IDEA 注解开发流程

IDEA 注解开发流程  分为以下四步  分别是

1 导入依赖

2 配置文件 applicationContext.xml

3 在需要创建对象的类上添加注解

4  测试

详细步骤和代码如下

1 导入依赖

　   <properties>

        <maven.compiler.source>1.9</maven.compiler.source>
        <maven.compiler.target>1.9</maven.compiler.target>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>5.0.2.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
        </dependency>
    </dependencies>

​ 2 配置文件 applicationContext.xml

<?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.xsd">
<!--开启注解  定义扫描包 context:component-scn
   context  名称空间   引入约束
   base-package指定要扫描的包   扫描本包和其子包
-->
    <context:component-scan base-package="cn.kgc"></context:component-scan>
</beans>

​3 在需要创建对象的类上添加注解

package cn.kgc.service.impl;
​
import cn.kgc.dao.UserDao;
import cn.kgc.service.UserService;
import org.springframework.stereotype.Service;
​
import javax.annotation.Resource;
​
/**
 * @author lijun
 * @date 2019/7/4 9:00
 */
@Service
public class UserServiceImpl implements UserService {
    @Resource()
    UserDao userDao;
    public void print() {
       userDao.print();
    }
}
​

​ 4 测试

package cn.kgc;
​
import cn.kgc.service.UserService;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
​
/**
2 * @author lijun
 * @date 2019/7/4 9:03
 */
public class TestAnn {
    @Test
    public void test() {
        //  创建容器
       ApplicationContext ac =  new ClassPathXmlApplicationContext("applicationContext.xml");
        UserService userService = ac.getBean(UserService.class);
        // 获取对象
        userService.print();
    }
}
​

总结注解