package com.ljs.dao;import java.sql.Connection;
import java.util.ArrayList;
import java.util.List;import org.apache.commons.dbutils.QueryRunner;
import org.apache.commons.dbutils.handlers.BeanHandler;
import org.apache.commons.dbutils.handlers.BeanListHandler;
import org.apache.commons.dbutils.handlers.ScalarHandler;import com.ljs.util.JDBCUtil;public class DBUtilDao{QueryRunner qRunner = new QueryRunner();Connection connection = null;/**  查询多条结果。*/public<T> List<T> queryMutil(Class<T> clazz, String sql, Object...object){List<T> list = new ArrayList<>();try {connection = JDBCUtil.getConn();list = qRunner.query(connection, sql,new BeanListHandler<T>(clazz),object);}catch (Exception e) {e.printStackTrace();}finally {JDBCUtil.close(null, null, connection);}return list;}/**  查询一条结果。*/public<T> T queryOne(Class<T> clazz, String sql, Object...objects){try {connection = JDBCUtil.getConn();T t = clazz.newInstance();t = qRunner.query(connection, sql, new BeanHandler<T>(clazz), objects);return t; } catch (Exception e) {e.printStackTrace();}return null;}/** 更新表*/public<T> void update(String sql, Object...objects){try {connection = JDBCUtil.getConn();qRunner.update(connection, sql, objects);} catch (Exception e) {e.printStackTrace();}}/** 查询某个数scalar*/public String scalar(String sql, Object...objects){try {connection = JDBCUtil.getConn();return qRunner.query(connection, sql,new ScalarHandler<>(), objects).toString();} catch (Exception e) {e.printStackTrace();}return null;}}