javaee spring整合mybatis

案例一

包含dao层

创建maven webapp项目

maven仓库需要改为阿里云

引入依赖

xml 复制代码

<?xml version="1.0" encoding="UTF-8"?>

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>

  <groupId>org.example</groupId>
  <artifactId>testSSM</artifactId>
  <version>1.0-SNAPSHOT</version>
  <packaging>war</packaging>

  <name>testSSM Maven Webapp</name>
  <!-- FIXME change it to the project's website -->
  <url>http://www.example.com</url>

  <properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    <maven.compiler.source>1.7</maven.compiler.source>
    <maven.compiler.target>1.7</maven.compiler.target>
  </properties>

  <dependencies>
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>4.11</version>
      <scope>test</scope>
    </dependency>

    <!-- 1.导入Spring相关的jar包 -->
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-context</artifactId>
      <version>4.3.18.RELEASE</version>
    </dependency>
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-core</artifactId>
      <version>4.3.18.RELEASE</version>
    </dependency>

    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-beans</artifactId>
      <version>4.3.18.RELEASE</version>
    </dependency>
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-context-support</artifactId>
      <version>4.3.18.RELEASE</version>
    </dependency>

    <!-- 导入mybatis的jar包 -->
    <dependency>
      <groupId>mysql</groupId>
      <artifactId>mysql-connector-java</artifactId>
      <version>5.1.37</version>
    </dependency>
    <dependency>
      <groupId>org.mybatis</groupId>
      <artifactId>mybatis</artifactId>
      <version>3.4.6</version>
    </dependency>
    <dependency>
      <groupId>com.mchange</groupId>
      <artifactId>c3p0</artifactId>
      <version>0.9.5.2</version>
    </dependency>

    <!-- 配置日志信息-->
    <dependency>
      <groupId>log4j</groupId>
      <artifactId>log4j</artifactId>
      <version>1.2.17</version>
    </dependency>

    <!-- spring 整合 mybatis-->
    <dependency>
      <groupId>org.mybatis</groupId>
      <artifactId>mybatis-spring</artifactId>
      <version>1.3.0</version>
    </dependency>
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-jdbc</artifactId>
      <version>4.3.18.RELEASE</version>
    </dependency>

  </dependencies>

  <build>
    <resources>
      <resource>
        <!-- 将Mapper的映射文件拷贝出来 -->
        <directory>src/main/java</directory>
        <includes>
          <include>**/*.xml</include>
        </includes>
        <filtering>true</filtering>
      </resource>
    </resources>
    <finalName>testSSM</finalName>
    <pluginManagement><!-- lock down plugins versions to avoid using Maven defaults (may be moved to parent pom) -->
      <plugins>
        <plugin>
          <artifactId>maven-clean-plugin</artifactId>
          <version>3.1.0</version>
        </plugin>
        <!-- see http://maven.apache.org/ref/current/maven-core/default-bindings.html#Plugin_bindings_for_war_packaging -->
        <plugin>
          <artifactId>maven-resources-plugin</artifactId>
          <version>3.0.2</version>
        </plugin>
        <plugin>
          <artifactId>maven-compiler-plugin</artifactId>
          <version>3.8.0</version>
        </plugin>
        <plugin>
          <artifactId>maven-surefire-plugin</artifactId>
          <version>2.22.1</version>
        </plugin>
        <plugin>
          <artifactId>maven-war-plugin</artifactId>
          <version>3.2.2</version>
        </plugin>
        <plugin>
          <artifactId>maven-install-plugin</artifactId>
          <version>2.5.2</version>
        </plugin>
        <plugin>
          <artifactId>maven-deploy-plugin</artifactId>
          <version>2.8.2</version>
        </plugin>
      </plugins>
    </pluginManagement>
  </build>
</project>

spring配置文件

xml 复制代码

<?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"
       xmlns:jdbc="http://www.springframework.org/schema/jdbc"
       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 http://www.springframework.org/schema/jdbc http://www.springframework.org/schema/jdbc/spring-jdbc.xsd">

    <!-- 1.扫描包中的注解 -->
    <context:component-scan base-package="com.test" />

    <!--导入db.properties文件-->
    <context:property-placeholder location="classpath:db.properties" />

    <!--创建了数据源 -->
    <bean id="comboPooledDataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
        <property name="driverClass" value="${driverClass}" />
        <property name="jdbcUrl" value="${url}"/>
        <property name="user" value="${user}" />
        <property name="password" value="${password}" />
    </bean>

    <!--创建SqlSessionFactory对象 -->
    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="dataSource" ref="comboPooledDataSource" />
        <property name="configLocation" value="classpath:sqlMapConfig.xml" />
    </bean>

    <!-- 扫描mapper文件 生成代理对象 替代之前dao层的操作 -->
    <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
         <property name="basePackage" value="com.test.mapper" />
    </bean>

</beans>

数据库信息

xml 复制代码

driverClass=com.mysql.jdbc.Driver
url=jdbc:mysql://localhost:3306/itstar
user=itstar
password=yyy123456

mybatis配置文件

xml 复制代码

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE configuration
        PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>

    <!--配置db.properties  转移到spring中-->
    <!--<properties resource="db.properties" />-->
    <!-- 配置日志管理 -->
    <settings>
        <setting name="logImpl" value="STDOUT_LOGGING"/>
    </settings>

    <!-- 设置别名-->
    <typeAliases>
        <package name="com.test.pojo" />
    </typeAliases>

    <!-- 转移到spring配置文件中 -->
    <!--<environments default="development">-->
        <!--<environment id="development">-->
            <!--<transactionManager type="JDBC"/>-->
            <!--<dataSource type="POOLED">-->
                <!--<property name="driver" value="${driverClass}"/>-->
                <!--<property name="url" value="${url}"/>-->
                <!--<property name="username" value="${user}"/>-->
                <!--<property name="password" value="${password}"/>-->
            <!--</dataSource>-->
        <!--</environment>-->
    <!--</environments>-->

     <!--注册mapper文件 转移到spring中-->
    <!--<mappers>-->
       <!--<package name="com.test.mapper" />-->
    <!--</mappers>-->

</configuration>

dao层

java 复制代码

package com.test.dao;

import com.test.pojo.Items;

import java.util.List;

public interface IItemsDao {

    public List<Items> selectItems();
}

java 复制代码

package com.test.dao.impl;

import com.test.dao.IItemsDao;
import com.test.mapper.ItemsMapper;
import com.test.pojo.Items;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;

import java.util.List;

//实现类
@Component
public class ItemsDao implements IItemsDao {

    @Autowired
    private SqlSessionFactory sqlSessionFactory;

    public SqlSessionFactory getSqlSessionFactory() {
        return sqlSessionFactory;
    }

    public void setSqlSessionFactory(SqlSessionFactory sqlSessionFactory) {
        this.sqlSessionFactory = sqlSessionFactory;
    }

    //转移到Spring的配置文件中  让Spring创建SqlSessionFactory对象
//    public ItemsDao()
//    {
//        InputStream inputStream=this.getClass().getClassLoader().getResourceAsStream("sqlMapConfig.xml");
//
//        SqlSessionFactoryBuilder sqlSessionFactoryBuilder=new SqlSessionFactoryBuilder();
//
//        this.sqlSessionFactory= sqlSessionFactoryBuilder.build(inputStream);
//    }

    //查询所有的商品信息
        @Override
        public List<Items> selectItems() {

        SqlSession sqlSession= sqlSessionFactory.openSession();

        ItemsMapper itemsMapper= sqlSession.getMapper(ItemsMapper.class);

        return itemsMapper.selectItems();

        }
}

mapper

java 复制代码

package com.test.mapper;

import com.test.pojo.Items;

import java.util.List;

//创建一个接口  代理ItemsMapper.xml文件
public interface ItemsMapper {

    public List<Items> selectItems();
}

xml 复制代码

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper
                PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
                "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.test.mapper.ItemsMapper">

    <!-- 查询 -->
    <select id="selectItems" resultType="Items">
        select * from items
    </select>


</mapper>

service层

java 复制代码

package com.test.service;

import com.test.pojo.Items;

import java.util.List;

public interface IItemsService {

    public List<Items> selectItems();
}

java 复制代码

package com.test.service.impl;

import com.test.dao.IItemsDao;
import com.test.pojo.Items;
import com.test.service.IItemsService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.util.List;

//service层的实现类

@Service
public class ItemsService implements IItemsService {

    @Autowired
    private IItemsDao itemsDao;

    public IItemsDao getItemsDao() {
        return itemsDao;
    }

    public void setItemsDao(IItemsDao itemsDao) {
        this.itemsDao = itemsDao;
    }

    @Override
    public List<Items> selectItems() {
        return itemsDao.selectItems();
    }
}

测试类

java 复制代码

package com.test.service;

import com.test.pojo.Items;
import com.test.service.impl.ItemsService;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

import java.util.List;

public class TestItemsService {

    @Test
    public void test()
    {
        //测试service层的查询方法
        ApplicationContext applicationContext=new ClassPathXmlApplicationContext("applicationContext.xml");

        IItemsService itemsService= applicationContext.getBean("itemsService",IItemsService.class);

        List<Items> itemsList= itemsService.selectItems();

        System.out.println(itemsList);
    }
}

案例二

省略dao层，由spring代替

在案例一的基础上，修改spring配置文件

xml 复制代码

<?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"
       xmlns:jdbc="http://www.springframework.org/schema/jdbc"
       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 http://www.springframework.org/schema/jdbc http://www.springframework.org/schema/jdbc/spring-jdbc.xsd">

    <!-- 1.扫描包中的注解 -->
    <context:component-scan base-package="com.test" />

    <!--导入db.properties文件-->
    <context:property-placeholder location="classpath:db.properties" />

    <!--创建了数据源 -->
    <bean id="comboPooledDataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
        <property name="driverClass" value="${driverClass}" />
        <property name="jdbcUrl" value="${url}"/>
        <property name="user" value="${user}" />
        <property name="password" value="${password}" />
    </bean>

    <!--创建SqlSessionFactory对象 -->
    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="dataSource" ref="comboPooledDataSource" />
        <property name="configLocation" value="classpath:sqlMapConfig.xml" />
    </bean>

    <!-- 扫描mapper文件 生成代理对象 替代之前dao层的操作 -->
    <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
         <property name="basePackage" value="com.test.mapper" />
    </bean>

</beans>

删除dao层

修改service层

java 复制代码

package com.test.service.impl;

import com.test.mapper.ItemsMapper;
import com.test.pojo.Items;
import com.test.service.IItemsService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.util.List;

//service层的实现类

@Service
public class ItemsService implements IItemsService {

    //spring会帮我们创建一个代理对象（ 实现了ItemsMapper接口的），代理对象代理的是dao层的功能
    @Autowired
    private ItemsMapper itemsMapper;

    public ItemsMapper getItemsMapper() {
        return itemsMapper;
    }

    public void setItemsMapper(ItemsMapper itemsMapper) {
        this.itemsMapper = itemsMapper;
    }

    @Override
    public List<Items> selectItems() {
        return itemsMapper.selectItems();
    }
}