query: Abstract & Inheritance classes NullPointer
positive_passages.docid: 49
positive_passages.text: What is a NullPointerException, and how do I fix it?
negative_passages.docid: 8808
negative_passages.text: Strange Java null behavior in Method Overloading
negative_passages.docid: 80018
negative_passages.text: Accessing class members on a NULL pointer
negative_passages.docid: 120220
negative_passages.text: Inheritance of Object Class in Java
negative_passages.docid: 125
negative_passages.text: Inheriting constructors
negative_passages.docid: 27908
negative_passages.text: Can we instantiate an abstract class?
negative_passages.docid: 114765
negative_passages.text: Why does casting an ArrayList 's generic to a superclass not work?
negative_passages.docid: 50570
negative_passages.text: When to use an interface instead of an abstract class and vice versa?
negative_passages.docid: 127599
negative_passages.text: Odd situation for "cannot reference this before supertype constructor has been called"
negative_passages.docid: 64332
negative_passages.text: avoiding null reference exceptions
negative_passages.docid: 155674
negative_passages.text: Multiple inheritance design issue in Java
negative_passages.docid: 39482
negative_passages.text: Abstract, Interface, Classes OH MY - Question on Approach
negative_passages.docid: 35590
negative_passages.text: How to fix NullPointerException in Java?
negative_passages.docid: 101146
negative_passages.text: Why can't I write Nullable>?
negative_passages.docid: 40822
negative_passages.text: Optional parameters and inheritance
negative_passages.docid: 130481
negative_passages.text: calling init for multiple parent classes with super?
negative_passages.docid: 36443
negative_passages.text: Specifying the return type of an abstract method from a Base Class according to a Sub Class