逆向工程可以快速将数据库的表生成JavaBean,同时生成对单标操作的Mapper.java与Mapper.xml,极大地提高了开发速度。
1.jar包
2.配置文件
需要修改数据库连接信息,mapper生成目录与pojo生成位置,也要修改要导出的表。
工程目录下配置generatorConfig.xml
<?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> <context id="testTables" targetRuntime="MyBatis3"> <commentGenerator> <!-- 是否去除自动生成的注释 true:是 : false:否 --> <property name="suppressAllComments" value="true" /> </commentGenerator> <!--数据库连接的信息:驱动类、连接地址、用户名、密码 --> <jdbcConnection driverClass="com.mysql.jdbc.Driver" connectionURL="jdbc:mysql://localhost:3306/exam" userId="root" password="123456"> </jdbcConnection> <!-- <jdbcConnection driverClass="oracle.jdbc.OracleDriver" connectionURL="jdbc:oracle:thin:@127.0.0.1:1521:yycg" userId="yycg" password="yycg"> </jdbcConnection> --> <!-- 默认false,把JDBC DECIMAL 和 NUMERIC 类型解析为 Integer,为 true时把JDBC DECIMAL 和 NUMERIC 类型解析为java.math.BigDecimal --> <javaTypeResolver> <property name="forceBigDecimals" value="false" /> </javaTypeResolver> <!-- targetProject:生成PO类的位置 --> <javaModelGenerator targetPackage="cn.xm.pojo" targetProject=".\src"> <!-- enableSubPackages:是否让schema作为包的后缀 --> <property name="enableSubPackages" value="false" /> <!-- 从数据库返回的值被清理前后的空格 --> <property name="trimStrings" value="true" /> </javaModelGenerator> <!-- targetProject:mapper映射文件生成的位置 --> <sqlMapGenerator targetPackage="cn.xm.mapper" targetProject=".\src"> <!-- enableSubPackages:是否让schema作为包的后缀 --> <property name="enableSubPackages" value="false" /> </sqlMapGenerator> <!-- targetPackage:mapper接口生成的位置 --> <javaClientGenerator type="XMLMAPPER" targetPackage="cn.xm.mapper" targetProject=".\src"> <!-- enableSubPackages:是否让schema作为包的后缀 --> <property name="enableSubPackages" value="false" /> </javaClientGenerator> <!-- 指定数据库表 --> <table tableName="blacklist"></table> <table tableName="breakrules"></table> <table tableName="checkrecord"></table> <table tableName="department"></table> <table tableName="dictionary"></table> <table tableName="employee_in"></table> <table tableName="employee_out"></table> <table tableName="employeeexam"></table> <table tableName="exam"></table> <table tableName="exampaper"></table> <table tableName="historypaperoption"></table> <table tableName="historypaperquestion"></table> <table tableName="newsrecord"></table> <table tableName="onlineexamanswerinfor"></table> <table tableName="onlineexaminfor"></table> <table tableName="options"></table> <table tableName="permission"></table> <table tableName="pictureindex"></table> <table tableName="project"></table> <table tableName="questionbank"></table> <table tableName="questions"></table> <table tableName="role"></table> <table tableName="rolepermission"></table> <table tableName="traincontent"></table> <table tableName="unit"></table> <table tableName="unitproject"></table> <table tableName="userrole"></table> </context> </generatorConfiguration>
3. Java程序
1 package mybatisInverse; 2 import java.io.File; 3 import java.util.ArrayList; 4 import java.util.List; 5 import org.mybatis.generator.api.MyBatisGenerator; 6 import org.mybatis.generator.config.Configuration; 7 import org.mybatis.generator.config.xml.ConfigurationParser; 8 import org.mybatis.generator.internal.DefaultShellCallback; 9 10 public class GeneratorSqlmap 11 { 12 public void generator() 13 throws Exception 14 { 15 List<String> warnings = new ArrayList(); 16 boolean overwrite = true; 17 18 File configFile = new File("generatorConfig.xml"); 19 ConfigurationParser cp = new ConfigurationParser(warnings); 20 Configuration config = cp.parseConfiguration(configFile); 21 DefaultShellCallback callback = new DefaultShellCallback(overwrite); 22 MyBatisGenerator myBatisGenerator = new MyBatisGenerator(config, 23 callback, warnings); 24 myBatisGenerator.generate(null); 25 } 26 27 public static void main(String[] args) 28 throws Exception 29 { 30 try 31 { 32 GeneratorSqlmap generatorSqlmap = new GeneratorSqlmap(); 33 generatorSqlmap.generator(); 34 } 35 catch (Exception e) 36 { 37 e.printStackTrace(); 38 } 39 } 40 }
运行结果:
4.使用生成的代码:
对单表操作较方便,可以自定义条件查询。
sqlMapConfig.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> <!-- 加载属性文件 --> <properties resource="db.properties"> <!--properties中还可以配置一些属性名和属性值 --> <!-- <property name="jdbc.driver" value=""/> --> </properties> <!-- 全局配置参数,需要时再设置 --> <!-- <settings> </settings> --> <!-- 别名定义 --> <typeAliases> <!-- 针对单个别名定义 type:类型的路径 alias:别名 --> <!-- <typeAlias type="cn.itcast.mybatis.po.User" alias="user"/> --> <!-- 批量别名定义 指定包名,mybatis自动扫描包中的po类,自动定义别名,别名就是类名(首字母大写或小写都可以) --> <package name="cn.xm.pojo"/> </typeAliases> <!-- 和spring整合后 environments配置将废除--> <environments default="development"> <environment id="development"> <!-- 使用jdbc事务管理,事务控制由mybatis--> <transactionManager type="JDBC" /> <!-- 数据库连接池,由mybatis管理--> <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> <!-- 加载 映射文件 --> <mappers> <!--通过resource方法一次加载一个映射文件 --> <!-- <mapper resource="mapper/UserMapper.xml"/> --> <!-- 通过mapper接口加载单个 映射文件 遵循一些规范:需要将mapper接口类名和mapper.xml映射文件名称保持一致,且在一个目录 中 上边规范的前提是:使用的是mapper代理方法 --> <!-- <mapper class="cn.itcast.mybatis.mapper.UserMapper"/> --> <!-- 批量加载mapper 指定mapper接口的包名,mybatis自动扫描包下边所有mapper接口进行加载 遵循一些规范:需要将mapper接口类名和mapper.xml映射文件名称保持一致,且在一个目录 中 上边规范的前提是:使用的是mapper代理方法 --> <package name="cn.xm.mapper"/> </mappers> </configuration>
java代码:
package cn.xm.test; import java.io.InputStream; import java.net.URL; import java.util.Date; 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 org.apache.tomcat.jdbc.pool.interceptor.SlowQueryReportJmxMBean; import org.junit.Before; import org.junit.Test; import cn.xm.mapper.EmployeeInMapper; import cn.xm.pojo.EmployeeIn; import cn.xm.pojo.EmployeeInExample; public class MybatisTest { private SqlSessionFactory sqlSessionFactory; @Before public void setUp() throws Exception { // 将全局配置文件作为一个流 String resource = "sqlMapConfig.xml"; URL realPath2 = Resources.getResourceURL("sqlMapConfig.xml"); InputStream inputStream = Resources.getResourceAsStream(resource); // 建立一个SqlSession工厂 sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream); } // 测试增加 @Test public void testAdd() throws Exception { SqlSession sqlSession = sqlSessionFactory.openSession(); EmployeeInMapper eim = sqlSession.getMapper(EmployeeInMapper.class); EmployeeIn sl = new EmployeeIn(); sl.setIdcode("33"); sl.setEmployeeid("3"); sl.setEmployeenumber("3"); sl.setPassword("33333"); ; sl.setName("王五"); eim.insert(sl); sqlSession.commit(); sqlSession.close(); } // 测试删除 @Test public void testDeleteById() throws Exception { SqlSession sqlSession = sqlSessionFactory.openSession(); EmployeeInMapper eim = sqlSession.getMapper(EmployeeInMapper.class); eim.deleteByPrimaryKey("3"); sqlSession.commit(); sqlSession.close(); } // 测试修改 @Test public void fun2() throws Exception { SqlSession sqlSession = sqlSessionFactory.openSession(); EmployeeInMapper eim = sqlSession.getMapper(EmployeeInMapper.class); EmployeeIn selectByPrimaryKey = eim.selectByPrimaryKey("3"); selectByPrimaryKey.setName("这是修改后的值"); eim.updateByPrimaryKey(selectByPrimaryKey); sqlSession.commit(); sqlSession.close(); } // 测试通过id查询单个 @Test public void fun3() throws Exception { SqlSession sqlSession = sqlSessionFactory.openSession(); EmployeeInMapper eim = sqlSession.getMapper(EmployeeInMapper.class); EmployeeIn selectByPrimaryKey = eim.selectByPrimaryKey("3"); System.out.println(selectByPrimaryKey); } // 自定义条件查询 查询名字为张三的 @Test public void testSelectByExample() { SqlSession sqlSession = sqlSessionFactory.openSession(); EmployeeInMapper eim = sqlSession.getMapper(EmployeeInMapper.class); EmployeeInExample employeeInExample = new EmployeeInExample(); // 通过criteria构造查询条件 EmployeeInExample.Criteria criteria = employeeInExample.createCriteria(); criteria.andNameEqualTo("张三"); // 可能返回多条记录 List<EmployeeIn> list = eim.selectByExample(employeeInExample); System.out.println(list); } // 自定义条件查询 查询名字为张三的且password为44444的 @Test public void testSelectByExample1() { SqlSession sqlSession = sqlSessionFactory.openSession(); EmployeeInMapper eim = sqlSession.getMapper(EmployeeInMapper.class); EmployeeInExample employeeInExample = new EmployeeInExample(); // 通过criteria构造查询条件 EmployeeInExample.Criteria criteria = employeeInExample.createCriteria(); criteria.andNameEqualTo("张三"); criteria.andPasswordEqualTo("44444"); // 可能返回多条记录 List<EmployeeIn> list = eim.selectByExample(employeeInExample); System.out.println(list); } // 自定义条件查询 查询所有,只是不封装条件 @Test public void testSelectByExample3() { SqlSession sqlSession = sqlSessionFactory.openSession(); EmployeeInMapper eim = sqlSession.getMapper(EmployeeInMapper.class); EmployeeInExample employeeInExample = new EmployeeInExample(); // 通过criteria构造查询条件 EmployeeInExample.Criteria criteria = employeeInExample.createCriteria(); // 可能返回多条记录 List<EmployeeIn> list = eim.selectByExample(employeeInExample); System.out.println(list); } }
时间: 2024-10-10 01:54:03