Mybatis配置文件详解

迷南。 2022-02-15 08:45 343阅读 0赞

**一、目录结构**  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3poYW5nMTUwMTE0_size_16_color_FFFFFF_t_70]

**二、代码详解**

1.maven核心配置文件

<?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>com.mollen.mybatis</groupId>
        <artifactId>mybatis</artifactId>
        <version>1.0-SNAPSHOT</version>
    
        <dependencies>
        
            <dependency>
                <groupId>org.mybatis</groupId>
                <artifactId>mybatis</artifactId>
                <version>3.4.5</version>
            </dependency>
            
            <dependency>
                <groupId>mysql</groupId>
                <artifactId>mysql-connector-java</artifactId>
                <version>5.1.38</version>
            </dependency>
            
            <dependency>
                <groupId>log4j</groupId>
                <artifactId>log4j</artifactId>
                <version>1.2.17</version>
            </dependency>
            
            <dependency>
                <groupId>junit</groupId>
                <artifactId>junit</artifactId>
                <version>4.11</version>
            </dependency>
            
        </dependencies>
    
        
        <build>
            
            <resources>
                <resource>
                    <directory>src/main/java</directory>
                    <includes>
                        <include>**/*.xml</include>
                    </includes>
                </resource>
            </resources>
            
    	
            <plugins>
           	    
                <plugin>
                    <groupId>org.apache.maven.plugins</groupId>
                    <artifactId>maven-compiler-plugin</artifactId>
                    <configuration>
                        <source>1.8</source>
                        <target>1.8</target>
                        <encoding>utf-8</encoding>
                    </configuration>
                </plugin>
            </plugins>
        </build>
    
    </project>

2.mybatis核心配置文件：SqlMapConfig.xml

<?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>
    
        
        <properties resource="db.properties"></properties>
        
        
        <typeAliases>
            <package name="com.mollen.dao"/>
            <package name="com.mollen.bean"/>
        </typeAliases>
    
        
        <environments default="mysql">
            <environment id="mysql">
                <transactionManager type="JDBC"></transactionManager>
                <dataSource type="POOLED">
                    <property name="driver" value="${jdbc.driver}"></property>
                    <property name="url" value="${jdbc.url}"></property>
                    <property name="username" value="${jdbc.username}"></property>
                    <property name="password" value="${jdbc.password}"></property>
                </dataSource>
            </environment>
        </environments>
    
        
        <mappers>
         	
            
            
            
            <package name="com.mollen.dao"/> 
        </mappers>
    
    </configuration>

3.配置数据源文件

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

4.映射文件配置：UserDao.xml

<?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.mollen.dao.UserDao">
    
        
        <resultMap id="userMap" type="user">
            
            <id property="id" column="id"></id>
            
            <result property="username" column="username"></result>
            <result property="birthday" column="birthday"></result>
            <result property="sex" column="sex"></result>
            <result property="address" column="address"></result>
    
        </resultMap>
    
        
        <select id="findAll" resultType="user">
            SELECT * FROM  user;
        </select>
    
        
        <select id="findUserById" resultMap="userMap">
            SELECT * FROM user WHERE id in
            <foreach collection="array" open="(" close=")" separator="," item="uid">
                #{uid}
            </foreach>
        </select>
    
        
        <select id="findByName"  resultMap="userMap">
            select * from user where username like #{name}
        </select>
    
        
        <select id="findByCondition"  resultMap="userMap">
            SELECT * FROM user WHERE 1=1
            <if test="username != null">
                AND username like #{username}
            </if>
            <if test="sex != null">
                AND sex like #{sex}
            </if>
        </select>
    
        
        <insert id="saveOne">
            INSERT  INTO
              user
            VALUES
            (
              null,
              #{username},
              #{birthday},
              #{sex},
              #{address}
            )
        </insert>
    
        
        <delete id="deleteOne" >
            DELETE  FROM
              user
            WHERE
              id = #{id}
        </delete>
    
        
        <update id="updateUser">
            UPDATE
              user
            SET
              username = #{username},
              birthday = #{birthday},
              sex = #{sex},
              address = #{address}
            WHERE
              id = #{id}
        </update>
    
    </mapper>

5.Dao接口类：UserDao.java

package com.mollen.dao;
    
    import com.mollen.bean.User;
    
    import java.util.List;
    
    /**
     * @ClassName: UserDao
     * @Auther: Mollen
     * @CreateTime: 2018-10-27  20:19:07
     * @Description:
     */
    public interface UserDao {
    
        /**
         * 1.查询所有
         * @return
         */
        public List<User> findAll();
    
    
        /**
         * 2.根据id查询用户(动态执行参数)
         * @return
         */
        public List<User> findUserById(Integer...ids);
    
        /**
         * 3.根据用户模糊查询
         */
        public List<User> findByName(String username);
    
        /**
         * 4.根据条件模糊查询
         * @param user
         * @return
         */
        public List<User> findByCondition(User user);
    
        /**
         * 5.添加一条数据
         * @param user
         */
        public void saveOne(User user);
    
        /**
         * 6.删除一条数据
         * @param user
         */
        public void deleteOne(User user);
    
        /**
         * 7.修改用户
         */
        public void updateUser(User user);
    }

6.实体类：User.java

package com.mollen.bean;
    
    import java.util.Date;
    
    /**
     * @ClassName: User
     * @Auther: Mollen
     * @CreateTime: 2018-10-29  10:11:48
     * @Description:
     */
    public class User {
        private int id;
        private String username;
        private Date birthday;
        private String sex;
        private String address;
    	//getter/setter/toString/...
    }

原文：[https://blog.csdn.net/mollen/article/details/84566676][https_blog.csdn.net_mollen_article_details_84566676]

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3poYW5nMTUwMTE0_size_16_color_FFFFFF_t_70]: /images/20220215/58e338e9507742368301fe6fb1fc40af.png
[https_blog.csdn.net_mollen_article_details_84566676]: https://blog.csdn.net/mollen/article/details/84566676