iBatis3尝鲜

最新推荐文章于 2022-12-01 14:56:11 发布

原创最新推荐文章于 2022-12-01 14:56:11 发布 · 2.4k 阅读

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文章标签：

#ibatis #string #encoding #exception #interface #session

本文介绍如何使用iBatis3进行数据库操作，包括配置文件、SqlMap文件编写、工具类设计、JavaBean定义及测试程序运行。同时展示了通过接口和元注释方式定义SqlMapper的方法。

1.准备配置文件:

<?xml version="1.0" encoding="UTF-8" ?> <!DOCTYPE configuration PUBLIC "-//ibatis.apache.org//DTD Config 3.0//EN" "http://ibatis.apache.org/dtd/ibatis-3-config.dtd"> <configuration> <environments default="development"> <environment id="development"> <transactionManager type="JDBC"/> <dataSource type="UNPOOLED"> <property name="driver" value="..."/> <property name="url" value="..."/> <property name="username" value="..."/> <property name="password" value="..."/> </dataSource> </environment> </environments> <mappers> <mapper resource="NewsMapper.xml"/> </mappers> </configuration>

2.准备SqlMap文件:

<?xml version="1.0" encoding="UTF-8" ?> <!DOCTYPE mapper PUBLIC "-//ibatis.apache.org//DTD Mapper 3.0//EN" "http://ibatis.apache.org/dtd/ibatis-3-mapper.dtd"> <mapper namespace="News"> <select id="selectNews" parameterType="string" resultType="ibatis3.News"> select news_full_title as title from news where news_id = #{id} </select> </mapper>

3.编写一个工具类:

public class IBatisUtil { private static SqlSessionFactory sqlMapper; private IBatisUtil()throws Exception{ } public static SqlSession openSession()throws Exception{ if(sqlMapper==null){ String resource = "configuration.xml"; Reader reader = Resources.getResourceAsReader(resource); sqlMapper = new SqlSessionFactoryBuilder().build(reader); } return sqlMapper.openSession(); } }

4.准备JavaBean:

public class News { private String title; public String getTitle() { return title; } public void setTitle(String title) { this.title = title; } }

5.测试程序:

SqlSession session=IBatisUtil.openSession(); News news=(News)session.selectOne("News.selectNews","9E045EA1-6E77-483E-8771-0004BC737DAD"); System.out.println(news.getTitle()); session.close();

iBatis3还支持通过interface+元注释的方式定义SqlMapper。修改NewsMapper.xml:

编写NewsMapper接口:

public interface NewsMapper { @Select("SELECT news_full_title as title FROM news WHERE news_id = #{id}") News selectNews(String id); }

修改测试代码:

SqlSession session=IBatisUtil.openSession(); NewsMapper mapper = session.getMapper(NewsMapper.class); News news= mapper.selectNews("9E045EA1-6E77-483E-8771-0004BC737DAD"); System.out.println(news.getTitle()); session.close();