Question

How to insert JavaScript variable in JSP String variable.

<script>
    <%!
        String host_name = "tst" + location.host;
    %>
</script>

<%=host_name%> <!-- getting error -->

Thanks for help.

Answer 1

Javascript is executed in the browser, and JSP on the server. So you can’t directly get a value from javascript into JSP (java) : when the javascript is executed, JSP has finished its execution and sent the result.

Depending on your need, you may want to send a value using ajax from the browser to the server but it’s impossible to define the applicable strategy without knowing why you tried this.

If what you want is just have your hostname in java/jsp, I’d suggest you to do something along the lines of

<%
InetAddress addr = InetAddress.getLocalHost();
String hostname = addr.getHostName();
%>