展开
拓展 关闭
邮箱 邮箱
图床 图床
笔记 笔记
ProcessOn ProcessOn
原型图 原型图
CodePen CodePen
服务器 服务器
coding coding
fastmock fastmock
Docker Hub Docker Hub
Travis Cl Travis Cl
码工具 码工具
在线工具 在线工具
蛙蛙工具 蛙蛙工具
PDF24 Tools PDF24 Tools
校招 校招
BOSS直聘 BOSS直聘
猎聘 猎聘
职友集 职友集
天眼查 天眼查
百度 百度
知乎 知乎
简书 简书
抖音 抖音
今日头条 今日头条
统计分析 统计分析
思维导图 思维导图
日历热力图 日历热力图
关系图 关系图
矩形树图 旭日图
订阅号推广码
GitHub
视频
公告栏 关闭

spring5入门（十）：基于注解管理bean，注入属性

  • @Autowired：根据属性类型进行自动装配
# bean.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">
 
    <context:component-scan base-package="com.ychen"></context:component-scan>
 
</beans>
 
# 持久层接口
public interface UserDao {
 
    public void add();
 
}
 
# 持久层实现
@Repository
public class UserDaoImpl implements UserDao {
 
    @Override
    public void add() {
        System.out.println("dao add.....");
    }
 
}
 
# 业务层
@Service
public class UserService {
 
    @Autowired
    private UserDao userDao;
 
    public void add() {
        System.out.println("service add.......");
        userDao.add();
    }
 
}
 
# 测试方法
public class Test3 {
 
    @Test
    public void testAdd() {
        ApplicationContext context = new ClassPathXmlApplicationContext("bean7.xml");
        UserService userService = context.getBean("userService", UserService.class);
        System.out.println(userService);
        userService.add();
    }
 
}
 
# 控制台
com.ychen.spring.ser.UserService@37911f88
service add.......
dao add.....
 
Process finished with exit code 0
  • @Qualifier：根据名称进行注入，需配合@Autowired一起使用
# bean.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">
 
    <context:component-scan base-package="com.ychen"></context:component-scan>
 
</beans>
 
# 持久层接口
public interface UserDao {
 
    public void add();
 
}
 
# 持久层实现
@Repository(value = "userDaoImpl1")
public class UserDaoImpl implements UserDao {
 
    @Override
    public void add() {
        System.out.println("dao add.....");
    }
 
}
 
# 业务层
@Service
public class UserService {
 
    @Autowired
    @Qualifier(value = "userDaoImpl1")
    private UserDao userDao;
 
    public void add() {
        System.out.println("service add.......");
        userDao.add();
    }
 
}
 
# 测试方法
public class Test3 {
 
    @Test
    public void testAdd() {
        ApplicationContext context = new ClassPathXmlApplicationContext("bean7.xml");
        UserService userService = context.getBean("userService", UserService.class);
        System.out.println(userService);
        userService.add();
    }
 
}
 
# 控制台
com.ychen.spring.ser.UserService@37911f88
service add.......
dao add.....
 
Process finished with exit code 0
  • @Resource：可以根据类型注入，可以根据名称注入，该注解并不时spring提供的注解，只是java扩展包中的注解
## 测试一：根据类型注入
# bean.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">
 
    <context:component-scan base-package="com.ychen"></context:component-scan>
 
</beans>
 
# 持久层接口
public interface UserDao {
 
    public void add();
 
}
 
# 持久层实现
@Repository(value = "userDaoImpl1")
public class UserDaoImpl implements UserDao {
 
    @Override
    public void add() {
        System.out.println("dao add.....");
    }
 
}
 
# 业务层
@Service
public class UserService {
 
    @Resource
    private UserDao userDao;
 
    public void add() {
        System.out.println("service add.......");
        userDao.add();
    }
 
}
 
# 测试方法
public class Test3 {
 
    @Test
    public void testAdd() {
        ApplicationContext context = new ClassPathXmlApplicationContext("bean7.xml");
        UserService userService = context.getBean("userService", UserService.class);
        System.out.println(userService);
        userService.add();
    }
 
}
 
# 控制台
com.ychen.spring.ser.UserService@37911f88
service add.......
dao add.....
 
Process finished with exit code 0
 
## 测试二：根据名称注入
# bean.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">
 
    <context:component-scan base-package="com.ychen"></context:component-scan>
 
</beans>
 
# 持久层接口
public interface UserDao {
 
    public void add();
 
}
 
# 持久层实现
@Repository(value = "userDaoImpl1")
public class UserDaoImpl implements UserDao {
 
    @Override
    public void add() {
        System.out.println("dao add.....");
    }
 
}
 
# 业务层
@Service
public class UserService {
 
    @Resource(name = "userDaoImpl1")
    private UserDao userDao;
 
    public void add() {
        System.out.println("service add.......");
        userDao.add();
    }
 
}
 
# 测试方法
public class Test3 {
 
    @Test
    public void testAdd() {
        ApplicationContext context = new ClassPathXmlApplicationContext("bean7.xml");
        UserService userService = context.getBean("userService", UserService.class);
        System.out.println(userService);
        userService.add();
    }
 
}
 
# 控制台
com.ychen.spring.ser.UserService@37911f88
service add.......
dao add.....
 
Process finished with exit code 0
  • @Value：注入普通类型属性
# bean.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">
 
    <context:component-scan base-package="com.ychen"></context:component-scan>
 
</beans>
 
# 持久层接口
public interface UserDao {
 
    public void add();
 
}
 
# 持久层实现类
@Repository
public class UserDaoImpl implements UserDao {
 
    @Override
    public void add() {
        System.out.println("dao add.....");
    }
 
}
 
# 业务层
@Service
public class UserService {
 
    @Value(value = "abc")
    private String name;
 
    @Autowired
    private UserDao userDao;
 
    public void add() {
        System.out.println("service add......." + name);
        userDao.add();
    }
 
}
 
# 测试方法
public class Test3 {
 
    @Test
    public void testAdd() {
        ApplicationContext context = new ClassPathXmlApplicationContext("bean7.xml");
        UserService userService = context.getBean("userService", UserService.class);
        System.out.println(userService);
        userService.add();
    }
 
}
 
# 控制层
com.ychen.spring.ser.UserService@2cb2fc20
service add.......abc
dao add.....
 
Process finished with exit code 0
  • 纯注解开发
# 编写配置类
@Configuration
@ComponentScan(basePackages = {"com.ychen"})
public class SpringConfig {
 
}
 
# 编写测试方法
    @Test
    public void testService2() {
        ApplicationContext context
                = new AnnotationConfigApplicationContext(SpringConfig.class);
        UserService userService = context.getBean("userService", UserService.class);
        System.out.println(userService);
        userService.add();
    }
 
# 控制台
com.ychen.spring.ser.UserService@7975d1d8
service add.......abc
dao add.....
 
Process finished with exit code 0
posted @   DogLeftover  阅读(33)  评论(0)  编辑  收藏  举报
相关博文：
·  spring5入门（九）：基于注解管理bean，创建对象
·  spring5入门（四）：基于xml配置管理bean，注入特殊字符、外部bean、内部bean、级联bean
·  Spring6-IoC（learning）
·  Spring IOC
·  Spring理解1 ioc
阅读排行：
· 阿里巴巴 QwQ-32B真的超越了 DeepSeek R-1吗？
· 10年+ .NET Coder 心语 ── 封装的思维：从隐藏、稳定开始理解其本质意义
· 【设计模式】告别冗长if-else语句：使用策略模式优化代码结构
· 字符编码：从基础到乱码解决
· 提示词工程——AI应用必不可少的技术
点击右上角即可分享
微信分享提示
AI IDE Trae