Mybatis的CRUD操作【包含查询记录总条数、模糊查找】（完整代码演示）

╰+攻爆jí腚メ 2022-10-29 05:25 108阅读 0赞

### Mybatis的CRUD操作 ###

*  目录结构
 *  完整代码

# 目录结构 #

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80Mzg4MzkxNw_size_16_color_FFFFFF_t_70]

# 完整代码 #

**pom.xml：**

<?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.keafmd</groupId>
        <artifactId>day02_eesy_01mybatisCRUD</artifactId>
        <version>1.0-SNAPSHOT</version>
        <packaging>jar</packaging>
    
        <dependencies>
            <dependency>
                <groupId>org.mybatis</groupId>
                <artifactId>mybatis</artifactId>
                <version>3.5.5</version>
            </dependency>
            <dependency>
                <groupId>mysql</groupId>
                <artifactId>mysql-connector-java</artifactId>
                <version>5.1.49</version>
            </dependency>
            <dependency>
                <groupId>log4j</groupId>
                <artifactId>log4j</artifactId>
                <version>1.2.17</version>
            </dependency>
            <dependency>
                <groupId>junit</groupId>
                <artifactId>junit</artifactId>
                <version>4.13</version>
                <scope>test</scope>
            </dependency>
        </dependencies>
    
    
    </project>

**log4j.properties：**

# Set root category priority to INFO and its only appender to CONSOLE.
    #log4j.rootCategory=INFO, CONSOLE            debug   info   warn error fatal
    log4j.rootCategory=debug, CONSOLE, LOGFILE
    
    # Set the enterprise logger category to FATAL and its only appender to CONSOLE.
    log4j.logger.org.apache.axis.enterprise=FATAL, CONSOLE
    
    # CONSOLE is set to be a ConsoleAppender using a PatternLayout.
    log4j.appender.CONSOLE=org.apache.log4j.ConsoleAppender
    log4j.appender.CONSOLE.layout=org.apache.log4j.PatternLayout
    log4j.appender.CONSOLE.layout.ConversionPattern=%d{ ISO8601} %-6r [%15.15t] %-5p %30.30c %x - %m\n
    
    # LOGFILE is set to be a File appender using a PatternLayout.
    log4j.appender.LOGFILE=org.apache.log4j.FileAppender
    log4j.appender.LOGFILE.File=d:\axis.log
    log4j.appender.LOGFILE.Append=true
    log4j.appender.LOGFILE.layout=org.apache.log4j.PatternLayout
    log4j.appender.LOGFILE.layout.ConversionPattern=%d{ ISO8601} %-6r [%15.15t] %-5p %30.30c %x - %m\n

**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>
        
        <environments default="mysql">
            
            <environment id="mysql">
                
                <transactionManager type="JDBC"></transactionManager>
                
                <dataSource type="POOLED">
                    
                    <property name="driver" value="com.mysql.jdbc.Driver"/>
                    <property name="url" value="jdbc:mysql://localhost:3306/eesy_mybatis"/>
                    <property name="username" value="root"/>
                    <property name="password" value="18044229"/>
                </dataSource>
            </environment>
        </environments>
    
        
        <mappers>
            <mapper resource="com/keafmd/dao/IUserDao.xml"></mapper>
            
        </mappers>
    
    
    </configuration>

**User：**

package com.keafmd.domain;
    
    import java.io.Serializable;
    import java.util.Date;
    
    /** * Keafmd * * @ClassName: User * @Description: * @author: 牛哄哄的柯南 * @date: 2021-02-08 15:16 */
    public class User implements Serializable { 
        private Integer id;
        private String username;
        private Date birthday;
        private String sex;
        private String address;
    
        public Integer getId() { 
            return id;
        }
    
        public void setId(Integer id) { 
            this.id = id;
        }
    
        public String getUsername() { 
            return username;
        }
    
        public void setUsername(String username) { 
            this.username = username;
        }
    
        public Date getBirthday() { 
            return birthday;
        }
    
        public void setBirthday(Date birthday) { 
            this.birthday = birthday;
        }
    
        public String getSex() { 
            return sex;
        }
    
        public void setSex(String sex) { 
            this.sex = sex;
        }
    
        public String getAddress() { 
            return address;
        }
    
        public void setAddress(String address) { 
            this.address = address;
        }
    
        @Override
        public String toString() { 
            return "User{" +
                    "id=" + id +
                    ", username='" + username + '\'' +
                    ", birthday=" + birthday +
                    ", sex='" + sex + '\'' +
                    ", address='" + address + '\'' +
                    '}';
        }
    }

**IUserDao：**

package com.keafmd.dao;
    
    import com.keafmd.domain.User;
    import org.apache.ibatis.annotations.Select;
    
    import java.util.List;
    
    /** * Keafmd * * @ClassName: IUserDao * @Description: 用户的持久层接口 * @author: 牛哄哄的柯南 * @date: 2021-02-06 19:29 */
    
    public interface IUserDao { 
        /** * 查询所有操作 * @return */
        List<User> findAll();
    
        /** * 保存用户 * @param user */
        void saveUser(User user);
    
        /** * 更新用户 * @param user */
        void updateUser(User user);
    
        /** * 根据id删除用户 * @param id */
        void deleteUser(Integer id);
    
        /** * 根据id查新用户信息 * @param id * @return */
        User findById(Integer id);
    
        /** * 根据名称模糊查询 * @param username * @return */
        List<User> findByName(String username);
    
        /** * 查询总用户数 * @return */
        int findTotal();
    
    }

**IUserDao.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.keafmd.dao.IUserDao">
        
        
        <select id="findAll" resultType="com.keafmd.domain.User">
            select * from user
        </select>
    
        
        <insert id="saveUser" parameterType="com.keafmd.domain.User">
            
            <selectKey keyProperty="id" keyColumn="id" resultType="int" order="AFTER">
                select last_insert_id();
            </selectKey>
            insert into user(username,address,sex,birthday)values(#{ username},#{ address},#{ sex},#{ birthday});
        </insert>
    
        
        <update id="updateUser" parameterType="com.keafmd.domain.User">
            update user set username=#{ username},address=#{ address},sex=#{ sex},birthday=#{ birthday} where id=#{ id}
        </update>
    
        
        
        <delete id="deleteUser" parameterType="Integer">
            delete from user where id = #{ uid}
        </delete>
    
        
        <select id="findById" parameterType="Integer" resultType="com.keafmd.domain.User">
            select * from user where id = #{ id}
        </select>
    
        
        <select id="findByName" parameterType="String" resultType="com.keafmd.domain.User">
            
            
            select * from user where username like '%${value}%'
        </select>
    
        
        <select id="findTotal" resultType="int">
            select count(id) from user;
        </select>
    
    </mapper>

**测试代码：**

package com.keafmd.test;
    
    import com.keafmd.dao.IUserDao;
    import com.keafmd.domain.User;
    import org.apache.ibatis.io.Resources;
    import org.apache.ibatis.session.SqlSession;
    import org.apache.ibatis.session.SqlSessionFactory;
    import org.apache.ibatis.session.SqlSessionFactoryBuilder;
    import org.junit.After;
    import org.junit.Before;
    import org.junit.Test;
    
    import java.io.IOException;
    import java.io.InputStream;
    import java.util.Date;
    import java.util.List;
    
    /** * Keafmd * * @ClassName: MybatisTest * @Description: 测试类，测试crud操作 * @author: 牛哄哄的柯南 * @date: 2021-02-08 15:24 */
    public class MybatisTest { 
    
        private InputStream in;
        private SqlSession sqlsession;
        private IUserDao userDao;
    
        @Before // 用于在测试方法执行前执行
        public void init()throws Exception{ 
            //1.读取配置文件,生成字节输入流
            in = Resources.getResourceAsStream("SqlMapConfig.xml");
            //2.创建SqlSessionFactory工厂
            SqlSessionFactoryBuilder builder = new SqlSessionFactoryBuilder();
            SqlSessionFactory factory = builder.build(in);
            //3.使用工厂生产SqlSession对象
            sqlsession = factory.openSession();
            //4.使用SqlSession创建Dao接口的代理对象
            userDao = sqlsession.getMapper(IUserDao.class);
        }
    
        @After // 用于在测试方法执行后执行
        public void destory() throws Exception{ 
            //提交事务
            sqlsession.commit();
            //6.释放资源
            sqlsession.close();
            in.close();
        }
    
        /** * 查询所有 * @throws Exception */
        @Test
        public void testFindAll() throws Exception { 
    
            //5.使用代理对象执行方法
            List<User> users = userDao.findAll();
            for (User user : users) { 
                System.out.println(user);
            }
    
        }
    
        /** * 测试保存操作 */
        @Test
        public void testSave() throws Exception { 
            User user = new User();
            user.setUsername("Keafmd laset insertid");
            user.setSex("男");
            user.setBirthday(new Date());
            user.setAddress("XXXXXXX");
            System.out.println("保存操作前："+user);
            //5.执行保存方法
            userDao.saveUser(user);
            System.out.println("保存操作后："+user);
        }
    
        /** * 测试更新 * @throws Exception */
        @Test
        public void testUpdate() throws Exception { 
            User user = new User();
            user.setId(42);
            user.setUsername("update");
            user.setSex("男");
            user.setBirthday(new Date());
            user.setAddress("XXXXXXX");
            //5.执行更新方法
            userDao.updateUser(user);
        }
    
        /** * 测试删除 * @throws Exception */
        @Test
        public void testDelete() throws Exception { 
            //5.执行删除方法
            userDao.deleteUser(48);
        }
    
        /** * 查询一个 * @throws Exception */
        @Test
        public void testFindOne() throws Exception { 
            //5.执行查询一个方法
            User user = userDao.findById(50);
            System.out.println(user);
        }
    
        /** * 根据username模糊查询 * @throws Exception */
        @Test
        public void testFindByName() throws Exception { 
            //5.执行模糊查询方法
            /*List<User> users = userDao.findByName("%王%");*/
            List<User> users = userDao.findByName("王");
            for (User user : users) { 
                System.out.println(user);
            }
        }
    
        /** * 查询记录总条数 * @throws Exception */
        @Test
        public void testFindTiotal() throws Exception { 
            //5.执行记录总条数
            int total = userDao.findTotal();
            System.out.println(total);
        }
    
    }

> **以上就是Mybatis的CRUD操作【包含查询记录总条数、模糊查找】（完整代码演示）的全部内容。**

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