What is the use of constructors in abstract classes?

Question

Since we cannot create an instance of an abstract class, then what is the need for constructors in the abstract class?

Answer 1

Abstract classes are designed to be extended, each constructor from a child must call the constructor from the base class , so you need constructors in the abstract class.

An abstract class is a skeleton and therefore it makes no sense to instantiate it directly, since it is still incomplete (children will provide the rest).

Answer 2

Example:

public abstract class BaseClass
{
    private String member;

    public BaseClass(String member)
    {
        this.member = member;
    }

    ... abstract methods...
}

public class ImplementingClass extends BaseClass
{
    public ImplementingClass(String member)
    {
        /* Implementing class must call a constructor from the abstract class */
        super(member);
    }

    ... method implementations...
}

Answer 3

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Answer 4

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