I can not use the method .equals(..), it throws NullPointerException

Question

 req.getParameter("doit").equal("good");

Is it impossible to write this line in the method? Without it, the program runs correctly. However whenever I write that line, it shows the error messages..

java.lang.NullPointerException at adhoc.FinePrint.doFilter(FinePrint.java:50)

Is there any way that I can check whether "doit" parameter is equal to "good"??

It says "The server encountered an internal error that prevented it from fulfilling this request. " — BBbbBB, Oct 28 '15 at 06:27
and "java.lang.NullPointerException at adhoc.FinePrint.doFilter(FinePrint.java:50)" — BBbbBB, Oct 28 '15 at 06:28
No you are seeing this error from the client side you have to check the error log on your server. — dsharew, Oct 28 '15 at 06:28
so that is the real problem `req.getParameter("doit")` is returning null. — dsharew, Oct 28 '15 at 06:29
But I checked that req.getParameter("doit") returns correct value. — BBbbBB, Oct 28 '15 at 06:30
Do you know the function is kind of recursive? make sure it has value on all the chain objects. — dsharew, Oct 28 '15 at 06:32
@BBbbBB Check my answer. Instead of use equal use equals method — Shiladittya Chakraborty, Oct 28 '15 at 06:41

score 2 · Accepted Answer · answered Oct 28 '15 at 06:45

2

I'd recommend to turn your equals around to

"good".equals(req.getParameter("doit"));

This prevents the NullPointerException when the request parameter "doit" is not set.

answered Oct 28 '15 at 06:45

Nitek

2,395
2
22
39

I can not use the method .equals(..), it throws NullPointerException

1 Answers1