Describe inner classes in java, JAVA Programming

Assignment Help:

Describe Inner Classes in java?

An inner class is a class whose body is described inside another class, referred to as the top-level class. For instance:
public class Queue {

Element back = null;

public void add(Object o) {

Element e = new Element();
e.data = o;
e.next = back;
back = e;

}

public Object remove() {

if (back == null) return null;
Element e = back;
while (e.next != null) e = e.next;
Object o = e.data;
Element f = back;
while (f.next != e) f = f.next;
f.next = null;
return o;

}

public boolean isEmpty() {
return back == null;
}

// Here's the inner class
class Element {

Object data = null;
Element next = null;
}

}
Inner classes may also holds methods. They may not contain static members.

Inner classes within a class scope can be public, private, protected, final, abstract.
Inner classes can also be used inside methods, loops, and other blocks of code surrounded by braces ({}). Such a class is not a member, and thus cannot be declared public, private, protected, or static.

The inner class has access to all the methods and fields of the top-level class, even the private ones.
The inner class's short name might not be used outside its scope. If you absolutely must use it, you can use the fully qualified name instead. (For instance, Queue$Element) Therefore, if you require doing this you should almost certainly have made it a top-level class instead or at least an inner class inside a broader scope.

Inner classes are most useful for the adapter classes needed through 1.1 AWT and JavaBeans event handling protocols. They permit you to implement callbacks. In most other languages this would bo done along with function pointers.


Related Discussions:- Describe inner classes in java

Image caching with html, In the airplane program, you may have noticed that...

In the airplane program, you may have noticed that the loading of each image appears to be jerky, erratic, or slow, and that the URL for each image flickers in the status bar each

JAVA Fundamentals, 15. Energy Drink Consumption A soft drink company recent...

15. Energy Drink Consumption A soft drink company recently surveyed 12,467 of its customers and found that approximately 14 percent of those surveyed purchase one or more energy dr

Jsf framework compare with the struts framework, Struts framework ...

Struts framework                            J a v a Server Faces More matured since Struts has been started for a few years. It has got var

Define object-to-relational (o/r) mapping, Object-to-Relational (O/R) mappi...

Object-to-Relational (O/R) mapping : There are various ways to persist data and the persistence layer is one of the most important layers in any application development. O/R ma

Logic circuit, Design a logic circuit to convert Gray code to Binary code a...

Design a logic circuit to convert Gray code to Binary code and draw the logic circuit.

Illustrate inheritance and composition?, The ' is a ' relationship is use...

The ' is a ' relationship is used with inheritance and ' has a ' relationship is used with composition . Both composition and inheritance allow you to perform sub-objects in

Describe even higer dimensions in java, Describe even higer dimensions in j...

Describe even higer dimensions in java? You don't have to stop along with two dimensional arrays. Java allows arrays of three, four or more dimensions. Therefore chances are pr

Need java programmer for an assignment, Need java programmer for an assignm...

Need java programmer for an assignment "Prepare a program that will accept a sequence of file names as command-line arguments. These files will consist of ASCII text representin

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd