用户登录只有第一条数据成功，只能查询到第一条数据

用户登录只有第一条数据成功，只能查询到第一条数据：实现用户登录功能。

四条数据，只有第一条可登陆成功

原因是：

	sql = "select*from manager";

应为

	sql = "select*from manager where username='"+username+"'and password='"+password+"'";

response.setContentType("test/html;charset=utf-8");
		response.setCharacterEncoding("utf-8");
		// 获取jsp中填入数据
		String username = request.getParameter("username");
		String password = request.getParameter("password");
		// 数据库相关
		String Dusername = null;
		String Dpassword = null;
		int Did = 0;
		String sql = null;
		// 与数据库建立连接
		try {
			Class.forName("com.mysql.jdbc.Driver");
			System.out.println("Loading Database success");
		} catch (Exception e) {
			System.out.println("Class not found exception");
		}
		String url = "jdbc:mysql://localhost:3306/Creation";
		Connection con = null;
		Statement stmt = null;
		ResultSet rs = null;

		try {
			con = (Connection) DriverManager.getConnection(url, "root", "");
			stmt = (Statement) con.createStatement();

			sql = "select*from manager where username='"+username+"'and password='"+password+"'";
			rs = stmt.executeQuery(sql);
			while (rs.next()) {
				// 因为不止一个数据，就要循环，对每条数据都进行验证匹配
					Dusername = rs.getString("username");
					Dpassword = rs.getString("password");
					System.out.println(Dusername);
					System.out.println(Dpassword);
					if (username.equals(Dusername) && password.equals(Dpassword)) {
						System.out.println("manager登陆成功");
						// 要成功，跳转success.jsp
						response.sendRedirect("success.jsp");
						
						}
					else if (username.equals("admin") && password.equals("admin")) {
						System.out.println("super manager登陆成功");
						// 要成功，跳转success.jsp
						response.sendRedirect("manager.jsp");
						return;
						}
					else {
						System.out.println("登陆失败");
						response.sendRedirect("fail.jsp");
						return;
						}
				}
		} catch (Exception e) {
			e.printStackTrace();
		}
	}