使用mybatis核心配置文件和映射文件做的完整项目_记录

本是古典何须时尚 2023-06-24 12:25 27阅读 0赞

记录下使用mybatis查询数据库的实例，此记录用于自己日后回归用。同时，用与于mybatis与spring 结合时，怎么结合配置文件的。

备注：

1、mybatis 有个核心配置文件，用于设置日志、配置数据库信息、简称、注册mapper映射文件等。

2、有个Mapper映射文件，与Dao接口进行对应。

**1、实体类**

public class User {
        private  int id;
        private String username;
        private  int password;
        private  int age;
        private  String sex;
    
        public int getId() {
            return id;
        }
    
        public void setId(int id) {
            this.id = id;
        }
    
        public String getUsername() {
            return username;
        }
    
        public void setUsername(String username) {
            this.username = username;
        }
    
        public int getPassword() {
            return password;
        }
    
        public void setPassword(int password) {
            this.password = password;
        }
    
        public int getAge() {
            return age;
        }
    
        public void setAge(int age) {
            this.age = age;
        }
    
        public String getSex() {
            return sex;
        }
    
        public void setSex(String sex) {
            this.sex = sex;
        }
    
        @Override
        public String toString() {
            return "User{" +
                    "id=" + id +
                    ", username='" + username + '\'' +
                    ", password=" + password +
                    ", age=" + age +
                    ", sex='" + sex + '\'' +
                    '}';
        }
    }

**2、DAO接口**  
public interface UserMapper \{

Object getUserById(int id);  
\}

**3、数据库dbconfig.properties 配置文件：**

jdbcUrl=jdbc:db2://***********
    driverClass=com.ibm.db2.jcc.DB2Driver
    username=********
    password=********

**4、mybatis的核心配置文件**

<?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="dbconfig.properties"></properties>
    <settings>
        
        <setting name="logImpl" value="STDOUT_LOGGING"/>
        
        
    </settings>
        <typeAliases>
            <typeAlias type="com.entity.User" alias="User"/>
            <typeAlias type="com.entity.Book" alias="Book"/>
            <typeAlias type="com.entity.UserHaveMoreBook" alias="UserHaveMoreBook"/>
    
        </typeAliases>
        <environments default="development">
            <environment id="development">
                <transactionManager  type="JDBC"/>
                
                <dataSource type="POOLED">
                    <property name="driver" value="${driverClass}"/>
                    <property name="url" value="${jdbcUrl}"/>
                    <property name="username" value="${user}"/>
                    <property name="password" value="${password}"/>
                </dataSource>
            </environment>
        </environments>
        <mappers>
            <mapper resource="com/Dao/UserMapper.xml"/>
            <mapper resource="com/Dao/UserBookMapper.xml"/>
            <mapper resource="com/Dao/UserHaveMoreBookMapper.xml"/>
    
        </mappers>
    </configuration>

**5、DAO接口对应的Mapper文件：**  
<?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">

<select id="getUserById" parameterType="\_int" resultType="User"> select \* from DB2INST.TBL\_USER Where id = \#\{id\}

</select>

</mapper>

**6、测试**

public class test {
        SqlSession sqlSession;
        UserMapper mapper;
    
        @Before
        public void set(){
             sqlSession = MybatisUtils.getSqlSession();
             mapper = sqlSession.getMapper(UserMapper.class);
     
    
        }
        @Test
        public void findAllTest(){
            User user = mapper.getUserById(30027);
            System.out.printf("结果："+user);
      
        }
     
        @After
        public void end(){
            sqlSession.close();
        }
    }

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