Inheritance

Inheritance is a way to define a class by reusing the definition of another class.

Related concepts:  ClassMemberSubtyping

Closest Wikipedia entry:  Inheritance (object-oriented programming)

Misconceptions about Inheritance

16 documented Misconceptions

AbstractClassMustImplementAbstractMethod

An abstract class must implement all abstract methods defined in its superclass

AbstractClassNoImplementation

An abstract class cannot contain implemented methods

ConcreteClassMustOverride

A concrete class needs to implement all methods declared in its abstract superclasses

ConcreteClassOnlyImplementClassAbstract

A concrete class only needs to implement those abstract methods it inherits from abstract superclasses

ConcreteClassOnlyImplementDirectAbstract

A concrete class only needs to implement abstract methods declared in its direct supertypes

ConcreteClassOnlyImplementInterfaceAbstract

A concrete class only needs to implement those abstract methods it inherits from interfaces

ImplicitInterfaceImplementation

Java implicitly produces implementations of any methods a class inherits from the interfaces it implements

InterfaceExtendClass

An interface can extend a class

NoMethodInheritance

Subclasses inherit fields but not methods

PrivateAccessibleInSubclass

Private members of a superclass are accessible from a subclass

StaticDispatch

The method to be called is determined by the static type

SubtypeCompatibleWithSupertype

A variable of a subtype can reference an object of a supertype

SuperAlwaysHasParentheses

To call a method on a superclass, parentheses are needed after the keyword super

SuperNotFirstStatement

super() can be called anywhere in the constructor of a subclass

SuperclassObjectAllocated

When instantiating an object of a subclass, an object of a superclass is also allocated

SupertypeIncompatibleWithSubtype

A variable of a supertype cannot reference an object of a subtype