【MyBatis入门】—— 第一个MyBatis应用

prollerweg

1.创建STUDENTS表并插入一些数据：

-- 创建数据库
CREATE DATABASE mybatis;
-- 使用数据库
USE mybatis;
-- 创建表
CREATE TABLE STUDENT (
id BIGINT(20) NOT NULL AUTO_INCREMENT COMMENT 'PK',
name VARCHAR(30) NOT NULL COMMENT '名称',
email VARCHAR(30) NOT NULL COMMENT '邮箱',
dob DATE DEFAULT NULL,
PRIMARY KEY(id)
) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=gbk COMMENT '学生表';
-- 插入数据
INSERT INTO STUDENT(name, email, dob) VALUES('student1', 'student1@qq.com', '1990-01-01');
INSERT INTO STUDENT(name, email, dob) VALUES('student2', 'student2@qq.com', '1990-02-02');
 
2. 创建一个总的目录（文件夹名为mybatis-demos），用于存放所有的MyBatis应用示例
 
3. 打开DOS命令行窗体，进入到上面创建的文件夹mybatis-demos。使用Maven Archetype生成项目骨架：
3.1 输入命令：mvn archetype:generate

 
 3.2 在运行到“Choose a number or apply filter (format: [groupId:]artifactId, case sensitive contains): 580:”和“Choose org.apache.maven.archetypes:maven-archetype-quickstart version:”外时直接敲回车

 
3.3 输入项目的groupId、artifactId、version、package，然后检查输入的groupId、artifactId、version、package信息是否正确，输入“Y”确认

 
使用Maven Archetype生成的项目的目录结构：

 
4. 修改mybatis-demo-01文件夹下的pom.xml文件，添加项目运行需要的依赖：

<dependencies>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.11</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis</artifactId>
<version>3.2.7</version>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.22</version>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-log4j12</artifactId>
<version>1.7.7</version>
</dependency>
</dependencies>
 
5. 在mybatis-demo-01\src\main\java\com\github\wangguocheng\mybatis\demo文件夹下新domain文件夹，然后在domain文件夹下创建Student实体类：
Student.java

package com.github.wangguocheng.mybatis.demo.domain;
import java.util.Date;
public class Student {
private long id;
private String name;
private String email;
private Date dob;
public Student() {}
public long getId() {
return id;
}
public void setId(long id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getEmail() {
return email;
}
public void setEmail(String email) {
this.email = email;
}
public Date getDob() {
return dob;
}
public void setDob(Date dob) {
this.dob = dob;
}
}

 
6.在mybatis-demo-01\src\main\java\com\github\wangguocheng\mybatis\demo文件夹下新建mapper文件夹，然后在mapper文件夹下创建StudentMapper类及StudentMapper.xml映射文件：
StudentMapper.java

package com.github.wangguocheng.mybatis.demo.mapper;
import java.util.List;
import com.github.wangguocheng.mybatis.demo.domain.Student;
public interface StudentMapper {
public void insertStudent(Student student);
public List<Student> findAllStudents();
public Student findStudentById(long id);
}

 
StudentMapper.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 namespace="com.github.wangguocheng.mybatis.demo.mapper.StudentMapper">
<resultMap type="Student" id="StudentResultMap">
<id property="id" column="id"/>
<result property="name" column="name"/>
<result property="email" column="email"/>
<result property="dob" column="dob"/>
</resultMap>
<select id="insertStudent" parameterType="Student">
INSERT INTO STUDENT(name, email, dob)
VALUES(#{name}, #{email}, #{dob})
</select>
<select id="findAllStudents" resultMap="StudentResultMap">
SELECT * FROM STUDENT
</select>
<select id="findStudentById" resultMap="StudentResultMap" parameterType="long">
SELECT * FROM STUDENT WHERE id = #{id}
</select>
</mapper>
 
　　7. 在mybatis-demo-01\src\main文件夹下新建resources文件夹，然后在resources文件夹下创建mybatis配置文件及log4j配置文件
　　mybaits.xml

<?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>
<!-- 定义类型别名 -->
<typeAliases>
<typeAlias type="com.github.wangguocheng.mybatis.demo.domain.Student" alias="Student"/>
</typeAliases>
<environments default="development">
<environment id="development">
<transactionManager type="JDBC"/>
<dataSource type="POOLED">
<property name="driver" value="com.mysql.jdbc.Driver"/>
<property name="url" value="jdbc:mysql://localhost:3306/mybatis"/>
<property name="username" value="root"/>
<property name="password" value="abc123"/>
</dataSource>
</environment>
</environments>
<mappers>
<mapper resource="com/github/wangguocheng/mybatis/demo/mapper/StudentMapper.xml"/>
</mappers>
</configuration>
　　log4j.properties

log4j.rootLogger=DEBUG, stdout
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%d [%-5p] %c - %m%n
　　8. 在mybatis-demo-01\src\main\java\com\github\wangguocheng\mybatis\demo文件夹下新建util文件夹，然后在util文件夹下创建工具类
　　MyBatisSqlSessionFactory.java

package com.github.wangguocheng.mybatis.demo.util;
import java.io.IOException;
import java.io.InputStream;
import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;
public class MyBatisSqlSessionFactory {
private static SqlSessionFactory sqlSessionFactory;
public static SqlSessionFactory getSqlSessionFactory() {
if(sqlSessionFactory == null) {
InputStream inputStream = null;
try {
inputStream = Resources.getResourceAsStream("mybatis.xml");
sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
} catch(IOException e) {
throw new RuntimeException(e.getCause());
}
}
return sqlSessionFactory;
}
public static SqlSession openSession() {
return getSqlSessionFactory().openSession();
}
}

　　 
　　9. 修改pom.xml文件，在<build>节点下添加如下代码：

<resources>
<resource>
<directory>src/main/java</directory>
<includes>
<include>**/*.xml</include>
</includes>
<filtering>true</filtering>
</resource>
<resource>
<directory>src/main/resources</directory>
</resource>
</resources>
　　 
　　10. 在mybatis-demo-01\src\main\java\com\github\wangguocheng\mybatis\demo文件夹下新建service文件夹，然后在service文件夹下创建StudentService类
　　StudentService.java

package com.github.wangguocheng.mybatis.demo.service;
import java.util.List;
import org.apache.ibatis.session.SqlSession;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.github.wangguocheng.mybatis.demo.domain.Student;
import com.github.wangguocheng.mybatis.demo.mapper.StudentMapper;
import com.github.wangguocheng.mybatis.demo.util.MyBatisSqlSessionFactory;
public class StudentService {
private Logger logger = LoggerFactory.getLogger(getClass());
public List<Student> findAllStudents() {
SqlSession sqlSession = MyBatisSqlSessionFactory.openSession();
try {
StudentMapper studentMapper = sqlSession.getMapper(StudentMapper.class);
return studentMapper.findAllStudents();
} finally {
sqlSession.close();
}
}
public Student findStudentById(Long id) {
logger.debug("Select Student By ID :{}", id);
SqlSession sqlSession = MyBatisSqlSessionFactory.openSession();
try {
StudentMapper studentMapper = sqlSession.getMapper(StudentMapper.class);
return studentMapper.findStudentById(id);
} finally {
sqlSession.close();
}
}
public void createStudent(Student student) {
SqlSession sqlSession = MyBatisSqlSessionFactory.openSession();
try {
StudentMapper studentMapper = sqlSession.getMapper(StudentMapper.class);
studentMapper.insertStudent(student);
sqlSession.commit();
} finally {
sqlSession.close();
}
}
}

　　 
　　11. 在mybatis-demo-01\src\test\java\com\github\wangguocheng\mybatis\demo\service文件夹下新建service文件夹，然后在service文件夹下创建StudentServiceTest类
　　StudentServiceTest.java

package com.github.wangguocheng.mybatis.demo.service;
import java.util.Date;
import java.util.List;
import org.junit.AfterClass;
import org.junit.Assert;
import org.junit.BeforeClass;
import org.junit.Test;
import com.github.wangguocheng.mybatis.demo.domain.Student;
public class StudentServiceTest {
private static StudentService studentService;
@BeforeClass
public static void setup() {
studentService = new StudentService();
}
@AfterClass
public static void tearDown() {
studentService = null;
}
@Test
public void testFindAllStudents() {
List<Student> students = studentService.findAllStudents();
Assert.assertNotNull(students);
for(Student student : students) {
System.out.println(student);
}
}
@Test
public void testFindStudentById() {
Student student = studentService.findStudentById(1L);
Assert.assertNotNull(student);
System.out.println(student);
}
@Test
public void testCreateStudent() {
Student student = new Student();
student.setName("new-student-02");
student.setEmail("new-student-02@163.com");
student.setDob(new Date());
studentService.createStudent(student);
}
}

　　 
　　12. 在DOS命令窗体中进入mybatis-demo-01文件夹，并运行命令mvn clean test

 
　　项目源码见随附件