What is the meaning of Possible null pointer dereference in findbug?

Question

I am using Sonar and I have got this kind of violation from it for a peace of my code:

 Correctness - Possible null pointer dereference  

Has a

Answer 1

I got this issue with the following piece of code:-

BufferedReader br = null;
    String queryTemplate = null;
    try {
        br = new BufferedReader(new FileReader(queryFile));
        queryTemplate = br.readLine();
    } catch (FileNotFoundException e) {
      //  throw exception
    } catch (IOException e) {
       // throw exception
    } finally {
        br.close();
    }

Here, the br BufferedReader can be null in br.close(). However it can only be null if new BufferedReader() fails, in which case we are throwing the relevant exceptions.

This is thus a false warning. Findbugs docs mention the same:-

   This may lead to a NullPointerException when the code is executed.  
   Note that because FindBugs currently does not prune infeasible 
   exception paths, this may be a false warning.