An object that implements the Enumeration interface generates a series of elements, one at a time. It has two methods, namely hasMoreElements() and nextElement(). HasMoreElemnts() tests if this enumeration has more elements and nextElement method returns successive elements of the series.
2
what is an Object?
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Objectis an instance of a class and it is a software unit that combines a structured set of data with a set of operations for inspecting and manipulating that data. When an object is created using new operator, memory is allocated to it.
3
what is Interface?
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Interface is similar to a class which may contain method’s signature only but not bodies and it is a formal set of method and constant declarations that must be defined by the class that implements it. Interfaces are useful for:
4
what is Methods ?
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Methods are functions that operate on instances of classes in which they are defined. Objects can communicate with each other using methods and can call methods in other classes.
5
what is abstract class?
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Abstract class is a class designed with implementation gaps for subclasses to fill in and is deliberately incomplete.
6
what is super class ?
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Super class is a class that is inherited whereas sub class is a class that does the inheriting.
7
what is package?
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Package is a collection of classes and interfaces that provides a high-level layer of access protection and name space management.
8
What is Primitive Data Type?
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Primitive data types are 8 types and they are: byte, short, int, long, float, double, boolean, char.
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what are Wrapper classes?
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The classes that allow primitive types to be accessed as objects.
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What is Class?
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Class is a template for multiple objects with similar features and it is a blue print for objects. It defines a type of object according to the data the object can hold and the operations the object can perform.
