JavaEE——Mybatis（14）--MyBatis逆向工程
MyBatis Generator：
• 简称MBG，是一个专门为MyBatis框架使用者定制的代码生成器，可以快速的根据表生成对应的映射文件，接口，以及bean类。支持基本的增删改查，以及QBC风格的条件查询。但是表连接、存储过程等这些复杂sql的定义需要我们手工编写
• 官方文档地址
http://www.mybatis.org/generator/
• 官方工程地址
https://github.com/mybatis/generator/releases
导入
在
中找到如何使用
在XML Configuration File Reference中有实例
mbg.xml
targetRuntime="MyBatis3Simple":生成简单版的CRUD
MyBatis3:豪华版
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE generatorConfiguration
PUBLIC "-//mybatis.org//DTD MyBatis Generator Configuration 1.0//EN"
"http://mybatis.org/dtd/mybatis-generator-config_1_0.dtd">
<generatorConfiguration>
<!--<classPathEntry location="/Program Files/IBM/SQLLIB/java/db2java.zip" />-->
<context id="DB2Tables" targetRuntime="MyBatis3Simple">
<!--jdbcConnection:指定如何连接到目标数据库-->
<jdbcConnection driverClass="com.mysql.jdbc.Driver"
connectionURL="jdbc:mysql://localhost:3306/db_person"
userId="root"
password="1234">
</jdbcConnection>
<javaTypeResolver >
<property name="forceBigDecimals" value="false" />
</javaTypeResolver>
<!--javaModelGenerator:指定JavaBean的生成策略
targetPackage="test.model"：目标包名
targetProject="\MBGTestProject\src"：目标工程，生成的是bean.Student类-->
<javaModelGenerator targetPackage="bean"
targetProject=".\src">
<property name="enableSubPackages" value="true" />
<property name="trimStrings" value="true" />
</javaModelGenerator>
<!--sqlMapGenerator: sql映射生成策略，生成的是conf/dao/StudentMapper.xml-->
<sqlMapGenerator targetPackage="dao"
targetProject=".\src\conf">
<property name="enableSubPackages" value="true" />
</sqlMapGenerator>
<!--javaClientGenerator:指定mapper接口所在的位置，生成的是dao.StudentMapper接口-->
<javaClientGenerator type="XMLMAPPER" targetPackage="dao"
targetProject=".\src">
<property name="enableSubPackages" value="true" />
</javaClientGenerator>
<!--指定要逆向分析哪些表:根据表要创建JavaBean-->
<table tableName="student" domainObjectName="Student"></table>
<table tableName="grade" domainObjectName="Grade"></table>
</context>
</generatorConfiguration>
运行mbg
@Test
public void testMbg() throws Exception {
List<String> warnings = new ArrayList<String>();
boolean overwrite = true;
File configFile = new File("mbg.xml");
ConfigurationParser cp = new ConfigurationParser(warnings);
Configuration config = cp.parseConfiguration(configFile);
DefaultShellCallback callback = new DefaultShellCallback(overwrite);
MyBatisGenerator myBatisGenerator = new MyBatisGenerator(config, callback, warnings);
myBatisGenerator.generate(null);
}
生成结果：
测试：
package test;
import bean.Student;
import dao.StudentMapper;
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.jupiter.api.Test;
import org.mybatis.generator.api.MyBatisGenerator;
import org.mybatis.generator.config.Configuration;
import org.mybatis.generator.config.xml.ConfigurationParser;
import org.mybatis.generator.internal.DefaultShellCallback;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.List;
public class Mybatis_mbgTest {
public SqlSessionFactory getSqlSessionFactory() throws IOException {
String resource = "conf/mybatis_config.xml";
InputStream inputStream = Resources.getResourceAsStream(resource);
return new SqlSessionFactoryBuilder().build(inputStream);
}
@Test
public void testMbg() throws Exception {
List<String> warnings = new ArrayList<String>();
boolean overwrite = true;
File configFile = new File("mbg.xml");
ConfigurationParser cp = new ConfigurationParser(warnings);
Configuration config = cp.parseConfiguration(configFile);
DefaultShellCallback callback = new DefaultShellCallback(overwrite);
MyBatisGenerator myBatisGenerator = new MyBatisGenerator(config, callback, warnings);
myBatisGenerator.generate(null);
}
@Test
public void testSimple() throws IOException {
SqlSessionFactory sqlsessionFactory = getSqlSessionFactory();
SqlSession openSession = sqlsessionFactory.openSession();
try{
StudentMapper studentMapper = openSession.getMapper( StudentMapper.class );
List<Student> students = studentMapper.selectAll();
for(Student student : students){
System.out.println(student.getId());
}
}finally {
openSession.close();
}
}
}
其中conf/mybatis_config.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>
<!--引入外部properties配置文件-->
<properties resource="conf\dbconfig.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="${jdbc.username}"/>
<property name="password" value="${jdbc.password}"/>
</dataSource>
</environment>
</environments>
<mappers>
<mapper resource="conf\dao\StudentMapper.xml"/>
</mappers>
</configuration>
conf/dbconfig.properties
jdbc.driver=com.mysql.jdbc.Driver jdbc.url=jdbc:mysql://127.0.0.1:3306/db_person jdbc.username=root jdbc.password=1234
带条件复杂查询
@Test
public void testMyBatis3() throws IOException{
SqlSessionFactory sqlSessionFactory = getSqlSessionFactory();
SqlSession openSession = sqlSessionFactory.openSession();
try{
EmployeeMapper mapper = openSession.getMapper(EmployeeMapper.class);
//xxxExample就是封装查询条件的
//1、查询所有
//List<Employee> emps = mapper.selectByExample(null);
//2、查询员工名字中有e字母的，和员工性别是1的
//封装员工查询条件的example
EmployeeExample example = new EmployeeExample();
//创建一个Criteria，这个Criteria就是拼装查询条件
//select id, last_name, email, gender, d_id from tbl_employee
//WHERE ( last_name like ? and gender = ? ) or email like "%e%"
Criteria criteria = example.createCriteria();
criteria.andLastNameLike("%e%");
criteria.andGenderEqualTo("1");
Criteria criteria2 = example.createCriteria();
criteria2.andEmailLike("%e%");
example.or(criteria2);
List<Employee> list = mapper.selectByExample(example);
for (Employee employee : list) {
System.out.println(employee.getId());
}
}finally{
openSession.close();
}
}
