Abstract class vs interface

In Java, abstract is a non-access modifier in java applicable for classes, and methods but not variables.

Abstraction in java

It is used to achieve abstraction which is one of the pillars of Object Oriented Programming(OOP). Following are different contexts where abstract can be used in Java.

Characteristics of Java Abstract Keyword

In Java, the abstract keyword is used to define abstract classes and methods.

Here are some of its key characteristics:

• Abstract classes cannot be instantiated: An abstract class is a class that cannot be instantiated directly. Instead, it is meant to be extended by other classes, which can provide concrete implementations of its abstract methods.
• Abstract methods do not have a body: An abstract method is a method that does not have an implementation.

  It is declared using the abstract keyword and ends with a semicolon instead of a method body. Subclasses of an abstract class must provide a concrete implementation of all abstract methods defined in the parent class.

• Abstract classes can have both
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