MyBatis学习存档（1）——入门

CREATE DATABASE test;
USE test;
CREATE TABLE users(id INT PRIMARY KEY identity(1,1), name VARCHAR(20), password VARCHAR(20));
INSERT INTO users(name, password) VALUES (‘aaa‘, ‘123‘);
INSERT INTO users(name, password) VALUES (‘bbb‘, ‘456‘);

<?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.microsoft.sqlserver.jdbc.SQLServerDriver"
            connectionURL="jdbc:sqlserver://127.0.0.1:1433;DatabaseName=test" userId="sa"
            password="123456">
        </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:生成实体类的位置 -->
        <javaModelGenerator targetPackage="com.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="com.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="com.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="users"  selectByExampleQueryId="false" enableUpdateByExample="false" enableDeleteByExample="false" enableSelectByExample="false" enableCountByExample="false" ></table>
    
    </context>
</generatorConfiguration>

package com.util;

import java.io.File;
import java.util.ArrayList;
import java.util.List;

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;

public class Build {
    public static void main(String[] args) throws Exception {

        List<String> warnings = new ArrayList<String>();
        boolean overwrite = true;
        //映射配置文件
        File configFile = new File("generatorConfig.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);  
        System.out.println("映射完成");
        
    }
}

<?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>

      <properties resource="database.properties"></properties>
      
      <settings>
          <!-- 开启二级缓存总开关 -->
          <setting name="cacheEnabled" value="true"/>
          <!--设置懒 加载 -->
        <setting name="lazyLoadingEnabled" value="true"/>
        <!-- 积极加载设置  不积极＝＝懒 -->
          <setting name="aggressiveLazyLoading" value="false"/>
          <!-- 设置自动装配形式  -->
          <setting name="autoMappingBehavior" value="FULL"/>
      </settings>
      
      <!-- 起别名 -->
      <typeAliases>
          <package name="com.pojo"/>
      </typeAliases>
      
    　<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>
        <package name="com.mapper"/>
      </mappers>
      
</configuration>

jdbc.driver=com.microsoft.sqlserver.jdbc.SQLServerDriver
jdbc.url=jdbc:sqlserver://127.0.0.1:1433;DatabaseName=test
jdbc.username=sa
jdbc.password=123456

package com.test;

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;

import com.pojo.Users;

public class Test1 {
    
    public static void main(String[] args) throws Exception {
        //mybatis的核心配置文件
        String resource = "mybatis-config.xml";
        //使用MyBatis提供的Resources类加载mybatis的配置文件
        InputStream  is = Resources.getResourceAsStream(resource);
        //构建SqlSession的工厂
        SqlSessionFactory factory = new SqlSessionFactoryBuilder().build(is);
        //开启SqlSession
        SqlSession session = factory.openSession();
        String statement = "com.mapper.UsersMapper.selectByPrimaryKey";//映射sql的标识字符串
        //执行查询
        Users user = session.selectOne(statement, 1);
        //输出结果
        System.out.println(user.getName() + "=======" + user.getPassword());
    }

}