MyBatis_CURD

一、项目结构

二、代码实现

 package com.jmu.bean;

 public class Student {
   private Integer id;
   private String name;
   private double score;
   private int age;
 public Student() {
     super();
 }

 public Student(String name, int age ,double score) {
     super();
     this.name = name;
     this.score = score;
     this.age = age;
 }

 @Override
 public String toString() {
     return "Student [id=" + id + ", name=" + name + ", score=" + score + ", age=" + 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 double getScore() {
     return score;
 }
 public void setScore(double score) {
     this.score = score;
 }
 public int getAge() {
     return age;
 }
 public void setAge(int age) {
     this.age = age;
 }

 }

 package com.jmu.dao;

 import java.util.List;
 import java.util.Map;

 import com.jmu.bean.Student;

 public interface IStudentDao {
   void insertStudent (Student student);
   void insertStudentCacheId(Student student);//插入后获取

   void deleteStudentById(int id);
   void updateStudent(Student student);

   List<Student> selectAllStudents();//查询所有
   Map<String,Object> selectAllStudentsMap();
    Student selectStudentById(int id);  //根据id查询
    List<Student> selectStudentsByName(String name);//模糊查询
 }
  

 package com.jmu.dao;

 import static org.hamcrest.CoreMatchers.nullValue;

 import java.io.IOException;
 import java.io.InputStream;
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;

 import javax.persistence.MapKey;

 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 com.jmu.bean.Student;
 import com.jmu.utils.MybatisUtils;

 public class StudentDaoImpl implements IStudentDao {

     private InputStream inputStream;
     private SqlSession sqlSession;

     @Override
     public void insertStudent(Student student) {
         // TODO Auto-generated method stub
         try {
             /*
              * // 1、加载主配置文件 inputStream =
              * Resources.getResourceAsStream("mybatis-config.xml"); //
              * 2、创建SqlSessionFactory对象 SqlSessionFactory sqlSessionFactory = new
              * SqlSessionFactoryBuilder().build(inputStream); sqlSession =
              * sqlSessionFactory.openSession(); // 4、相关操作
              */
             sqlSession = MybatisUtils.getSqlSession();
             sqlSession.insert("insertStudent", student);
             sqlSession.commit();
         } finally {

             if (sqlSession != null) {
                 sqlSession.close();
             }
         }
     }

     @Override
     public void insertStudentCacheId(Student student) {
         // TODO Auto-generated method stub
         try {

             sqlSession = MybatisUtils.getSqlSession();
             sqlSession.insert("insertStudentCacheId", student);
             sqlSession.commit();
         } finally {

             if (sqlSession != null) {
                 sqlSession.close();
             }
         }
     }

     @Override
     public void deleteStudentById(int id) {
         // TODO Auto-generated method stub
         try {

             sqlSession = MybatisUtils.getSqlSession();
             sqlSession.update("deleteStudentById", id);
             sqlSession.commit();
         } finally {

             if (sqlSession != null) {
                 sqlSession.close();
             }
         }
     }

     @Override
     public void updateStudent(Student student) {
         // TODO Auto-generated method stub
         try {

             sqlSession = MybatisUtils.getSqlSession();
             sqlSession.update("updateStudent", student);
             sqlSession.commit();
         } finally {

             if (sqlSession != null) {
                 sqlSession.close();
             }
         }
     }

     @Override
     public List<Student> selectAllStudents() {
         // TODO Auto-generated method stub
         List<Student> students =new ArrayList<Student>();
         try {
             sqlSession=MybatisUtils.getSqlSession();
             students=sqlSession.selectList("selectAllStudents");

         } finally {
             if (sqlSession!=null) {
                 sqlSession.close();

             }
         }

         return students;
     }

     @Override
     public Map<String, Object> selectAllStudentsMap() {
         // TODO Auto-generated method stub
         Map<String, Object> map=new HashMap<>();
         try {
             sqlSession=MybatisUtils.getSqlSession();
             map=sqlSession.selectMap("selectAllStudents", "name");
         } finally {
             // TODO: handle finally clause
             if (sqlSession!=null) {
                 sqlSession.close();
             }
         }
         return map;
     }

     @Override
     public Student selectStudentById(int id) {
         // TODO Auto-generated method stub
         Student student=null;
         try {
             sqlSession=MybatisUtils.getSqlSession();
             student=sqlSession.selectOne("selectStudentById", id);

         } finally {
             // TODO: handle finally clause
             if (sqlSession!=null) {
                 sqlSession.close();

             }
         }
         return student;
     }

     @Override
     public List<Student> selectStudentsByName(String name) {
         // TODO Auto-generated method stub
         List<Student> students =new ArrayList<Student>();
         try {
             sqlSession=MybatisUtils.getSqlSession();
             students=sqlSession.selectList("selectStudentByName",name);

         } finally {
             if (sqlSession!=null) {
                 sqlSession.close();

             }
         }
         return students;
     }

 }

<?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.jmu.dao">
<insert id="insertStudent" parameterType="Student">
insert into
student(name,age,score) values(#{name},#{age},#{score})
</insert>

<insert id="insertStudentCacheId">
insert into student(name,age,score) values(#{name},#{age},#{score})
<selectKey resultType="int" keyProperty="id" order="AFTER">
select @@identity
</selectKey>
</insert>
<delete id="deleteStudentById">
delete from student where id=#{XXX}<!--这里的#{} 仅仅是个占位符，里边放什么都行 -->
</delete>
<update id="updateStudent">
update student set name=#{name},age=#{age},score=#{score} where id=#{id}
</update>
<select id="selectAllStudents" resultType="Student">
select id,name,age,score from student
</select>
<select id="selectStudentById" resultType="Student">
select id,name,age,score from student where id=#{JJJ}
</select>
<select id="selectStudentByName" resultType="Student">
<!-- select id,name,age,score from student where name like CONCAT('%',#{XXX},'%') -->
<!-- select id,name,age,score from student where name like '%王二%' -->
<!-- select id,name,age,score from student where name like '%${value}%' --><!-- 不存在sql注入 风险，但是效率低 -->
select id,name,age,score from student where name like '%' #{XXX} '%'<!--常用 -->

</select>
</mapper>

 package com.jmu.utils;

 import java.io.IOException;
 import java.io.InputStream;

 import org.apache.ibatis.io.Resources;
 import org.apache.ibatis.session.SqlSession;
 import org.apache.ibatis.session.SqlSessionFactory;
 import org.apache.ibatis.session.SqlSessionFactoryBuilder;

 public class MybatisUtils {
     private static SqlSessionFactory sqlSessionFactory;

     public static SqlSession getSqlSession() {

         try {
             InputStream is = Resources.getResourceAsStream("mybatis-config.xml");
             if (sqlSessionFactory == null) {
                 sqlSessionFactory = new SqlSessionFactoryBuilder().build(is);

             }
             return sqlSessionFactory.openSession();
         } catch (IOException e) {
             // TODO Auto-generated catch block
             e.printStackTrace();
         }

         return null;

     }
 }

 jdbc.driver=com.mysql.jdbc.Driver
 jdbc.url=jdbc:mysql://127.0.0.1:3306/test
 jdbc.username=root
 jdbc.password=123456

 <?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="jdbc_mysql.properties"> </properties>
 <typeAliases >
   <package name="com.jmu.bean"   />
 </typeAliases>
 <!--配置运行环境  -->
     <environments default="development">
         <environment id="development">
             <transactionManager type="JDBC" />
             <dataSource type="POOLED">
                 <property name="driver" value="${jdbc.driver}" />
                 <property name="url"
                     value="${jdbc.url}" />
                 <property name="username" value="${jdbc.username}" />
                 <property name="password" value="${jdbc.password}" />
             </dataSource>
         </environment>
     </environments>
     <!--注册映射文件 -->
     <mappers>
         <mapper resource="com/jmu/dao/mapper.xml" />
     </mappers>
 </configuration>

 package com.jmu.test;

 import static org.junit.Assert.*;

 import java.util.List;
 import java.util.Map;

 import org.junit.Before;
 import org.junit.Test;

 import com.jmu.bean.Student;
 import com.jmu.dao.IStudentDao;
 import com.jmu.dao.StudentDaoImpl;

 public class MyTest {
     private IStudentDao dao;

     @Before
     public void Before() {
         dao = new StudentDaoImpl();
     }

     @Test
     public void test01() {
         Student student = new Student("明明",19,87.9);
         System.out.println("插入前：student="+student);
         dao.insertStudent(student);
         System.out.println("插入后：student="+student);
     }
     //插入后获取
     @Test
     public void test02(){
         Student student =new Student("明明",23,99.5);
         System.out.println("插入前：student="+student);
         dao.insertStudentCacheId(student);
         System.out.println("插入后：student="+student);
     }
     @Test
     public void test03(){
      dao.deleteStudentById(25);
     }
     @Test
     public void test04(){
      Student student=new Student("红酒",23,93.5);
      student.setId(28);
      dao.updateStudent(student);
     }
     @Test
     public void test05(){
      List<Student> students=dao.selectAllStudents();
      for(Student student : students){
          System.out.println(student);
      }
     }
     @Test
     public void test06(){
      Map<String, Object> map = dao.selectAllStudentsMap();
      System.out.println(map.get("王维"));
     }
     @Test
     public void test07(){
      Student student=dao.selectStudentById(33);
      System.out.println(student);
     }
     @Test
     public void test08(){
      List<Student>  students = dao.selectStudentsByName("王二");
       for (Student student : students) {
         System.out.println(student);
     }
     }

 }

插入前：student=Student [id=null, name=明明, score=87.9, age=19]
DEBUG [main] - ==>  Preparing: insert into student(name,age,score) values(?,?,?)
DEBUG [main] - ==> Parameters: 明明(String), 19(Integer), 87.9(Double)
DEBUG [main] - <==    Updates: 1
插入后：student=Student [id=null, name=明明, score=87.9, age=19]
插入前：student=Student [id=null, name=明明, score=99.5, age=23]
DEBUG [main] - ==>  Preparing: insert into student(name,age,score) values(?,?,?)
DEBUG [main] - ==> Parameters: 明明(String), 23(Integer), 99.5(Double)
DEBUG [main] - <==    Updates: 1
DEBUG [main] - ==>  Preparing: select @@identity
DEBUG [main] - ==> Parameters:
DEBUG [main] - <==      Total: 1
插入后：student=Student [id=118, name=明明, score=99.5, age=23]
DEBUG [main] - ==>  Preparing: delete from student where id=?
DEBUG [main] - ==> Parameters: 25(Integer)
DEBUG [main] - <==    Updates: 0
DEBUG [main] - ==>  Preparing: update student set name=?,age=?,score=? where id=?
DEBUG [main] - ==> Parameters: 红酒(String), 23(Integer), 93.5(Double), 28(Integer)
DEBUG [main] - <==    Updates: 1
DEBUG [main] - ==>  Preparing: select id,name,age,score from student
DEBUG [main] - ==> Parameters:
DEBUG [main] - <==      Total: 95
Student [id=17, name=王维, score=93.5, age=23]
Student [id=18, name=王维, score=93.5, age=23]
Student [id=19, name=王维, score=93.5, age=23]
Student [id=20, name=王维, score=93.5, age=23]
Student [id=21, name=王维, score=93.5, age=23]
Student [id=22, name=王维, score=93.5, age=23]
Student [id=23, name=王维, score=93.5, age=23]
Student [id=24, name=王维, score=93.5, age=23]
Student [id=26, name=王维, score=93.5, age=23]
Student [id=27, name=王维, score=93.5, age=23]
Student [id=28, name=红酒, score=93.5, age=23]
Student [id=29, name=安抚王二, score=93.5, age=23]
Student [id=30, name=王维一, score=93.5, age=23]
Student [id=31, name=王维二, score=93.5, age=23]
Student [id=32, name=王二分, score=93.5, age=23]
Student [id=33, name=王二维, score=93.5, age=23]
Student [id=34, name=王问维, score=93.5, age=23]
Student [id=35, name=王维, score=93.5, age=23]
Student [id=36, name=明明, score=87.9, age=19]
Student [id=37, name=明明, score=99.5, age=23]
Student [id=38, name=明明, score=87.9, age=19]
Student [id=39, name=明明, score=99.5, age=23]
Student [id=40, name=明明, score=87.9, age=19]
Student [id=41, name=明明, score=99.5, age=23]
Student [id=42, name=明明, score=87.9, age=19]
Student [id=43, name=明明, score=99.5, age=23]
Student [id=44, name=明明, score=87.9, age=19]
Student [id=45, name=明明, score=99.5, age=23]
Student [id=46, name=明明, score=87.9, age=19]
Student [id=47, name=明明, score=99.5, age=23]
Student [id=48, name=明明, score=87.9, age=19]
Student [id=49, name=明明, score=99.5, age=23]
Student [id=50, name=明明, score=87.9, age=19]
Student [id=51, name=明明, score=99.5, age=23]
Student [id=52, name=明明, score=87.9, age=19]
Student [id=53, name=明明, score=99.5, age=23]
Student [id=54, name=明明, score=87.9, age=19]
Student [id=55, name=明明, score=99.5, age=23]
Student [id=56, name=明明, score=87.9, age=19]
Student [id=57, name=明明, score=99.5, age=23]
Student [id=58, name=明明, score=87.9, age=19]
Student [id=59, name=明明, score=99.5, age=23]
Student [id=60, name=明明, score=87.9, age=19]
Student [id=61, name=明明, score=99.5, age=23]
Student [id=62, name=明明, score=87.9, age=19]
Student [id=63, name=明明, score=99.5, age=23]
Student [id=64, name=明明, score=87.9, age=19]
Student [id=65, name=明明, score=99.5, age=23]
Student [id=66, name=明明, score=87.9, age=19]
Student [id=67, name=明明, score=99.5, age=23]
Student [id=68, name=明明, score=87.9, age=19]
Student [id=69, name=明明, score=99.5, age=23]
Student [id=70, name=明明, score=87.9, age=19]
Student [id=71, name=明明, score=99.5, age=23]
Student [id=72, name=明明, score=87.9, age=19]
Student [id=73, name=明明, score=99.5, age=23]
Student [id=74, name=明明, score=87.9, age=19]
Student [id=75, name=明明, score=99.5, age=23]
Student [id=76, name=明明, score=87.9, age=19]
Student [id=77, name=明明, score=99.5, age=23]
Student [id=78, name=明明, score=87.9, age=19]
Student [id=79, name=明明, score=99.5, age=23]
Student [id=80, name=明明, score=87.9, age=19]
Student [id=81, name=明明, score=99.5, age=23]
Student [id=82, name=明明, score=87.9, age=19]
Student [id=83, name=明明, score=99.5, age=23]
Student [id=84, name=明明, score=87.9, age=19]
Student [id=85, name=明明, score=99.5, age=23]
Student [id=86, name=明明, score=87.9, age=19]
Student [id=87, name=明明, score=99.5, age=23]
Student [id=88, name=明明, score=87.9, age=19]
Student [id=89, name=明明, score=99.5, age=23]
Student [id=90, name=明明, score=87.9, age=19]
Student [id=91, name=明明, score=99.5, age=23]
Student [id=92, name=明明, score=87.9, age=19]
Student [id=93, name=明明, score=99.5, age=23]
Student [id=94, name=明明, score=87.9, age=19]
Student [id=95, name=明明, score=99.5, age=23]
Student [id=100, name=明明, score=87.9, age=19]
Student [id=101, name=明明, score=99.5, age=23]
Student [id=104, name=明明, score=87.9, age=19]
Student [id=105, name=明明, score=99.5, age=23]
Student [id=106, name=明明, score=87.9, age=19]
Student [id=107, name=明明, score=87.9, age=19]
Student [id=108, name=明明, score=87.9, age=19]
Student [id=109, name=明明, score=87.9, age=19]
Student [id=110, name=明明, score=87.9, age=19]
Student [id=111, name=明明, score=87.9, age=19]
Student [id=112, name=明明, score=87.9, age=19]
Student [id=113, name=明明, score=87.9, age=19]
Student [id=114, name=明明, score=99.5, age=23]
Student [id=115, name=明明, score=87.9, age=19]
Student [id=116, name=明明, score=99.5, age=23]
Student [id=117, name=明明, score=87.9, age=19]
Student [id=118, name=明明, score=99.5, age=23]
DEBUG [main] - ==>  Preparing: select id,name,age,score from student
DEBUG [main] - ==> Parameters:
DEBUG [main] - <==      Total: 95
Student [id=35, name=王维, score=93.5, age=23]
DEBUG [main] - ==>  Preparing: select id,name,age,score from student where id=?
DEBUG [main] - ==> Parameters: 33(Integer)
DEBUG [main] - <==      Total: 1
Student [id=33, name=王二维, score=93.5, age=23]
DEBUG [main] - ==>  Preparing: select id,name,age,score from student where name like '%王二%'
DEBUG [main] - ==> Parameters:
DEBUG [main] - <==      Total: 3
Student [id=29, name=安抚王二, score=93.5, age=23]
Student [id=32, name=王二分, score=93.5, age=23]
Student [id=33, name=王二维, score=93.5, age=23]