MyBatisPlus介绍入门以及项目集成MyBatisPlus

矫情吗；* 2023-08-17 17:08 164阅读 0赞

## 简介 ##

MybatisPlus是一个MyBatis的增强工具包，只做增强不做改变。

为简化开发工作、提高生产效率而生。

## 实现 ##

新建数据库mp,新建表Employee  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQwMjQxOTU3_size_16_color_FFFFFF_t_70]  
插入数据  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQwMjQxOTU3_size_16_color_FFFFFF_t_70 1]  
新建一个maven项目，打开pom.xml引入项目依赖

注意：  
Mybatis以及Mybatis-Spring整合的依赖不要加入到项目配置中，以免引起版本冲突，因为Mybatis-Plus依赖里面全部包括了，会自动维护。

<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>com.badao.mp</groupId>
      <artifactId>hellomp</artifactId>
      <version>0.0.1-SNAPSHOT</version>
      <dependencies>
        
      <dependency>
          <groupId>com.baomidou</groupId>
          <artifactId>mybatis-plus</artifactId>
          <version>2.3</version>
      </dependency>  
      
      <dependency>
       <groupId>junit</groupId>
       <artifactId>junit</artifactId>
       <version>4.9</version>
      </dependency>
      
      <dependency>
       <groupId>log4j</groupId>
       <artifactId>log4j</artifactId>
       <version>1.2.17</version>
      </dependency>
      
      <dependency>
       <groupId>com.mchange</groupId>
       <artifactId>c3p0</artifactId>
       <version>0.9.5.2</version>
      </dependency>
      
      <dependency>
       <groupId>mysql</groupId>
       <artifactId>mysql-connector-java</artifactId>
       <version>8.0.11</version>
      </dependency>
      
      <dependency>
       <groupId>org.springframework</groupId>
       <artifactId>spring-context</artifactId>
       <version>4.3.10.RELEASE</version>
      </dependency>
      <dependency>
       <groupId>org.springframework</groupId>
       <artifactId>spring-orm</artifactId>
       <version>4.3.10.RELEASE</version>
      </dependency>
     
      </dependencies>
    </project>

新建实体类如下：

package com.badao.beans;
     
    public class Employee { 
     
     private Integer id;
     private String name;
     private String email;
     private Integer gender;
     private Integer age;
     public Integer getId() { 
      return id;
     }
     public void setId(Integer id) { 
      this.id = id;
     }
     public String getName() { 
      return name;
     }
     public void setName(String name) { 
      this.name = name;
     }
     public String getEmail() { 
      return email;
     }
     public void setEmail(String email) { 
      this.email = email;
     }
     public Integer getGender() { 
      return gender;
     }
     public void setGender(Integer gender) { 
      this.gender = gender;
     }
     public Integer getAge() { 
      return age;
     }
     public void setAge(Integer age) { 
      this.age = age;
     }
     
    }

新建配置文件  
![在这里插入图片描述][20190930142835910.png]

然后新建db.ptoperties文件，在该文件里面写上下面的内容：

jdbc.driver=com.mysql.jdbc.Driver
    jdbc.url=jdbc:mysql://localhost:3306/mp
    jdbc.username=root
    jdbc.password= 123

log4j.xml代码：

<?xml version="1.0" encoding="UTF-8" ?>
    <!DOCTYPE log4j:configuration SYSTEM "log4j.dtd">
     
    <log4j:configuration xmlns:log4j="http://jakarta.apache.org/log4j/">
     
     <appender name="STDOUT" class="org.apache.log4j.ConsoleAppender">
       <param name="Encoding" value="UTF-8" />
       <layout class="org.apache.log4j.PatternLayout">
        <param name="ConversionPattern" value="%-5p %d{MM-dd HH:mm:ss,SSS} %m (%F:%L) \n" />
       </layout>
     </appender>
     <logger name="java.sql">
       <level value="debug" />
     </logger>
     <logger name="org.apache.ibatis">
       <level value="info" />
     </logger>
     <root>
       <level value="debug" />
       <appender-ref ref="STDOUT" />
     </root>
    </log4j:configuration>

mybatis-config.xml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>
     
    </configuration>

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" xmlns:tx="http://www.springframework.org/schema/tx" xmlns:mybatis-spring="http://mybatis.org/schema/mybatis-spring" xsi:schemaLocation="http://mybatis.org/schema/mybatis-spring http://mybatis.org/schema/mybatis-spring-1.2.xsd 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 http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.0.xsd">
     
     
     
     <context:property-placeholder location="classpath:db.properties"/>
     <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
      <property name="driverClass" value="${jdbc.driver}"></property>
      <property name="jdbcUrl" value="${jdbc.url}"></property>
      <property name="user" value="${jdbc.username}"></property>
      <property name="password" value="${jdbc.password}"></property>
     </bean>
     
     
     <bean id="dataSourceTransactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
      <property name="dataSource" ref="dataSource"></property>
     </bean>
     
     <tx:annotation-driven transaction-manager="dataSourceTransactionManager"/>
     
     
     
     <bean id="sqlSessionFactoryBean" class="org.mybatis.spring.SqlSessionFactoryBean">
      
      <property name="dataSource" ref="dataSource"></property>
      <property name="configLocation" value="classpath:mybatis-config.xml"></property>
      
      <property name="typeAliasesPackage" value="com.badao.beans"></property>  
      
      
     </bean>
     
     
     <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
      <property name="basePackage" value="com.badao.mapper"></property>
     </bean>
     
    </beans>

进行测试：

在src/test/java下新建Junit Test Case  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQwMjQxOTU3_size_16_color_FFFFFF_t_70 2]  
编写代码如下，记得导包不要导错。

package com.badao.test;
    import java.sql.Connection;
     
    import javax.sql.DataSource;
     
    import org.junit.Test;
    import org.springframework.context.ApplicationContext;
     
    import org.springframework.context.support.ClassPathXmlApplicationContext;
     
     
     
     
    public class TestMp { 
     
     private ApplicationContext ioc = new ClassPathXmlApplicationContext("applicationContext.xml");
     
     @Test
     public void testDataSource() throws Exception{ 
      DataSource ds = ioc.getBean("dataSource",DataSource.class);
      System.out.println("******************************************"+ds);
      Connection connection = ds.getConnection();
      System.out.println("******************************************"+connection);
      
     }
     
    }

运行测试效果：  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQwMjQxOTU3_size_16_color_FFFFFF_t_70 3]  
至此测试成功说明环境搭建成功。

集成MybatisPlus

我们只需要把Mybatis自带的SessionFactoryBean替换为MybatisPlus自带的MybatisSqlSessionFactoryBean即可。

打开applicationContext.xml  
找到  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQwMjQxOTU3_size_16_color_FFFFFF_t_70 4]

<bean id="sqlSessionFactoryBean" class="com.baomidou.mybatisplus.spring.MybatisSqlSessionFactoryBean">
      
      <property name="dataSource" ref="dataSource"></property>
      <property name="configLocation" value="classpath:mybatis-config.xml"></property>
      
      <property name="typeAliasesPackage" value="com.badao.beans"></property>   
     </bean>

本文转载自;https://blog.csdn.net/BADAO\_LIUMANG\_QIZHI/article/details/89385833

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