Calling a Web Service in a JSP

Question

I am new to calling a REST service in a JSP. I have a form which goes through a struts2 action. I have a javascript function which performs a basic email validation. So instead of performing this validation using JavaScript I need to call a service which does email validation.

Do I need to call the validation service directly in JSP page if not then how can I achieve this.

<form name="resendEsignatureFormId" id="resendEsignatureFormId" action="<integration:urlAction actionName='/integration/resendEsignatureIntegration'></integration:urlAction>" 
    method="POST">
</form>

JavaScript function

function validate() {   
    // Need to call validation service here
    document.getElementById('resendEsignatureFormId').submit();
}

<table width=100%>
    <tr><td class="esignNavigation">            
       <a href="#x" onclick ="validate()"><span>Confirm</span></a>
       <a href="#x" onclick="hideSigners()"><span>Cancel</span></a></td>
    </tr>
</table>

Thanks in advance...

Answer 1

JSP is a java server-side technology to generate HTML on the server. A javascript call to a REST api is a browser -> server operation. So you don't call a REST service in a JSP, you call a REST service from javascript. That javascript can be invoked by an HTML event (onclick, etc.), and that HTML event may be described in a JSP - regardless of wether or not that event is dynamically generated by the JSP or just hard-coded.

You don't explicitly state that you have a server-side endpoint exposed to perform the email validation - you would need that as well.