连接数据库

import com.mchange.v2.c3p0.ComboPooledDataSource;import javax.sql.DataSource;import java.sql.Connection;import java.sql.SQLException;/*** JDBC操作的工具类* Created by yangrb on 17-6-21.*/public class JdbcUtils {/*** 释放connection* @param connection*/public static void releaseConnection(Connection connection){try {if (connection!=null){connection.close();}} catch (SQLException e) {e.printStackTrace();}}private static DataSource dataSource = null;/*** 数据源只能创建一次.故不能多次创建*/static{dataSource = new ComboPooledDataSource("mvcapp");}/*** 返回数据源的一个Connection对象* @return*/public static Connection getConnection() throws SQLException{return dataSource.getConnection();}}

利用QueryRunner进行操作

private QueryRunner queryRunner = new QueryRunner();Connection connection = null;try {connection = JdbcUtils.getConnection();return (E) queryRunner.query(connection,sql,new ScalarHandler(),args);}catch (Exception e){e.printStackTrace();}finally {JdbcUtils.releaseConnection(connection);}