MyBatis
一、MyBatis简介
</br>
1、MyBatis的优点
</br>
消除了大量的JDBC冗余代码
低学习曲线
友好的Spring集成支持
除本身的缓存外，能友好的第三方缓存类库集成支持
良好的性能
</br>
2、MyBatis简单实例
</br>
- 创建表
create table t_person
(
id int auto_increment not null primary key,
name varchar(20) not null,
age int,
address varchar(50)
);
- sql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>
<!-- 数据库连接的环境，可以配置多个环境 -->
<environments default="hello_mysql">
<!-- 环境 -->
<environment id="hello_mysql">
<!-- 事务管理的策略 type = "jdbc" or "managed" -->
<transactionManager type="jdbc"/>
<!-- 数据源 type = "pooled"连接池 or "unpooled"不用连接池 or "jndi"跟Spring用 -->
<dataSource type="pooled">
<property name="driver" value="org.gjt.mm.mysql.Driver"/>
<property name="url" value="jdbc:mysql://localhost:3306/test"/>
<property name="username" value="root"/>
<property name="password" value="root"/>
</dataSource>
</environment>
</environments>
<!-- 加载配置文件PersonMapper.xml -->
<mappers>
<mapper resource="com/xiao/mybatis/pojo/PersonMapper.xml"/>
</mappers>
</configuration>
- pojo类
package com.xiao.mybatis.pojo;
public class Person {
private int pid;
private String pname;
private int age;
private String address;
public Person() {
}
public Person(String pname,int age,String address){
this.pname = pname;
this.age = age;
this.address = address;
}
public int getPid() {
return pid;
}
public void setPid(int pid) {
this.pid = pid;
}
public String getPname() {
return pname;
}
public void setPname(String pname) {
this.pname = pname;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
public String getAddress() {
return address;
}
public void setAddress(String address) {
this.address = address;
}
public String toString() {
return "Person [pid=" + pid + ", pname=" + pname + ", age=" + age
+ ", address=" + address + "]";
}
}
- pojo配置文件
<?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.xiao.mybatis.pojo">
<!-- 插入 -->
<insert id="addPerson" parameterType="com.xiao.mybatis.pojo.Person" useGeneratedKeys="true" keyProperty="pid">
insert into t_person values(null,#{pname},#{age},#{address})
</insert>
<!-- 查询 -->
<select id="getPersonList" resultType="com.xiao.mybatis.pojo.Person">
select * from t_person
</select>
<select id="getPersonByPid" parameterType="int" resultType="com.xiao.mybatis.pojo.Person">
select * from t_person where pid = #{pid}
</select>
<!-- 更新 -->
<update id="updatePesron" parameterType="com.xiao.mybatis.pojo.Person">
update t_person set pname = #{pname} , age = #{age} , address = #{address} where pid = #{pid}
</update>
<!-- 删除 -->
<delete id="deletePerson" parameterType="int">
delete from t_person where pid = #{pid}
</delete>
</mapper>
- 测试类
package com.xiao.mybatis.test;
import java.io.IOException;
import java.io.InputStream;
import java.util.List;
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.xiao.mybatis.pojo.Person;
public class PersonDaoTest {
SqlSession session = null;
/**
* 在连接数据库前加载
*/
public void setUp() {
try {
// 1、加载配置文件sqlMapConfig.xml
InputStream resourceAsStream = Resources.getResourceAsStream("sqlMapConfig.xml");
// 2、解析配置文件sqlMapConfig.xml
SqlSessionFactory factory = new SqlSessionFactoryBuilder().build(resourceAsStream);
// 3、通过factory创建session对象
session = factory.openSession();
} catch (IOException e) {
e.printStackTrace();
}
}
/**
* 执行完操作后提交事务，以及关闭连接
*/
public void tearDown() {
// 5、提交或回滚
session.commit();// session.rollback();
// 6、关闭session
if (null != session) {
session.close();
}
}
// 一、插入数据
public void addPersonTest() {
setUp();
Person person = new Person("boss", 20, "China");
// 4、执行插入操作
int count = session.insert("com.xiao.mybatis.pojo.addPerson", person);
System.out.println(count > 0 ? "插入成功" : "插入失败");
tearDown();
}
// 二、查询数据
public void selectPersonTest() {
setUp();
List personList = session.selectList("com.xiao.mybatis.pojo.getPersonList");
System.out.println( null != personList ? "查询成功" : "查询失败");
if(null != personList){
System.out.println(personList.toString());
}
tearDown();
}
// 二、条件查询数据
public void selectPersonByIdTest() {
setUp();
Person person = (Person) session.selectOne("com.xiao.mybatis.pojo.getPersonByPid",new Integer(7));
System.out.println( null != person ? "查询数据成功" : "查询失败");
if(null != person){
System.out.println(person.toString());
}
tearDown();
}
// 三、修改数据
public void updatePersonTest(){
setUp();
Person person = new Person(5,"boss", 100, "America");
int count = session.update("com.xiao.mybatis.pojo.updatePesron", person);
System.out.println(count > 0 ? "修改成功" : "修改失败");
tearDown();
}
// 四、删除数据
public void deletePersonTest(){
setUp();
Person person = new Person(5,"boss", 100, "America");
int count = session.delete("com.xiao.mybatis.pojo.deletePerson", person);
System.out.println(count > 0 ? "删除成功" : "删除失败");
tearDown();
}
public static void main(String[] args) {
PersonDaoTest personDaoTest = new PersonDaoTest();
//personDaoTest.addPersonTest(); // 插入
//personDaoTest.selectPersonTest(); // 查询
personDaoTest.selectPersonByIdTest();
//personDaoTest.updatePersonTest(); // 修改
//personDaoTest.deletePersonTest(); // 删除
}
}
进行运行，查看运行结果
