Pass Javascript Value to Java in JSP

Question

I would like to pass a Javascript value to a Java function in JSP. How can I do that? The id comes from a combobox in JSP via Javascript. I will get the ID from ComboBox and send it to Java function as parameter to get the Java result.

function Display()
{
   var IdFromCB = (document.getElementById("MListSelect")).value;
   //CALL JAVA FUNCTION HERE BY USING IdFromCB as function parameter
   //'<% getSomething(-----IdFromCB-----);%>'

}

Thanks,Mark

Solution 1

You cannot make a server call directly. You need to make a server request.

javascript plays on client side and JSP plays on server side.

What you need is you have to make a server request. And send that string as a query parameter.

Two options to achieve this.

• HTML forms
• Ajax.

Do not confuse that JSP and java script existed on same document(or file). Yes but JSP part compiles on server side and JavaScript executes by browser.

Solution 2

Javascript statements are rendered by Browsers and executed as client program.

In your case if you want execute a java code based on selection of html component, you would need to use ajax call .

You can find quick example here

A Simple AJAX with JSP example

http://www.programming-free.com/2013/03/ajax-fetch-data-from-database-in-jsp.html