目录
一、配置xml文件
步骤
1、创建pojo类（Student对象）
2、创建StudentMapper接口
3、创建mapper.xml配置文件
4、在mymybatis-config.xml中添加StudentMapper配置
5、创建测试类
二、注解绑定
步骤
1、创建pojo类（Teacher 对象）
2、创建TeacherMapper接口
3、更改配置
4、创建测试类TeacherMapperTest
mybatis实现了接口绑定，使用会更加方便
接口绑定：mybatis中任意定义接口，然后把接口里面的方法和SQL语句绑定，就可以直接调用接口方法就可以
接口绑定方式：
通过注解绑定，直接在方法上面加上@Select @Update等注解，在注解里包含SQL绑定
通过XML里面SQL绑定，需要在xml配置文件里的namespace必须指定接口的全限定名
一、配置xml文件
步骤
1、创建pojo类（自定义对象类）
2、创建mapper.java接口
3、创建mapper.xml配置文件
4、在mymybatis-config.xml中添加mapper配置
5、创建测试类
1、创建pojo类（自定义对象类）
2、创建mapper.java接口
3、创建mapper.xml配置文件
4、在mymybatis-config.xml中添加mapper配置
5、创建测试类
这里以student表为例进行编码：
1、创建pojo类（Student对象）
给定是四个属性 SID,Sname,Ssex,Sage
并 右击 generate 出他们的getter and setter 和 toString()方法
public class Student {
private Integer SID;
private String Sname;
private String Ssex;
private Integer Sage;
public Integer getSID() {
return SID;
}
public void setSID(Integer SID) {
this.SID = SID;
}
public String getSname() {
return Sname;
}
public void setSname(String sname) {
Sname = sname;
}
public String getSsex() {
return Ssex;
}
public void setSsex(String ssex) {
Ssex = ssex;
}
public Integer getSage() {
return Sage;
}
public void setSage(Integer sage) {
Sage = sage;
}
@Override
public String toString() {
return "Student{" +
"SID=" + SID +
", Sname='" + Sname + ''' +
", Ssex='" + Ssex + ''' +
", Sage=" + Sage +
'}';
}
}
2、创建StudentMapper接口
import com.tulun.pojo.Student;
import java.util.List;
public interface StudentMapper {
//通过id来查询某一个学生信息
// @Select("select * from cheche where SID = #{id}")
public Student selectStudentById(Integer id);
// 通过id删除某条学生数据
public void deleteStudentById(Integer id);
//查询所有数据
public List selectAllStudent();
//动态查询数据
public List selectStudent(Student student);
}
3、创建mapper.xml配置文件
4、在mymybatis-config.xml中添加StudentMapper配置
5、创建测试类
import com.tulun.pojo.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.Iterator;
import java.util.List;
public class StudentMapperTest {
SqlSessionFactory sqlSessionFactory = null;
@Before
public void before(){
String resource = "mybatis-config.xml";
InputStream stream = null;
try {
stream = Resources.getResourceAsStream(resource);
} catch (IOException e) {
e.printStackTrace();
}
sqlSessionFactory = new SqlSessionFactoryBuilder().build(stream);
System.out.println("before方法执行结束");
}
@Test
public void selectStudentById() {
System.out.println("查询数据的方法开始执行");
//获取会话
SqlSession sqlSession = sqlSessionFactory.openSession();
//第一种 原始直接调用方法
// Student o = sqlSession.selectOne("com.tulun.mapper.StudentMapper.selectStudentById",2);
// System.out.println(o);
//第二种方法 代理模式 代理对象需要依赖于原始调用方法
//通过接口获取对象实例
StudentMapper studentMapper = sqlSession.getMapper(StudentMapper.class);
//测试接口
Student student = studentMapper.selectStudentById(2);
System.out.println(student);
}
@Test
public void selectAllStudent() {
System.out.println("查询数据的方法开始执行");
//获取会话
SqlSession sqlSession = sqlSessionFactory.openSession();
//原始调用方式
// List student = sqlSession.selectList("com.tulun.mapper.StudentMapper.selectAllStudent");
// Iterator iterator1 = student.iterator();
// while (iterator1.hasNext()){
// System.out.println(iterator1.next());
// }
// System.out.println("-------------------------------");
StudentMapper mapper = sqlSession.getMapper(StudentMapper.class);
List selectAllStudent = mapper.selectAllStudent();
Iterator iterator = selectAllStudent.iterator();
while (iterator.hasNext()){
System.out.println(iterator.next());
}
}
@Test
public void deleteStudentById() {
System.out.println("删除方法开始执行");
//获取会话
SqlSession sqlSession = sqlSessionFactory.openSession();
//通过接口获取对象实例
StudentMapper studentMapper = sqlSession.getMapper(StudentMapper.class);
studentMapper.deleteStudentById(2);
sqlSession.commit();
}
@Test
public void selectStudent(){
//获取会话
SqlSession sqlSession = sqlSessionFactory.openSession();
StudentMapper studentMapper = sqlSession.getMapper(StudentMapper.class);
Student student = new Student();
student.setSID(1);
student.setSname("88");
// List students = studentMapper.selectStudent(student);
//
// Iterator iterator = students.iterator();
// while (iterator.hasNext()){
// System.out.println(iterator.next());
// }
}
@After
public void after() {
System.out.println("after方法执行结束");
}
}
4、在mymybatis-config.xml中添加StudentMapper配置
5、创建测试类
import com.tulun.pojo.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.Iterator;
import java.util.List;
public class StudentMapperTest {
SqlSessionFactory sqlSessionFactory = null;
@Before
public void before(){
String resource = "mybatis-config.xml";
InputStream stream = null;
try {
stream = Resources.getResourceAsStream(resource);
} catch (IOException e) {
e.printStackTrace();
}
sqlSessionFactory = new SqlSessionFactoryBuilder().build(stream);
System.out.println("before方法执行结束");
}
@Test
public void selectStudentById() {
System.out.println("查询数据的方法开始执行");
//获取会话
SqlSession sqlSession = sqlSessionFactory.openSession();
//第一种 原始直接调用方法
// Student o = sqlSession.selectOne("com.tulun.mapper.StudentMapper.selectStudentById",2);
// System.out.println(o);
//第二种方法 代理模式 代理对象需要依赖于原始调用方法
//通过接口获取对象实例
StudentMapper studentMapper = sqlSession.getMapper(StudentMapper.class);
//测试接口
Student student = studentMapper.selectStudentById(2);
System.out.println(student);
}
@Test
public void selectAllStudent() {
System.out.println("查询数据的方法开始执行");
//获取会话
SqlSession sqlSession = sqlSessionFactory.openSession();
//原始调用方式
// List student = sqlSession.selectList("com.tulun.mapper.StudentMapper.selectAllStudent");
// Iterator iterator1 = student.iterator();
// while (iterator1.hasNext()){
// System.out.println(iterator1.next());
// }
// System.out.println("-------------------------------");
StudentMapper mapper = sqlSession.getMapper(StudentMapper.class);
List selectAllStudent = mapper.selectAllStudent();
Iterator iterator = selectAllStudent.iterator();
while (iterator.hasNext()){
System.out.println(iterator.next());
}
}
@Test
public void deleteStudentById() {
System.out.println("删除方法开始执行");
//获取会话
SqlSession sqlSession = sqlSessionFactory.openSession();
//通过接口获取对象实例
StudentMapper studentMapper = sqlSession.getMapper(StudentMapper.class);
studentMapper.deleteStudentById(2);
sqlSession.commit();
}
@Test
public void selectStudent(){
//获取会话
SqlSession sqlSession = sqlSessionFactory.openSession();
StudentMapper studentMapper = sqlSession.getMapper(StudentMapper.class);
Student student = new Student();
student.setSID(1);
student.setSname("88");
// List students = studentMapper.selectStudent(student);
//
// Iterator iterator = students.iterator();
// while (iterator.hasNext()){
// System.out.println(iterator.next());
// }
}
@After
public void after() {
System.out.println("after方法执行结束");
}
}
import com.tulun.pojo.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.Iterator;
import java.util.List;
public class StudentMapperTest {
SqlSessionFactory sqlSessionFactory = null;
@Before
public void before(){
String resource = "mybatis-config.xml";
InputStream stream = null;
try {
stream = Resources.getResourceAsStream(resource);
} catch (IOException e) {
e.printStackTrace();
}
sqlSessionFactory = new SqlSessionFactoryBuilder().build(stream);
System.out.println("before方法执行结束");
}
@Test
public void selectStudentById() {
System.out.println("查询数据的方法开始执行");
//获取会话
SqlSession sqlSession = sqlSessionFactory.openSession();
//第一种 原始直接调用方法
// Student o = sqlSession.selectOne("com.tulun.mapper.StudentMapper.selectStudentById",2);
// System.out.println(o);
//第二种方法 代理模式 代理对象需要依赖于原始调用方法
//通过接口获取对象实例
StudentMapper studentMapper = sqlSession.getMapper(StudentMapper.class);
//测试接口
Student student = studentMapper.selectStudentById(2);
System.out.println(student);
}
@Test
public void selectAllStudent() {
System.out.println("查询数据的方法开始执行");
//获取会话
SqlSession sqlSession = sqlSessionFactory.openSession();
//原始调用方式
// List student = sqlSession.selectList("com.tulun.mapper.StudentMapper.selectAllStudent");
// Iterator iterator1 = student.iterator();
// while (iterator1.hasNext()){
// System.out.println(iterator1.next());
// }
// System.out.println("-------------------------------");
StudentMapper mapper = sqlSession.getMapper(StudentMapper.class);
List selectAllStudent = mapper.selectAllStudent();
Iterator iterator = selectAllStudent.iterator();
while (iterator.hasNext()){
System.out.println(iterator.next());
}
}
@Test
public void deleteStudentById() {
System.out.println("删除方法开始执行");
//获取会话
SqlSession sqlSession = sqlSessionFactory.openSession();
//通过接口获取对象实例
StudentMapper studentMapper = sqlSession.getMapper(StudentMapper.class);
studentMapper.deleteStudentById(2);
sqlSession.commit();
}
@Test
public void selectStudent(){
//获取会话
SqlSession sqlSession = sqlSessionFactory.openSession();
StudentMapper studentMapper = sqlSession.getMapper(StudentMapper.class);
Student student = new Student();
student.setSID(1);
student.setSname("88");
// List students = studentMapper.selectStudent(student);
//
// Iterator iterator = students.iterator();
// while (iterator.hasNext()){
// System.out.println(iterator.next());
// }
}
@After
public void after() {
System.out.println("after方法执行结束");
}
}
二、注解绑定
步骤
1、创建pojo类
2、创建mapper.java接口
3、在mybatis-config.xml中添加mapper配置
4、创建测试类
1、创建pojo类
2、创建mapper.java接口
3、在mybatis-config.xml中添加mapper配置
4、创建测试类
这里以teacher表为例进行编码：
1、创建pojo类（Teacher 对象）
给定是三个属性 id,name,sex
并 右击 generate 出他们的getter and setter 和 toString()方法
public class Teacher {
private Integer id;
private String name;
private String sex;
@Override
public String toString() {
return "Teacher{" +
"id=" + id +
", name='" + name + ''' +
", sex='" + sex + ''' +
'}';
}
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 String getSex() {
return sex;
}
public void setSex(String sex) {
this.sex = sex;
}
}
2、创建TeacherMapper接口
里面给定要操作数据库的方法
在方法的 上方 写上sql语句
格式为： @Insert("sql语句")
import org.apache.ibatis.annotations.*;
import com.tulun.pojo.Teacher;
import java.util.List;
interface TeacherMapper {
//注解形式
// @Results(id="teacherResult",value = {
// @Result(property = "id",column = "id",id =true),
// @Result(property = "s",column = "sex")}
// )
//选择
@Select("select * from teacher where id = #{id}")
public Teacher selectTeacherById(Integer id);
//删除
@Delete("delect from teacher where id = #{id}")
public void deleteTeacherById(Integer id);
//更新
//这个更新我还没研究好
public int updateTeacherById(String sex, String name);
//添加
// @Options(useGeneratedKeys = true ,keyColumn = "id")
@Insert("insert into teacher(id,name,sex) values (#{id},#{name},#{sex})")
public int insertTeacherById(Teacher teacher);
}
3、更改配置
将mybatis-config.xml中的mapper标签里的内容更改
4、创建测试类TeacherMapperTest
import com.tulun.pojo.Teacher;
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.Before;
import org.junit.Test;
import java.io.IOException;
import java.io.InputStream;
import static org.junit.Assert.*;
public class TeacherMapperTest {
SqlSessionFactory sqlSessionFactory = null;
@Before
public void before(){
String resource = "mybatis-config.xml";
InputStream stream = null;
try {
stream = Resources.getResourceAsStream(resource);
} catch (IOException e) {
e.printStackTrace();
}
sqlSessionFactory = new SqlSessionFactoryBuilder().build(stream);
System.out.println("before方法执行结束");
}
@Test
public void selectTeacherById() {
}
@Test
public void deleteTeacherById() {
}
@Test
public void updateTeacherById() {
}
@Test
public void insertTeacherById() {
SqlSession sqlSession = sqlSessionFactory.openSession();
TeacherMapper teacherMapper = sqlSession.getMapper(TeacherMapper.class);
Teacher teacher = new Teacher();
teacher.setId(10);
teacher.setName("jing");
teacher.setSex("nv");
teacherMapper.insertTeacherById(teacher);
sqlSession.commit();
}
}
这里主要演示一下 插入操作（其余操作类似）
插入一组数据（id是10，name是jing,sex 是nv）
执行操作之前数据库里的内容：
执行插入操作之后数据库内容为：
插入成功！
这里还有一个知识点关于属性值自增问题
@Options(useGeneratedKeys = true ,keyColumn = "id") 在sql上方将自增的属性值打开，并指定id是哪个自增属性。
假如id可以自增，那在TeacherMapperTest类中传参数时不需要传入id值，在数据库中会根据id字段中最大的数据接着自增。
@Options(useGeneratedKeys = true ,keyColumn = "id")
@Insert("insert into teacher(id,name,sex) values (#{id},#{name},#{sex})")
public int insertTeacherById(Teacher teacher);
再次运行插入结果如下：
在java代码中打开自增的按钮，还需要你的数据库中该属性可以有主键和自增的约束，在我的数据库中，teacher表中的id属性约束是：
@select操作
当java中teacher对象中的属性和数据库中的属性名完全一致时，会自动识别映射
但当java中属性sex变成s时，和数据库中的sex不匹配，想要吧他俩匹配起来，要怎样做呢?
在TeacherMapper.java中添加如下代码，这样可以将java中的属性和数据库中的属性进行匹配
@Results(id="teacherResult",value = {
@Result(property = "id",column = "id",id =true),
@Result(property = "s",column = "sex")}
)
@Select("select * from teacher where id = #{id}")
public Teacher selectTeacherById(Integer id);
@select
查询表中的所有数据
StudentMapper.java 类中的方法
public ListselectAllStudent();
StudentMapperTest.java类中selectALLStudent方法：
SqlSessionFactory sqlSessionFactory = null;
@Before
public void before(){
String resource = "mybatis-config.xml";
InputStream stream = null;
try {
stream = Resources.getResourceAsStream(resource);
} catch (IOException e) {
e.printStackTrace();
}
sqlSessionFactory = new SqlSessionFactoryBuilder().build(stream);
System.out.println("before方法执行结束");
}
@Test
public void selectAllStudent() {
System.out.println("查询数据的方法开始执行");
//获取会话
SqlSession sqlSession = sqlSessionFactory.openSession();
StudentMapper mapper = sqlSession.getMapper(StudentMapper.class);
List selectAllStudent = mapper.selectAllStudent();
//把获取的Student对象一一打印出来
Iterator iterator = selectAllStudent.iterator();
while (iterator.hasNext()){
System.out.println(iterator.next());
}
}
执行结果：
添加原始调用方式来进行比较，可以得到同样的结果。
SqlSessionFactory sqlSessionFactory = null;
@Before
public void before(){
String resource = "mybatis-config.xml";
InputStream stream = null;
try {
stream = Resources.getResourceAsStream(resource);
} catch (IOException e) {
e.printStackTrace();
}
sqlSessionFactory = new SqlSessionFactoryBuilder().build(stream);
System.out.println("before方法执行结束");
}
@Test
public void selectAllStudent() {
System.out.println("查询数据的方法开始执行");
//获取会话
SqlSession sqlSession = sqlSessionFactory.openSession();
//原始调用方式
List student = sqlSession.selectList("com.tulun.mapper.StudentMapper.selectAllStudent");
Iterator iterator1 = student.iterator();
while (iterator1.hasNext()){
System.out.println(iterator1.next());
}
System.out.println("-------------------------------");
StudentMapper mapper = sqlSession.getMapper(StudentMapper.class);
List selectAllStudent = mapper.selectAllStudent();
//把获取的Student对象一一打印出来
Iterator iterator = selectAllStudent.iterator();
while (iterator.hasNext()){
System.out.println(iterator.next());
}
}
