What is Null pointer expections in Java

Question

#1 Question

Answer 1

https://stackoverflow.com/questions/218384/what-is-a-nullpointerexception-and-how-do-i-fix-it

Answer 2

if variable for some object is null
it means is empty
you can't call any method of object in variable, because there is not any object

Object o = null;
o.hashCode(); //NullPointerException

Answer 3

Adithya Keshav T
Exception definition is it is a runtime error
It is basic definition
Exception is a kind of error that can be handled but not rectified

Answer 4

NullPointerException is a runtime exception and it is thrown when we try to use an object reference which has a null value.
Ex:
https://code.sololearn.com/cWW2MY3wT22u/?ref=app

Answer 5

NullPointerException is a type of runtime error
The object that we are either created or in usage is not having memory

Ex : Student - class
It is having method wish();

I am doing this

Student s;
s.wish();

The above 2 statements will raise java.lang.NullPointerException
Since the value of s is null by default

Answer 6

sree harsha
NullPointer is an runtime exception.
Runtime errors are different from runtime exceptions.