我目前正在java eclipse IDE上做一个项目。我有一个servlet,显示密码更改功能。正如您所看到的,我根据用户输入编程返回的各种错误,例如: “密码不匹配”。但是,它始终打印在屏幕顶部。有什么办法可以将这些错误输出为实际的格式错误吗?也许以弹出框的形式或至少将其放置在适当的位置?
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
import java.sql.*;
public class NewPassword extends HttpServlet {
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("text/html;charset=UTF-8");
PrintWriter out = response.getWriter();
String oldpassword = request.getParameter("oldpassword");
String newpassword = request.getParameter("newpassword");
String confirmpassword = request.getParameter("confirmpassword");
int newpass = newpassword.length();
HttpSession session = request.getSession(false);
String employeeid = "";
if(session != null) {
employeeid = (String)session.getAttribute("employeeid");
}
boolean st = false;
try {
Class.forName("com.mysql.jdbc.Driver").newInstance();
Connection con = DriverManager.getConnection("jdbc:mysql://localhost:3306/payroll_system", "root", "");
PreparedStatement ps = con.prepareStatement("SELECT pwd FROM payroll_system.employee_login WHERE employeeID = ?");
ps.setString(1, employeeid);
ResultSet rs = ps.executeQuery();
st = rs.next();
String currentpassword = rs.getString("pwd");
if(st) {
if((currentpassword.equals(oldpassword)) && newpassword.equals(confirmpassword) && newpass >= 8) {
PreparedStatement pd = con.prepareStatement("UPDATE payroll_system.employee_login SET pwd = ? where employeeID = ?" );
pd.setString(1, newpassword);
pd.setString(2, employeeid);
int updated = pd.executeUpdate();
if(updated > 0){
out.println("Password Successfully Updated");
RequestDispatcher rd = request.getRequestDispatcher("changePassAdmin.html");
rd.include(request, response);
}
}
else if(oldpassword.equals("") || newpassword.equals("") || confirmpassword.equals("") ) {
out.println("Fields cannot be left blank.");
RequestDispatcher rd = request.getRequestDispatcher("changePassAdmin.html");
rd.include(request, response);
}
else if(!currentpassword.equals(oldpassword) && !newpassword.equals(confirmpassword)) {
out.println("Old password is incorrect and passwords do not match, please try again.");
RequestDispatcher rd = request.getRequestDispatcher("changePassAdmin.html");
rd.include(request, response);
}
else if(!currentpassword.equals(oldpassword)) {
out.println("Old password entered incorrectly, please try again.");
RequestDispatcher rd = request.getRequestDispatcher("changePassAdmin.html");
rd.include(request, response);
}
else if(!newpassword.equals(confirmpassword)) {
out.println("Passwords do not match, please try again.");
RequestDispatcher rd = request.getRequestDispatcher("changePassAdmin.html");
rd.include(request, response);
}
else if(newpass < 8 ) {
out.println("New Password must be atleast 8 characters in length.");
RequestDispatcher rd = request.getRequestDispatcher("changePassAdmin.html");
rd.include(request, response);
}
}
}catch(Exception e)
{
e.printStackTrace();
}
out.close();
}
}
答案 0 :(得分:1)
你可以使用ajax和js来处理错误。使用ajax与服务器通信,当得到错误时,使用js函数显示一个对话框。这只是一个解决方案。你可以试试这个。
答案 1 :(得分:1)
您可以将spring-form标签与bean验证一起使用。
例如,在jsp中,您可以显示特定字段的错误:
C
答案 2 :(得分:0)
您可以使用log4j之类的日志框架。例如,在Log4j中,有记录器,追加器和布局。借助布局,您可以设计自己的错误消息的格式。