HTML5 FormData returns null in Java Servlet request.getParameter()

My view is HTML 5. I'm using FormData to make a AJAX 2 POST to a Servlet. Inside the servlet i'm trying to read request parameters. I can't see any parameters. However, Google Chrome Dev console shows the request payload. How can I get the same in Servlet code? Any help will be appreciated. Here's the code.

JS code

var xhr = new XMLHttpRequest();var formData = new FormData();formData.append('firstName', 'ABC');formData.append('lastName', 'XYZ');xhr.open("POST", targetLocation, true);xhr.send(formData);

Servlet code (both parameters return null)

out.println("Hello! "+ request.getParameter("firstName")+""+ request.getParameter("lastName")+", thanks for sending your feedback." );

Google Chrome Console

Content-Disposition: form-data; name="firstName"XYZContent-Disposition: form-data; name="lastName"ABC