Why is this not throwing a NullPointerException?

Question

Nead clarification for following code:

StringBuilder sample = new StringBuilder();
StringBuilder referToSample = sample;
referToSample.append(\"B\");
System.         


        

Answer 1

Whenever a new keyword is used it Creates a Object at the Heap

1)StringBuilder sample = new StringBuilder();

2)StringBuilder referToSample = sample;

In 2) the Reference of referSample is created on same object sample

thus referToSample = null; is Nulling Only the referSample Reference giving no effect to sample that's why you are not getting NULL Pointer Exception Thanks to Java's Garbage Collection