mybatis环境搭建步骤
1、导入Jar包:mybatis核心包
2、在src文件夹下新建config文件夹,在config文件夹中新建mybatis核心配置文件“mybatis.xml”
“mybatis.xml”文件模板:http://www.mybatis.org/mybatis-3/zh/getting-started.html:从 XML 中构建 SqlSessionFactory
<?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>
<environments default="development">
<environment id="development">
<transactionManager type="JDBC"/>
<dataSource type="POOLED">
<property name="driver" value="${driver}"/>
<property name="url" value="${url}"/>
<property name="username" value="${username}"/>
<property name="password" value="${password}"/>
</dataSource>
</environment>
</environments>
<mappers>
<mapper resource="org/mybatis/example/BlogMapper.xml”/>//resource中填写“×××Mapper.xml”文件的文件名
</mappers>
</configuration>
实例1:
<?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>
<environments default="development">
<environment id="development">
<transactionManager type="JDBC" />
<dataSource type="POOLED">
<property name="driver" value="oracle.jdbc.driver.OracleDriver" />
<property name="url" value="jdbc:oracle:thin:@192.168.1.188:1521:ORCL" />
<property name="username" value="scott" />
<property name="password" value="tiger" />
</dataSource>
</environment>
</environments>
<mappers>
<!-- mybatis的配置文件 -->
<mapper resource="dao/NewsMapper.xml" />
</mappers>
</configuration>
实例2:
保留“mybatis.xml”文件默认内容,在config文件夹下新建oracle.properties文件
文件中写入:
driver=oracle.jdbc.driver.OracleDriver
url=jdbc:oracle:thin:@192.168.1.188:1521:ORCL
username=scott
password=tiger
3、在src文件下新建dao包,新建“×××Mapper.java”接口文件
接口文件中为增删改查的抽象方法
在src文件下新建“×××Mapper.xml”文件,规范上和“×××Mapper.java”接口文件同名
“×××Mapper.xml”文件模板:http://www.mybatis.org/mybatis-3/zh/getting-started.html:探究已映射的 SQL 语句
<?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="org.mybatis.example.BlogMapper”>//namespace中填写”×××Mapper.java“文件的包名+类名
实例:
<?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="dao.NewsMapper">
<resultMap id="news" type="model.News”>//返回对象映射:id值为映射名称(自定义),和select语句中的resultMap值相同,type值为返回对象类型的包名+类名
<result column="newsid" property="newsID" />//column值为数据库字段名称,property值为返回对象类型的属性名称,将数据库中newsid字段的查询结果赋值给返回对象类型的newsID属性
<result column="newstopic" property="topic" />
<result column="newsauthor" property="author" />
<result column="newscreatetime" property="createTime" />
<result column="newsgrade" property="grade" />
<result column="newscontent" property="content" />
<result column="newspic" property="pic" />
</resultMap>
<insert id="addNews" parameterType="model.News”>
insert into nmsnews
values(#{newsID},#{author},#{createTime},#{topic},#{grade},#{content},#{pic})
</insert>//id值为“×××.java”接口文件中的对应抽象方法名,parameterType值为传入参数对象类型的包名+类名
<select id="queryAllOwnNews" parameterType="String" resultMap="news">
select * from nmsnews where newsauthor=#{author}
</select>
<select id="queryNews" parameterType="model.News" resultMap="news">
select * from nmsnews where newsauthor=#{author}
<if test="newsID!= null and newsID!=''">
and newsID like #{newsID}
</if>
<if test="createTime!=null and createTime!=''">
and newscreateTime like #{createTime}
</if>
<if test="topic!= null and topic!=''">
and newstopic like #{topic}
</if>
<if test="grade!= null and grade!=''">
and newsgrade=#{grade}
</if>
</select>
<update id="updateNews" parameterType="model.News">
update nmsnews set
newsauthor=#{author},newscreatetime=#{createTime},newstopic=#{topic},newsgrade=#{grade},newscontent=#{content},newspic=#{pic}
where newsid=#{newsID}
</update>
<delete id="deleteNews" parameterType="String">
delete from nmsnews
where
newsid=#{newsID}
</delete>
</mapper>
4、在src文件下新建dao包util包,新建“sqlSessionUtil.java”文件
文件中写入:
package util;
import java.io.IOException;
import java.io.Reader;
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 SqlSessionUtil {
private static SqlSessionFactory factory;
static {
try {
Reader reader = Resources.getResourceAsReader("mybatis.xml");//参数值为mybatis核心配置文件“mybatis.xml”文件名
factory = new SqlSessionFactoryBuilder().build(reader);
} catch (IOException e) {
e.printStackTrace();
}
}
public static SqlSession getSession() {
return factory.openSession();
}
}