Anmeldeformular mit Ajax und Ruhezustand ⇐ Java

[Anonymous]

Ich versuche, das Anmeldeformular mit einer Datenbank zu verbinden.Wenn man einen falschen Benutzernamen eingibt, sollte Ajax die Antwort zurückgeben:

"falscher Benutzername".

Mein Servlet ist mit dem Ruhezustand verbunden, sodass ich Benutzernamen aus der Datenbank mit HPQL überprüfen kann. Ohne Ruhezustandscode sendet mein Servlet ohne Probleme eine Zeichenfolge an mich zurück, aber mit Ruhezustandscode kann Ajax keine Antwort zurücksenden, wenn ich versuche zu überprüfen, ob der Benutzername vorhanden ist.
Meine index.html

Code: Select all

pokusaj 2




function check(){
var username=document.getElementById("username").value;
var password=document.getElementById("password").value;

$.post("servletprovera", {"username":username, "password":password},
function(data){
document.getElementById("alert").innerHTML=data.result;
});//servletprovera is URL of my servlet
}








[/b]

mein Servlet

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@WebServlet(name = "ServletProvera", urlPatterns = {"/servletprovera"})
public class ServletProvera extends HttpServlet {

/**
* Processes requests for both HTTP GET

and

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POST

* methods.
*
* @param request servlet request
* @param response servlet response
* @throws ServletException if a servlet-specific error occurs
* @throws IOException if an I/O error occurs
*/
protected void processRequest(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("application/json");
String user=request.getParameter("username");

Configuration myConf=new Configuration();
myConf.configure("hibernate.cfg.xml");
StandardServiceRegistry service=new StandardServiceRegistryBuilder().
applySettings(myConf.getProperties()).build();
SessionFactory myFactory=myConf.buildSessionFactory(service);
Session conn=myFactory.openSession();
Transaction t=conn.beginTransaction();
List list;//Korisniciajax-Hibernate_entity class
list=conn.createQuery("k FROM Korisniciajax k WHERE k.korUser=\""+user+"\"").list();

t.commit();
conn.close();

String result;

if(list==null){
result="wrong username";
}
else {
result="success";
}

try (PrintWriter out = response.getWriter()) {
/* TODO output your page here. You may use following sample code. */
out.print("{\"result\":\""+result+"\"}");
}

}

//
/**
* Handles the HTTP

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GET

method.
*
* @param request servlet request
* @param response servlet response
* @throws ServletException if a servlet-specific error occurs
* @throws IOException if an I/O error occurs
*/
@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
processRequest(request, response);
}

/**
* Handles the HTTP

Code: Select all

POST

method.
*
* @param request servlet request
* @param response servlet response
* @throws ServletException if a servlet-specific error occurs
* @throws IOException if an I/O error occurs
*/
@Override
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
processRequest(request, response);
}

/**
* Returns a short description of the servlet.
*
* @return a String containing servlet description
*/
@Override
public String getServletInfo() {
return "Short description";
}//

}