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How to inherit the constructor from a super class to a sub class?
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To explicitly call the superclass constructor from the subclass constructor, we use super() . It's a special form of the super keyword. super() can be used only inside the subclass constructor and must be the first statement.
To call the constructor for each superclass within the subclass constructor, use the following syntax: obj@SuperClass1(args,...); ... obj@SuperclassN(args,...);
Constructors are not inherited. The superclass constructor can be called from the first line of a subclass constructor by using the keyword super and passing appropriate parameters to set the private instance variables of the superclass.
You can try to convert the super class variable to the sub class type by simply using the cast operator. But, first of all you need to create the super class reference using the sub class object and then, convert this (super) reference type to sub class type using the cast operator.
Constructors are not inherited, you must create a new, identically prototyped constructor in the subclass that maps to its matching constructor in the superclass.
Here is an example of how this works:
class Foo { Foo(String str) { } } class Bar extends Foo { Bar(String str) { // Here I am explicitly calling the superclass // constructor - since constructors are not inherited // you must chain them like this. super(str); } } Superclass constructor CAN'T be inherited in extended class. Although it can be invoked in extended class constructor's with super() as the first statement.
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