Nullpointer Exception on null check statement

Question

How is the null check statement below throwing a Nullpointer Exception? Is the request perhaps null? I'm confused Somebody help.

if(!getTGTid(request).equalsIgnoreCase(null) || 
!getTGTid(request).equalsIgnoreCase("")) {

Method

private String getTGTid(HttpServletRequest request) {
return request.getParameter("tgtId"); 
}

Answer 1

If getTGTid(request) is null, getTGTid(request).equalsIgnoreCase(null) will throw NullPointerException.

Use

if (getTGTid(request) != null && !getTGTid(request).equalsIgnoreCase(""))