数据库连接池

<span>计算确定数据表一共分几页：
	101/pageSize=100/10=10页。
	rows = select count(1) from users;
	方法１：pageCount = rows/pageSize + (rows%pageSize==0?0:1);
　　方法２：pageCount = (rows+ (pageSize-1))/(pageSize);
public void doGet(HttpServletRequest req, HttpServletResponse response)
			throws ServletException, IOException {
		//第一步：定义每页显示多少行
		int pageSize = 10;
		try{
			//第二步：获取数据表中有多少行
			QueryRunner run = new QueryRunner(DataSourceUtils.getDatasSource());
			String sql = "select count(*) from users";
			Object o = run.query(sql,new ScalarHandler());
			int rows = Integer.parseInt(o.toString());
			//第三步：计算一共分多少页
			int pageCount= rows/pageSize+(rows%pageSize==0?0:1);
			//将页数放到req
			req.setAttribute("pageCount",pageCount);
			
		}catch(Exception e){
			e.printStackTrace();
		}
		//转发到
		req.getRequestDispatcher("/jsps/show.jsp").forward(req, response);
		
	}
</span>