Main {
    public static void main(String[] args) {
        ApplicationContext con=new ClassPathXmlApplicationContext("beans_annocation.xml");
        TestObject to=(TestObject) con.getBean("testObject");
        System.out.println(to);

        UserService ser=(UserService) con.getBean("userService");
        System.out.println(ser);

        UserController ucon=(UserController) con.getBean("userController");
        System.out.println(ucon);

        UserRepositoryImlpl ur=(UserRepositoryImlpl) con.getBean("userRepository");
        System.out.println(ur);

    }
}