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coolcoolercool/itheima_dao_UserDao.java

Created June 20, 2018 13:43
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Raw
itheima_dao_UserDao.java
package cn.itheima.dao;
import cn.itheima.pojo.User;
import java.util.List;
/**
* author: zzw5005
* date: 2018/6/20 19:36
*/
public interface UserDao {
public User findUserById(Integer id);
public List<User> findUserName(String userName);
}
Raw
itheima_dao_UserDaoImpl.java
package cn.itheima.dao;
import cn.itheima.pojo.User;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import java.util.List;
/**
* author: zzw5005
* date: 2018/6/20 19:37
*/
public class UserDaoImpl implements UserDao {
private SqlSessionFactory sqlSessionFactory;
//通过构造方法注入
public UserDaoImpl(SqlSessionFactory sqlSessionFactory){
this.sqlSessionFactory = sqlSessionFactory;
}
@Override
public User findUserById(Integer id) {
//sqlSession是线程不安全的，所以他的最佳使用范围在方法体内
SqlSession openSession = sqlSessionFactory.openSession();
User user = openSession.selectOne("test.findUserId", id);
return user;
}
@Override
public List<User> findUserName(String userName) {
SqlSession openSession = sqlSessionFactory.openSession();
List<User> list = openSession.selectList("test.findUserByUserName", userName);
return null;
}
}
Raw
itheima_mapper_UserMapper.java
package cn.itheima.mapper;
import cn.itheima.pojo.User;
import java.util.List;
/**
* author: zzw5005
* date: 2018/6/20 19:42
*/
public interface UserMapper {
public User findUserById(Integer id);
//动态代理形势中，如果返回结果集List,那么mybatis
//会在生成实现类的使用会自动调用slectList方法
public List<User> findUserByUserName(String userName);
public void insertUser(User user);
}
Raw
itheima_mapper_UserMapper.xml
<?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接口代理实现编写规则:
1. 映射文件中namespace要等于接口的全路径名称
2. 映射文件中sql语句id要等于接口的方法名称
3. 映射文件中传入参数类型要等于接口方法的传入参数类型
4. 映射文件中返回结果集类型要等于接口方法的返回值类型
-->
<mapper namespace="cn.itheima.mapper.UserMapper">
<!--
id:sql语句唯一标识
parameType:指定传入参数类型
resultType:返回结果集类型
#{}占位符:起到占位作用,
如果传入的是基本类型(string,long,double,int,boolean,float等),那么#{}中的变量名称可以随意写.
-->
<select id="findUserById" parameterType="int" resultType="cn.itheima.pojo.User">
select * from user where id =#{id}
</select>
<!--
如果返回结果为集合，可以调用selectList方法，这个方法返回的结果就是一个集合，所以映射文件中应该
配置成集合泛型的类型
${}拼接符:字符串原样拼接，如果传入的参数是基本类型(String,long,double,int ,boolean,float等),
那么${}中的变量名称必须是value
注意:拼接符有sql注入的风险，所以谨慎使用
-->
<select id="findUserByUserName" parameterType="string" resultType="user">
select * from user where username like '%${value}'
</select>
<!--
执行select LAST_INSERT_ID() 数据库函数，返回自增的主键
keyProperty:价格返回的主键放入传入参数的id中保存
order:当前函数相对与insert语句的执行顺序，在insert之前执行的是before，在insert后执行的AFTER
resultType:id的类型，也就是keyproperty中属性的类型
-->
<insert id="insertUser" parameterType="cn.itheima.pojo.User">
<selectKey keyProperty="id" order="AFTER" resultType="java.lang.Integer">
select LAST_INSERT_ID()
</selectKey>
insert into user (username,birthday,sex,address) values(#{username}, #{birthday},#{sex}, #{address})
</insert>
</mapper>
Raw
itheima_pojo_User.java
package cn.itheima.pojo;
import java.util.Date;
/**
* author: zzw5005
* date: 2018/6/20 19:33
*/
public class User {
private int id;
private String username; //用户姓名
private String sex; //性别
private Date birthday; //生日
private String address; //地址
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public String getSex() {
return sex;
}
public void setSex(String sex) {
this.sex = sex;
}
public Date getBirthday() {
return birthday;
}
public void setBirthday(Date birthday) {
this.birthday = birthday;
}
public String getAddress() {
return address;
}
public void setAddress(String address) {
this.address = address;
}
}
Raw
itheima_test_UserTest.java
package cn.itheima.test;
import cn.itheima.pojo.User;
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.Test;
import java.io.InputStream;
import java.util.List;
/**
* author: zzw5005
* date: 2018/6/20 21:05
*/
public class UserTest {
@Test
public void testUserById() throws Exception{
String resource = "SqlMapConfig.xml";
//通过流将核心配置文件读取进来
InputStream inputStream = Resources.getResourceAsStream(resource);
//通过核心配置文件输入流来创建会话工厂
SqlSessionFactory factory = new SqlSessionFactoryBuilder().build(inputStream);
//通过工厂创建会话
SqlSession openSession = factory.openSession();
//第一个参数;所调用的sql语句 = namespace +...+sql的ID
User user = openSession.selectOne("test.findUserById", 1);
System.out.println(user);
openSession.close();
}
@Test
public void testFindUserByUserName() throws Exception{
String resource = "SqlMapConfig.xml";
InputStream inputStream = Resources.getResourceAsStream(resource);
SqlSessionFactory factory = new SqlSessionFactoryBuilder().build(inputStream);
SqlSession openSession = factory.openSession();
List<User> list = openSession.selectList("test.findUserByUserName", "王");
System.out.println(list);
}
}
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