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javabean中
package com.sxt.bean;
import org.apache.ibatis.type.Alias;
public class Employee {
private int id;
private String last_name;
private String gender;
private String email;
public Employee() {
}
public Employee(int id, String last_name, String gender, String email) {
this.id = id;
this.last_name = last_name;
this.gender = gender;
this.email = email;
}
@Override
public String toString() {
return "Employee{" +
"id=" + id +
", last_name='" + last_name + '\'' +
", gender='" + gender + '\'' +
", email='" + email + '\'' +
'}';
}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getLast_name() {
return last_name;
}
public void setLast_name(String last_name) {
this.last_name = last_name;
}
public String getGender() {
return gender;
}
public void setGender(String gender) {
this.gender = gender;
}
public String getEmail() {
return email;
}
public void setEmail(String email) {
this.email = email;
}
}
接口中定义增删改查的方法
package com.sxt.dao;
import com.sxt.bean.Employee;
public interface EmployMapper {
public Employee getEmpById(Integer id);
public Long addEmp(Employee employee);
public boolean updateEmp(Employee employee);
public void deleteEmpById(Integer id);
}
全局配置文件
<?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="db.properties"></properties>
<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="${jdbc.name}" />
<property name="password" value="${jdbc.pwd}" />
</dataSource>
</environment>
</environments>
<!-- 将我们写好的sql映射文件(EmployeeMapper.xml)一定要注册到全局配置文件(mybatis-config.xml)中 -->
<mappers>
<mapper resource="EmployeeMapper.xml" />
</mappers>
</configuration>
映射文件
<?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">
<mapper namespace="com.sxt.dao.EmployMapper">
<!--
namespace:名称空间;指定为接口的全类名
id:唯一标识
resultType:返回值类型
#{id}:从传递过来的参数中取出id值
public Employee getEmpById(Integer id);
-->
<select id="getEmpById" resultType="com.sxt.bean.Employee">
select id,last_name,gender,email from tbl_employee where id = #{id}
</select>
<!--public void addEmp(Employee employee);-->
<!--public void updateEmp(Employee employee);-->
<!--public void deleteEmpById(Integer id);-->
<!--员工添加方法-->
<insert id="addEmp" parameterType="com.sxt.bean.Employee">
INSERT INTO tbl_employee(last_name,email,gender) VALUES(#{last_name},#{email},#{gender})
</insert>
<update id="updateEmp">
UPDATE tbl_employee SET last_name=#{last_name},email=#{email},gender=#{gender} WHERE id=#{id}
</update>
<delete id="deleteEmpById">
DELETE FROM tbl_employee WHERE id=#{id}
</delete>
</mapper>
测试类的实现
//1.根据配置的xml文件(全局配置文件,创建一个sqlsessionfactory对象,有数据源一些运行环境)
public SqlSessionFactory getSqlSessionFactory () throws IOException {
String resource = "mybatis-config.xml";
InputStream inputStream = Resources.getResourceAsStream(resource);
return new SqlSessionFactoryBuilder().build(inputStream);
}
@Test
public void test03() throws IOException {
SqlSessionFactory sqlSessionFactory = getSqlSessionFactory();
//1.获取到sqlsession不会自动提交
SqlSession openSession = sqlSessionFactory.openSession();
try {
EmployMapper mapper = openSession.getMapper(EmployMapper.class);
//添加操作
//Employee employee = new Employee(2,"Tom","1","[email protected]");
//mapper.addEmp(employee);
//修改操作
Employee employee = new Employee(1,"Tom1","0","[email protected]");
boolean updateEmp= mapper.updateEmp(employee);
System.out.println(updateEmp);
//删除操作
//mapper.deleteEmpById(2);
//2.手动提交数据
openSession.commit();
}finally {
openSession.close();
}
}
获取自增主键的值:
mysql支持自增主键,其获取通过statement.getGenreatedKeys();
userGeneratedKeys=“true”;使用自增主键获取主键值策略
keyProperty:指定对应的主键属性,mybatis获取到主键之后,将值封装给javaBean的哪个属性
核心代码
Employee employee = new Employee(2,"Tom","1","[email protected]");
mapper.addEmp(employee);
System.out.println(employee.getId());
映射的xml文件
insert id="addEmp" parameterType="com.sxt.bean.Employee"
useGeneratedKeys="true" keyProperty="id">
INSERT INTO tbl_employee(last_name,email,gender) VALUES(#{last_name},#{email},#{gender})
</insert>
根据培训机构视频自学编写的代码