I try to validate a field with ajax and a function which verify that the value is not already in base.
All examples I found are with php ; how to do with java ?
JSP code :
<form id="FLoginNew" action="Loginnew" method="post">
.....
<script>
$(document).ready(function(e) {
$("#FLoginNew").validationEngine('attach', {promptPosition : "centerRight", scroll: false, validationEventTrigger: "blur", autoHidePrompt:true, autoHideDelay:3000 });
});
</script>
jquery.ValidationEngine-fr.js altered :
"ajaxLoginCall": {
"url": "myapp.selvlets.DoublonLoginServlet",
"extraDataDynamic": ['#login'],
"alertText": "* Ce login est déjà pris",
"alertTextOk": "* Ce login est disponible",
"alertTextLoad": "* Chargement, veuillez attendre"
},
As URL, I tried : "url": "/DoublonLogin", which is the declaration of the servlet mapping in web.xml.
I don't know what to put as url...
Thank you !
I'm answering myself : I found the solution :
ReplyDeleteAt first, the input class (I didn't display) : class="validate[required,ajax[Ajaxdoublonlogin]]"
Then, the url of the Ajax call called "Ajaxdoublonlogin" : "Doublonlogin" as it is declared in the web.xml file. It's a servlet.
The servlet :
It must import a JSON librairy. I chose "JSONSimple" : simple and
enough for what I want to do.
Create a JSON array and put then name of the input field then true or false
after verification is made.
Create a writer in the response object and write the JSON array.
Nothing difficult ! ^_^
Example : "login" is the id of the input field
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
String login = new String(request.getParameter("login")); // we catch the value
JSONArray jsres = new JSONArray(); // new JSON array
jsres.add("login"); // 1st field : the field name = "login"
if(<login in the database ?>) jsres.add(new Boolean(false)); // In database ? => false in the JSON array
else jsres.add(new Boolean(true)); // Not in database > true in the JSON array !!
response.setContentType("application/json"); // The answer is in JSON content type
response.setCharacterEncoding("UTF-8"); // Put the right encoding
PrintWriter writer = response.getWriter(); // new answer writer
try {
writer.println(jsres); // WRITE !! ^_^
log.info("Retour JSON : " + jsres);
} catch(Exception e){
log.error("Erreur lors du transfert JSON : " + e.getMessage());
} finally {
writer.close(); // Don't forget to close the writer
}
}
It works fine...
If you have suggestions, I'll take with pleasure !
Now, I'll try to prevent the form submit because if the last condition is this condition, the submit appends ; I don't know why...