Mybatis实现增删改查

水深无声 2022-04-10 07:59 339阅读 0赞

### 首先往pom文件中加入配置以获取jar包 ###

<dependency>
                <groupId>junit</groupId>
                <artifactId>junit</artifactId>
                <version>4.11</version>
                <scope>test</scope>
            </dependency>
    
            
            <dependency>
                <groupId>org.mybatis</groupId>
                <artifactId>mybatis</artifactId>
                <version>3.4.6</version>
            </dependency>
            
            <dependency>
                <groupId>mysql</groupId>
                <artifactId>mysql-connector-java</artifactId>
                <version>5.1.47</version>
            </dependency>

### 编写一个Mybatis的主配置文件 ###

<?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>
        
        <environments default="development">
            <environment id="development">
                
                <transactionManager type="JDBC"/>
                
                <dataSource type="POOLED">
                    
                    <property name="driver" value="com.mysql.jdbc.Driver"/>
                    
                    <property name="url" value="jdbc:mysql://localhost:3306/mybatis?characterEncoding=UTF-8"/>
                    
                    <property name="username" value="root"/>
                    
                    <property name="password" value="root"/>
                </dataSource>
            </environment>
        </environments>
        <mappers>
            
            <mapper resource="com/hw/entity/Student.xml"/>
        </mappers>
    </configuration>

### 创建实体类和实体类的配置文件 ###

package com.hw.entity;
    
    /**
     * @program: Maven
     * @description:
     * @author: hw
     * @create: 2019-01-01 00:42
     **/
    public class Student {
        private Integer sid;
        private String sname;
        private Integer tid;
    
        public Student() {
            super();
        }
    
        public Student(String sname, Integer tid) {
            this.sname = sname;
            this.tid = tid;
        }
    
        public Student(Integer sid, String sname, Integer tid) {
            this.sid = sid;
            this.sname = sname;
            this.tid = tid;
        }
    
        @Override
        public String toString() {
            return "Student{" +
                    "sid=" + sid +
                    ", sname='" + sname + '\'' +
                    ", tid=" + tid +
                    '}';
        }
    
        public Integer getSid() {
            return sid;
        }
    
        public void setSid(Integer sid) {
            this.sid = sid;
        }
    
        public String getSname() {
            return sname;
        }
    
        public void setSname(String sname) {
            this.sname = sname;
        }
    
        public Integer getTid() {
            return tid;
        }
    
        public void setTid(Integer tid) {
            this.tid = tid;
        }
    }

<?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="student">
        
        
        <select id="findStudentById" resultType="com.hw.entity.Student" parameterType="int">
            select * from student where sid=#{id}
        </select>
    
    
        
        
        <select id="findStudentByName" parameterType="String" resultType="com.hw.entity.Student">
            select * from student where sname like '%${value}%'
        </select>
    
    
        
        
        <insert id="addStudent" parameterType="com.hw.entity.Student">
            insert  into student (sname,tid)
            values (#{sname},#{tid});
        </insert>
    
    
        
        <delete id="delStudent" parameterType="int">
          delete from student where sid =#{id}
    
        </delete>
    
        
        <update id="editStudent" parameterType="com.hw.entity.Student">
          update student set sname=#{sname},tid=#{tid} where sid =#{sid};
        </update>
    
    </mapper>

## 测试: ##

package com.hw.test;
    
    import com.hw.entity.Student;
    
    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.List;
    
    /**
     * @program: Maven
     * @description:
     * @author: hw
     * @create: 2019-01-01 01:12
     **/
    public class Demo1 {
        InputStream inputStream;
    
        SqlSessionFactory build;
    
        SqlSession sqlSession;
    
        @Before
        public void before() {
            try {
                //读取配置文件
                inputStream = Resources.getResourceAsStream("Mybatis.xml");
                //通过sqlsessionFactoryBuilder创建sqlsessionFactory会话工厂
                build = new SqlSessionFactoryBuilder().build(inputStream);
                //通过sqlsessionFactory创建sqlsession
                sqlSession = build.openSession();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    
        @After
        public void after() {
            //关闭sqlsession
            sqlSession.commit();
            sqlSession.close();
        }
    
        /**
         * @Description: 查询
         * @Param: []
         * @return: void
         * @Author: hw
         * @Date: 2019/1/1
         */
        @Test
        public void test1() throws IOException {
            //调用sqlsession的操作数据库的方法
    //        Student student=sqlSession.selectOne("findStudentById",1);
            List<Student> findStudentByName = sqlSession.selectList("findStudentByName", "1");
            findStudentByName.forEach(x -> System.out.println(x));
            //关闭sqlsession
            sqlSession.close();
    
        }
    
    
        /**
         * @Description: 添加
         * @Param: []
         * @return: void
         * @Author: hw
         * @Date: 2019/1/1
         */
        @Test
        public void test2() {
            Student student = new Student("猴子", 1);
            int addStudent = sqlSession.insert("addStudent", student);
            System.out.println(addStudent);
        }
    
        /**
         * @Description: 删除
         * @Param: []
         * @return: void
         * @Author: hw
         * @Date: 2019/1/1
         */
        @Test
        public void test3() {
            System.out.println(sqlSession.delete("delStudent", 2));
        }
    
        /**
         * @Description: 修改
         * @Param:
         * @return:
         * @Author: hw
         * @Date: 2019/1/1
         */
        @Test
        public void test4(){
            Student student=new Student(1,"李箐",2);
            System.out.println(sqlSession.update("editStudent",student));
        }
    
    }

# 结果   ![20190101013025928.png][] #

[20190101013025928.png]: /images/20220401/adae0eca995343bc9ef58a385f792f6c.png