Spring实战——@Autowire注解

布满荆棘的人生 2021-07-24 19:54 383阅读 0赞

**一 配置**

<?xml version="1.0" encoding="GBK"?>
    <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-4.0.xsd
         http://www.springframework.org/schema/context
         http://www.springframework.org/schema/context/spring-context-4.0.xsd">
         <context:component-scan
               base-package="org.crazyit.app.service,org.crazyit.app.dao"/>     
    </beans>

**二 dao接口**

BaseDao

package org.crazyit.app.dao;
    
    public interface BaseDao<T>
    {
         void save(T e);
    }

ItemDao

package org.crazyit.app.dao;
    import org.crazyit.app.domain.*;
    
    public interface ItemDao extends BaseDao<Item>
    {
    }

UserDao

package org.crazyit.app.dao;
    import org.crazyit.app.domain.*;
    
    public interface UserDao extends BaseDao<User>
    {
    }

**三 dao实现类**

BaseDaoImpl

package org.crazyit.app.dao.impl;
    import org.crazyit.app.dao.*;
    
    public class BaseDaoImpl<T> implements BaseDao<T>
    {
         public void save(T e)
         {
               System.out.println("程序保存对象：" + e);
         }
    }

ItemDaoImpl

package org.crazyit.app.dao.impl;
    
    
    import org.springframework.stereotype.*;
    
    
    import org.crazyit.app.dao.*;
    import org.crazyit.app.domain.*;
    
    @Component("itemDao")
    public class ItemDaoImpl extends BaseDaoImpl<Item>
        implements ItemDao
    {
    }

UserDaoImpl

package org.crazyit.app.dao.impl;
    
    
    import org.springframework.stereotype.*;
    
    
    import org.crazyit.app.dao.*;
    import org.crazyit.app.domain.*;
    
    @Component("userDao")
    public class UserDaoImpl extends BaseDaoImpl<User>
        implements UserDao
    {
    }

**四 Bean**

Item

package org.crazyit.app.domain;
    
    public class Item
    {
    }

User

package org.crazyit.app.domain;
    
    public class User
    {
    }

**五 service接口**

BaseService

package org.crazyit.app.service;
    
    
    import org.springframework.stereotype.*;
    import org.springframework.beans.factory.annotation.*;
    
    
    import org.crazyit.app.service.*;
    
    public interface BaseService<T>
    {
        void addEntity(T entity);
    }

ItemService

package org.crazyit.app.service;
    
    
    import org.springframework.stereotype.*;
    import org.springframework.beans.factory.annotation.*;
    
    
    import org.crazyit.app.service.*;
    import org.crazyit.app.domain.*;
    
    @Component
    public interface ItemService extends BaseService<Item>
    {
    
    
    }

UserService

package org.crazyit.app.service;
    
    
    import org.springframework.stereotype.*;
    import org.springframework.beans.factory.annotation.*;
    
    
    import org.crazyit.app.service.*;
    import org.crazyit.app.domain.*;
    
    @Component
    public interface UserService extends BaseService<User>
    {
    }

**六 Service实现类**

BaseServiceImpl

package org.crazyit.app.service.impl;
    
    
    import org.springframework.stereotype.*;
    import org.springframework.beans.factory.annotation.*;
    
    
    import org.crazyit.app.dao.*;
    import org.crazyit.app.service.*;
    
    public class BaseServiceImpl<T> implements BaseService<T>
    {
        @Autowired
        private BaseDao<T> dao;
        public void addEntity(T entity)
        {
            System.out.println("调用" + dao
                + "保存实体：" + entity);
        }
    }

ItemServiceImpl

package org.crazyit.app.service.impl;
    
    
    import org.springframework.stereotype.*;
    import org.springframework.beans.factory.annotation.*;
    
    
    import org.crazyit.app.service.*;
    import org.crazyit.app.domain.*;
    
    @Component("itemService")
    public class ItemServiceImpl extends BaseServiceImpl<Item>
        implements ItemService
    {
    }

UserServiceImpl

package org.crazyit.app.service.impl;
    
    
    import org.springframework.stereotype.*;
    import org.springframework.beans.factory.annotation.*;
    
    
    import org.crazyit.app.service.*;
    import org.crazyit.app.domain.*;
    
    @Component("userService")
    public class UserServiceImpl extends BaseServiceImpl<User>
        implements UserService
    {
    }

**七 测试类**

package lee;
    
    
    import org.springframework.context.ApplicationContext;
    import org.springframework.context.support.ClassPathXmlApplicationContext;
    
    
    import org.crazyit.app.service.*;
    import org.crazyit.app.domain.*;
    
    public class BeanTest
    {
        public static void main(String[] args)throws Exception
        {
            // 创建Spring容器
            ApplicationContext ctx = new
                ClassPathXmlApplicationContext("beans.xml");
            UserService us = ctx.getBean("userService", UserService.class);
            us.addEntity(new User());
            ItemService is = ctx.getBean("itemService", ItemService.class);
            is.addEntity(new Item());
        }
    }

**八 测试**

调用org.crazyit.app.dao.impl.UserDaoImpl@b7dd107保存实体：org.crazyit.app.domain.User@42eca56e调用org.crazyit.app.dao.impl.ItemDaoImpl@52f759d7保存实体：org.crazyit.app.domain.Item@7cbd213e