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Java Quick Syntax Reference
book

Java Quick Syntax Reference

by Mikael Olsson
January 2018
Intermediate to advanced content levelIntermediate to advanced
115 pages
1h 37m
English
Apress
Content preview from Java Quick Syntax Reference
© Mikael Olsson 2018
Mikael OlssonJava Quick Syntax Referencehttps://doi.org/10.1007/978-1-4842-3441-9_18

18. Abstract

Mikael Olsson1 
(1)
Hammarland, Länsi-Suomi, Finland
 

An abstract class provides a partial implementation that other classes can build upon. When a class is declared abstract, it means it can contain incomplete methods that must be implemented in subclasses, in addition to normal class members. These methods are left unimplemented and only specify their signatures, while their bodies are replaced by semicolons:

abstract class Shape
{
  public int x = 100, y = 100;
  public abstract int getArea();
}

Abstract class example

If a class called Rectangle inherits from the abstract class Shape, Rectangle is then forced to override the abstract ...

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Publisher Resources

ISBN: 9781484234419Purchase LinkPublisher Website