A class that is declared using “abstract” keyword is known as abstract class. It can have abstract methods(methods without body) as well as concrete methods (regular methods with body). A normal class(non-abstract class) cannot have abstract methods.
Read moreWhat are the 4 types of Java?
There are four platforms of the Java programming language: Java Platform, Standard Edition (Java SE) Java Platform, Enterprise Edition (Java EE) Java Platform, Micro Edition (Java ME)
Read moreWhat is standard classes in Java?
Java’s standard classes are analogous to off-the-shelf hardware components . Java includes a multitude of classes. These classes are organized into collections called packages. In order to speed compilation and class loading during execution, the compiler normally has access to a small subset of the standard classes.
Read moreWhere do you put inner classes?
I would declare inner-classes in the bottom of the file – usually you’re not interested in their implementations and just want to get to your main class’ methods, so they shouldn’t get in the way.
Read moreWhat is the difference between nested class and inner class in Java?
In Java programming, nested and inner classes often go hand in hand. A class that is defined within another class is called a nested class. An inner class, on the other hand, is a non-static type, a particular specimen of a nested class.
Read moreWhat is the difference between an inner class and a subclass in Java?
inner classes are in the same file, whereas subclasses can be in another file, maybe in another package . You cannot get an instance of an inner class without an instance of the class that contains it.
Read moreHow do you add an inner class in Java?
Creating an inner class is quite simple. You just need to write a class within a class . Unlike a class, an inner class can be private and once you declare an inner class private, it cannot be accessed from an object outside the class. Following is the program to create an inner class and access it.
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