首先，webxml中配置listener，並配置配置文件的路徑作爲參數
<!-- 初始化mybatis配置文件路徑 --> <context-param> <param-name>mybatisConfigLocation</param-name> <param-value>com/config/configuration.xml</param-value> </context-param> <!-- 初始化SessionFactory監聽器 --> <listener> <listener-class>com.mybatis.listener.MybatisLoaderListener</listener-class> </listener>
第二步：
定義MybatisLoaderListener和MybatisLoader類，MybatisLoaderListener繼承自MybatisLoader並且實現接口ServletContextListener
MybatisLoaderListener的代碼如下：
package com.mybatis.listener;
import javax.servlet.ServletContextEvent;
import javax.servlet.ServletContextListener;
import org.apache.log4j.Logger;
public class MybatisLoaderListener extends MybatisLoader implements ServletContextListener {
private static final Logger log = Logger.getLogger(MybatisLoaderListener.class);
@Override
public void contextDestroyed(ServletContextEvent arg0) {
}
@Override
public void contextInitialized(ServletContextEvent event) {
log.info("init mybatis configuration start ...");
initSqlSessionFatory(event.getServletContext());
log.info("init mybatis configuration success.");
}
}MybatisLoader代碼如下：
package com.mybatis.listener;
import java.io.File;
import java.io.FileReader;
import java.io.IOException;
import java.io.Reader;
import javax.servlet.ServletContext;
import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;
import org.apache.log4j.Logger;
public class MybatisLoader {
private static final Logger log = Logger.getLogger(MybatisLoader.class);
public static final String MYBATIS_CONFIG_LOCATION = "mybatisConfigLocation";
//sql會話工廠
private static SqlSessionFactory sqlSessionFactory = null;
public static SqlSessionFactory getSqlSessionFactory(){
return sqlSessionFactory;
}
public void initSqlSessionFatory(ServletContext servletContext) {
String configurationXml=servletContext.getInitParameter(MYBATIS_CONFIG_LOCATION);
try {
if(sqlSessionFactory == null){
//使用項目src路徑（如果配置文件放到src目錄下，使用以下代碼加載）
Reader reader = Resources.getResourceAsReader(configurationXml);
sqlSessionFactory = new SqlSessionFactoryBuilder().build(reader);
log.debug("init sqlSessionFactory success");
//使用絕對路徑(如果配置文件放到WEB-INF目錄下，使用以下代碼加載)
//Reader reader = new FileReader(servletContext.getRealPath(configurationXml));
//sqlSessionFactory = new SqlSessionFactoryBuilder().build(reader);
}
} catch (IOException ioex) {
throw new RuntimeException("Get resource error:"+configurationXml, ioex);
}
}
}第三步：在Dao中使用
SqlSessionFactory sqlSessionFactory=MybatisLoader.getSqlSessionFactory();
SqlSession sqlSession = sqlSessionFactory.openSession();
List list = sqlSession.selectList("com.foo.bean.BlogMapper.queryAllBlogInfo");特別說明：
如果配置文件放到WEB-INF目錄下，必須使用絕對路徑去獲取Reader,org.mybatis.io.Resources本身不不支持將配置文件放置到WEB-INF目錄下；
舉例
<!-- 初始化mybatis配置文件路徑 -->
<context-param> <param-name>mybatisConfigLocation</param-name> <param-value>/WEB-INF/configuration.xml</param-value> </context-param>
在MybatisLoader的方法initSqlSessionFatory中使用
Reader reader = new FileReader(servletContext.getRealPath(configurationXml)); sqlSessionFactory = new SqlSessionFactoryBuilder().build(reader);