An abstract class is a class that is declared abstract. it may or may not include abstract methods. Abstract classes cannot be instantiated, but they can be subclassed.

An abstract method is a method that is declared without an implementation (without braces, and followed by a semicolon), like this:

abstract void moveTo(double deltaX, double deltaY);

If a class includes abstract methods, the class itself must be declared abstract, as in:

public abstract class GraphicObject {
// declare fields
// declare non-abstract methods
abstract void draw();
}

When an abstract class is subclassed, the subclass usually provides implementations for all of the abstract methods in its parent class. However, if it does not, the subclass must also be declared abstract.

Answered by Rocky , an ibibo Master, at 7:18 PM on July 19, 2008

An abstract class is a class that is declared abstract. it may or may not include abstract methods. Abstract classes cannot be instantiated, but they can be subclassed.

An abstract method is a method that is declared without an implementation (without braces, and followed by a semicolon), like this:

abstract void moveTo(double deltaX, double deltaY);

If a class includes abstract methods, the class itself must be declared abstract, as in:

public abstract class GraphicObject {
// declare fields
// declare non-abstract methods
abstract void draw();
}

When an abstract class is subclassed, the subclass usually provides implementations for all of the abstract methods in its parent class. However, if it does not, the subclass must also be declared abstract.

Answered by Ni .. , an ibibo Master, at 4:48 PM on July 15, 2008

An abstract class is a class that is declared abstract. it may or may not include abstract methods. Abstract classes cannot be instantiated, but they can be subclassed.

An abstract method is a method that is declared without an implementation (without braces, and followed by a semicolon), like this:

abstract void moveTo(double deltaX, double deltaY);

If a class includes abstract methods, the class itself must be declared abstract, as in:

public abstract class GraphicObject {
// declare fields
// declare non-abstract methods
abstract void draw();
}

When an abstract class is subclassed, the subclass usually provides implementations for all of the abstract methods in its parent class. However, if it does not, the subclass must also be declared abstract.

Answered by .... ..... , an ibibo Master, at 6:24 AM on July 12, 2008

An abstract class is a class that is declared abstract. it may or may not include abstract methods. Abstract classes cannot be instantiated, but they can be subclassed.

An abstract method is a method that is declared without an implementation (without braces, and followed by a semicolon), like this:

abstract void moveTo(double deltaX, double deltaY);

If a class includes abstract methods, the class itself must be declared abstract, as in:

public abstract class GraphicObject {
// declare fields
// declare non-abstract methods
abstract void draw();
}

When an abstract class is subclassed, the subclass usually provides implementations for all of the abstract methods in its parent class. However, if it does not, the subclass must also be declared abstract.

Answered by Yash , an ibibo Master, at 12:26 AM on July 10, 2008

An abstract class is a class that is declared abstract. it may or may not include abstract methods. Abstract classes cannot be instantiated, but they can be subclassed.

An abstract method is a method that is declared without an implementation (without braces, and followed by a semicolon), like this:

abstract void moveTo(double deltaX, double deltaY);

If a class includes abstract methods, the class itself must be declared abstract, as in:

public abstract class GraphicObject {
// declare fields
// declare non-abstract methods
abstract void draw();
}

When an abstract class is subclassed, the subclass usually provides implementations for all of the abstract methods in its parent class. However, if it does not, the subclass must also be declared abstract.

For more visit :

http://java.sun.com/docs/ books/tutorial/java/IandI/abst ract.html

Answered by Raksha , an ibibo Master, at 9:44 AM on July 09, 2008

well, well, An abstract class is a class that is declared abstract. it may or may not include abstract methods. Abstract classes cannot be instantiated, but they can be subclassed.

An abstract method is a method that is declared without an implementation (without braces, and followed by a semicolon), like this:

abstract void moveTo(double deltaX, double deltaY);

If a class includes abstract methods, the class itself must be declared abstract, as in:

public abstract class GraphicObject {
// declare fields
// declare non-abstract methods
abstract void draw();
}

When an abstract class is subclassed, the subclass usually provides implementations for all of the abstract methods in its parent class. However, if it does not, the subclass must also be declared abstract.

For more visit :

http://java.sun.com/docs/ books/tutorial/java/IandI/abst ract.html

Answered by Romi , an ibibo Master, at 4:06 PM on July 03, 2008

An abstract class is a class that is declared abstract. it may or may not include abstract methods. Abstract classes cannot be instantiated, but they can be subclassed.

An abstract method is a method that is declared without an implementation (without braces, and followed by a semicolon), like this:

abstract void moveTo(double deltaX, double deltaY);

If a class includes abstract methods, the class itself must be declared abstract, as in:

public abstract class GraphicObject {
// declare fields
// declare non-abstract methods
abstract void draw();
}

When an abstract class is subclassed, the subclass usually provides implementations for all of the abstract methods in its parent class. However, if it does not, the subclass must also be declared abstract.

For more visit :

http://java.sun.com/docs/ books/tutorial/java/IandI/abst ract.html

Answered by Sharad Singh , an ibibo Master, at 6:15 PM on June 25, 2008

The abstract class can be defined as-

Abstract class must be extended/subclassed (to be useful). It serves as a template. A class that is abstract may not be instantiated (ie, you may not call its constructor), abstract class may contain static data. Any class with an abstract method is automatically abstract itself, and must be declared as such.
A class may be declared abstract even if it has no abstract methods. This prevents it from being instantiated.

Answered by Madhurima , an ibibo Master, at 1:42 PM on June 25, 2008

The abstract class can be defined as-

Abstract class must be extended/subclassed (to be useful). It serves as a template. A class that is abstract may not be instantiated (ie, you may not call its constructor), abstract class may contain static data. Any class with an abstract method is automatically abstract itself, and must be declared as such.
A class may be declared abstract even if it has no abstract methods. This prevents it from being instantiated.

Answered by Nagendra , an ibibo Master, at 7:59 AM on June 25, 2008

An abstract class is a type of class that cannot be instantiated, it merely exists to be extended and contains methods and varaibles common to all sub-classes.


An abstract class is a class that is declared abstract—it may or may not include abstract methods. Abstract classes cannot be instantiated, but they can be subclassed.

An abstract method is a method that is declared without an implementation (without braces, and followed by a semicolon), like this:

abstract void moveTo(double deltaX, double deltaY);

If a class includes abstract methods, the class itself must be declared abstract, as in:

public abstract class GraphicObject {
// declare fields
// declare non-abstract methods
abstract void draw();
}

When an abstract class is subclassed, the subclass usually provides implementations for all of the abstract methods in its parent class. However, if it does not, the subclass must also be declared abstract.
Note: All of the methods in an interface (see the Interfaces section) are implicitly abstract, so the abstract modifier is not used with interface methods (it could be—it's just not necessary).

Answered by Om Prakash , an ibibo Master, at 7:07 PM on June 24, 2008