login.jsp

数据结构考试 网站（jsp）

<%@ page language="java" pageEncoding="UTF-8"%>
<%@ page import="java.sql.*"%>

<%
	// 获取提交的用户名：
	String username = request.getParameter("username");
	// 获取提交的密码：
	String password = request.getParameter("password");

	try {
			String driverName="com.mysql.jdbc.Driver";      //驱动程序名
			String userName="root";                         //数据库用户名
			String userPwd="root";                        //密码
		    String dbName="dstester";                        //数据库名
		    String url="jdbc:mysql://localhost/"+dbName+
		                    "?user="+userName+"&password="+userPwd;    //连接字符串
		    Connection conn = null;                          //数据库连接对象
		    Statement stmt = null;                               //数据库语句对象
		    ResultSet rs = null;
		    // 建立数据库连接

	    	 try {
	    		 Class.forName(driverName).newInstance();
	        	 conn=DriverManager.getConnection(url);  //获得数据库连接
	        	 stmt=conn.createStatement();
	         } catch(Exception e) {
	    		 e.printStackTrace();		 
	        	 out.print("数据库连接失败!");
	    	 }
				
			rs = stmt.executeQuery("select *from admin where username='"+ username + "' and password='" + password + "'");
			//System.out.print("select *from admin where username='"+ username + "' and password='" + password + "'");
			//rs = stmt.executeQuery("select *from admin");
			//String name = null;
			//while(rs.next())
			 	//name = rs.getString(1);

			if (rs.next()) {
				try {
					response.sendRedirect("check.jsp");
				} catch (Exception e) {
					System.out.println("抛出异常:  "+e.getMessage());
				}
			} else {
				// 否则（记录集为空），表明失败：
				request.setAttribute("error", "用户名与密码不匹配,登录失败,请重试！");
				try {
					request.getRequestDispatcher("index.jsp").forward(request,
							response);
				} catch (Exception e) {
					System.out.println("抛出异常:  "+e.getMessage());
				}
			}
			//rs.close();
			//stmt.close();
			//conn.close();
			try {
				if (stmt != null) {
					stmt.close();
				}
				conn.close();
			} catch (SQLException SqlE) {
				SqlE.printStackTrace();
				out.print("数据库关闭失败！");
			}

		} catch (Exception e) {
			System.out.println("抛出异常:  "+e.getMessage());
		}
%>