Can I Instantiate an Abstract Class?

[Mahendran Aiyappan]

Hi guys,

I am new to Java. I want to know whether I can instantiate an Abstract class, directly or indirectly. Please provide me your useful comments.


Thanks & Regards,
Mahendran A.

[Jesper de Jong]

Mahendran A, please check your private messages. You can see them by clicking My Private Messages.

To answer your question: No, you cannot instantiate an abstract class. An abstract class is a class that is not yet "finished" - it contains methods without an implementation. A non-abstract subclass is supposed to implement those methods.

See: The Java Tutorial - Abstract Methods and Classes.

[sudhir nim]

No abstract class can not be instantiated directly, but you can declare variables of abstract class type
[ November 16, 2007: Message edited by: sudhir nim ]

[Rob Spoor]

You can also create anonymous subclasses that implement all abstract methods:

AbstractAction action = new AbstractAction("Hello")
{
    public void actionPerformed(ActionEvent e)
    {
        // this is the only abstract method in AbstractAction
    }
}; // please note the semi-colon - this is still a statement that ends.

These anonymous subclasses only support the constructors of the abstract class though, you can't create your own ones. If you need that kind of behaviour you need to create actual subclasses.