java.lang.NullPointerException

java.lang.Object

 java.lang.Throwable

   java.lang.Exception

     java.lang.RuntimeException

       java.lang.NullPointerException

 

public class NullPointerException extends RuntimeException

Thrown when an application attempts to use null in a case where an object is required.

These include:

Calling the instance method of a null object.

Accessing or modifying the field of a null object.

Taking the length of null as if it were an array.

Accessing or modifying the slots of null as if it were an array.

Throwing null as if it were a Throwable value.

Applications should throw instances of this class to indicate other illegal uses of the null object. 

NullPointerExceptionobjects may be constructed by the virtual machine as if suppression weredisabled and/or the stack trace was not writable.