将值从jsp发送到Java或将javascript发送到Java

Question

I have a list of names in a table. When I click the name, it displays people under that particular name. Ex:

aaa       bbb
          ccc 

Now I want to do moveover on aaa which l show 2 (number of ppl under aaa) in a tooltip.

<a id="tool" title="toolTip" onmouseover="toolTip(localArrGroupNames[<%=in.intValue() %>])">

function toolTip(name){
  alert(name);
  //can I send this name to a java class ???

}

I get the name aaa in the localArrGroupNames[0].But I am unable to get the name in a java class where i count the number of people below the aaa. How to send this value to java class? Please help me.

Answer 1

function toolTip(name){
   alert(name);
   //can I send this name to a java class ???

    new Ajax.Request('jspFile.jsp', {
        parameters: {
            name: name
        },
        method: 'get',
        onComplete: function(transport) {
            var resp = transport.responseText.strip();
            $('tool').update(resp);
        }
    });
}

Answer 2

A jsp is server side, the rendered HTML is client side so the javascript is running in a webbrowser on the client.

To send any data from that client to your java class that is on the server you need to put in some form of request.

This can be simple by using a submit on your html form

So you could have your tooltip javascript method store the chosen name in a hidden input field and then via submit pass it to the java class( usuually a servlet or some jsp )

Or more complex with the AJAX ( or similar ) frameworks that allow your javascript to pass the name to your server without having the entire page to be submitted

Answer 3

you need to submit a request to the server you can do this using ajax to perform asynchronously, or you could submit using a form in the jsp page.

You will of course need to supply the correct url (either form action, or ajax connection url), and have the appropriate servlet running on server.

If doing ajax, most people use jquery and/or DWR

Answer 4

Remember that Javascript runs on the client side only, while Java is server side only. Java can set a Javascript variable since Java is processed by the server first and then javascript, csss, and html is sent back to the browser for processing.

To send Javascript variable to the server you must post your data from the client to the server. One way to do that is to submit a form another is to create an Ajax request (XML over HTTP) there are lots of JS libraries out there that can help with doing Ajax.