What will be the initial value of an object reference which is defined as an instance variable?

Java Interview Questions and Answers (part 3)

(Continued from previous question...)

556. What will be the initial value of an object reference which is defined as an instance variable?

The object references are all initialized to null in Java. However in order to do anything useful with these references, you must set them to a valid object, else you will get NullPointerExceptions everywhere you try to use such default initialized references.

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