声明：lombok插件如果你想用请自行下载，你也可以直接alt+insert来编写实体类
基于注解的形式只需要将配置文件里面的
<mapper resource="com/lp/dao/UserDao.xml"/>
改为
<mapper resource="com/lp/dao/UserDao.xml"/>
dao接口里面自行添加@注解
1、首先，导入依赖
<dependencies>
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis</artifactId>
<version>3.5.2</version>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.49</version>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.13</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
<version>1.2.17</version>
</dependency>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<version>1.18.12</version>
</dependency>
</dependencies>
实体类总不能少吧
@Data
@NoArgsConstructor
@AllArgsConstructor
public class User {
private Integer id;
private String username;
private Date birthday;
private String sex;
private String address;
}
2、配置mybatis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>
<environments default="localhost">
<environment id="localhost">
<transactionManager type="JDBC"/>
<!-- 配置数据库连接信息 -->
<dataSource type="POOLED">
<property name="driver" value="com.mysql.jdbc.Driver"/>
<property name="url" value="jdbc:mysql://localhost:3306/eesy?characterEncoding=utf-8"/>
<property name="username" value="root"/>
<property name="password" value="962464"/>
</dataSource>
</environment>
</environments>
<mappers>
<mapper resource="com/lp/dao/UserDao.xml"/>
</mappers>
</configuration>
3、log4j.properties
# Set root category priority to INFO and its only appender to CONSOLE.
#log4j.rootCategory=INFO, CONSOLE debug info warn error fatal
log4j.rootCategory=debug, CONSOLE, LOGFILE
# Set the enterprise logger category to FATAL and its only appender to CONSOLE.
log4j.logger.org.apache.axis.enterprise=FATAL, CONSOLE
# CONSOLE is set to be a ConsoleAppender using a PatternLayout.
log4j.appender.CONSOLE=org.apache.log4j.ConsoleAppender
log4j.appender.CONSOLE.layout=org.apache.log4j.PatternLayout
log4j.appender.CONSOLE.layout.ConversionPattern=%d{ISO8601} %-6r [%15.15t] %-5p %30.30c %x - %m\n
# LOGFILE is set to be a File appender using a PatternLayout.
log4j.appender.LOGFILE=org.apache.log4j.FileAppender
log4j.appender.LOGFILE.File=d:\axis.log
log4j.appender.LOGFILE.Append=true
log4j.appender.LOGFILE.layout=org.apache.log4j.PatternLayout
log4j.appender.LOGFILE.layout.ConversionPattern=%d{ISO8601} %-6r [%15.15t] %-5p %30.30c %x - %m\n
4、UserDao接口
public interface UserDao {
//查询所有
List<User> findAll();
//插入用户
void saveUser(User user);
//通过id删除
void deleteUserById(Integer id);
//更新/修改用户
void updateUser(User user);
//通过id查询
List<User> selectUserById(Integer id);
//模糊查询
List<User> selectByLike(String string);
//查询总数
Integer selectUserCount();
}
5、UserDao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.lp.dao.UserDao">
<select id="findAll" resultType="com.lp.domain.User">
select * from user ;
</select>
<insert id="saveUser" parameterType="com.lp.domain.User">
insert into user
(id,username,birthday,sex,address)
values
(#{id},#{username},#{birthday},#{sex},#{address});
</insert>
<delete id="deleteUserById" parameterType="int">
delete from user where id = #{id};
</delete>
<update id="updateUser" parameterType="com.lp.domain.User">
update user
set
username = #{username},birthday=#{birthday},sex=#{sex},address=#{address}
where id = #{id};
</update>
<select id="selectUserById" parameterType="int" resultType="com.lp.domain.User">
select * from user where id = #{id };
</select>
<select id="selectByLike" parameterType="String" resultType="com.lp.domain.User">
<!-- select * from user where username like #{username}; --><!-- 一般用这种形式 -->
select * from user where username like '%${username}%';
</select>
<select id="selectUserCount" resultType="int">
select count(id) from user ;
</select>
</mapper>
6、Test测试
public class test {
private InputStream inputStream;
private SqlSession sqlSession;
private UserDao mapper;
@Before
public void init() throws IOException {
inputStream = Resources.getResourceAsStream("MyBatisConfig.xml");
SqlSessionFactoryBuilder sessionFactoryBuilder = new SqlSessionFactoryBuilder();
SqlSessionFactory factory = sessionFactoryBuilder.build(inputStream);
sqlSession = factory.openSession();
mapper = sqlSession.getMapper(UserDao.class);
System.out.println("初始化完成！");
}
@After
public void destroy() throws IOException {
sqlSession.commit();
sqlSession.close();
inputStream.close();
System.out.println("资源关闭！");
}
@Test
public void findAll(){
List<User> userList = mapper.findAll();
for (User user : userList) {
System.out.println(user);
}
}
@Test
public void saveUser(){
//数据库已经设置id主键自增，id可以不用传值
mapper.saveUser(new User(null,
"zhangsan",
new Date(),
"男",
"北京市某某小区"));
}
@Test
public void deleteUserById(){
//数据库已经设置id主键自增，id可以不用传值
mapper.deleteUserById(49);
}
@Test
public void updateUser(){
//数据库已经设置id主键自增，id可以不用传值
mapper.updateUser(new User(49,
"张三",
new Date(),
"男",
"北京市某某小区"));
}
@Test
public void selectUserById(){
List<User> users = mapper.selectUserById(48);
System.out.println(users);
}
@Test
public void selectByLike(){
// List<User> users = mapper.selectByLike("%王%");//一般用这种形式
List<User> users = mapper.selectByLike("王");
for (User user : users) {
System.out.println(user);
}
}
@Test
public void selectUserCount(){
Integer integer = mapper.selectUserCount();
System.out.println(integer);
}
}