Abstract Classes contain the work abstract in it. It is used when you know that you will need to use an object of its type but do not know the inner workings yet. Anonymous classes are those classes that are constructed on the fly. You need to know its inner workings.
an abstract class is nothing but class which contains both abstract and concrete methods for abstract class we r nt create object Syntax for pure abstract class is abstract class x { public void abstract y(); public void abstract z(); public void abc() { }
Any class which has one or more abstract methods is called an abstract class. But in the normal class we can't have any abstract methods. We cannot create an object for the abstract classes. When we inherit the abstract class we should implement the abstract method which we inherit.
An abstract class cannot have a constructor and hence you cannot invoke the constructor of the class - i.e., you can instantiate an abstract class and hence you cannot call the constructor of an abstract class.
False. In fact, it is possible to have no abstract methods in an abstract class.
A constructor of a class in invoked when a object of that class is created. As an abstract class can't have an object, so we can't create a constructor of the abstract class. But we can create a constructor of a concrete subclass of that abstract class and we have to pass the object of that concrete subclass to the abstract class.
an abstract class is nothing but class which contains both abstract and concrete methods for abstract class we r nt create object Syntax for pure abstract class is abstract class x { public void abstract y(); public void abstract z(); public void abc() { }
Any class which has one or more abstract methods is called an abstract class. But in the normal class we can't have any abstract methods. We cannot create an object for the abstract classes. When we inherit the abstract class we should implement the abstract method which we inherit.
The abstract noun forms of the verb to compare are comparison and the gerund, comparing.
class is defined in the class
An abstract class cannot have a constructor and hence you cannot invoke the constructor of the class - i.e., you can instantiate an abstract class and hence you cannot call the constructor of an abstract class.
False. In fact, it is possible to have no abstract methods in an abstract class.
The classes which have one or more abstract methods are abstract. To declare a class as abstract, use the abstract keyword in front of the class keyword, before the class declaration. Abstract classes cannot be instantiated. Similarly the new keyword cannot be used to create an object of the abstract class. Remember that the constructors and static variables cannot be declared as abstract. Any subclass of an abstract class must either implement all of the abstract methods in the superclass or be itself declared abstract.
A constructor of a class in invoked when a object of that class is created. As an abstract class can't have an object, so we can't create a constructor of the abstract class. But we can create a constructor of a concrete subclass of that abstract class and we have to pass the object of that concrete subclass to the abstract class.
An anonymous class is a local class without a name. An anonymous class is defined and instantiated in a single succinct expression using the new operator. While a local class definition is a statement in a block of Java code, an anonymous class definition is an expression, which means that it can be included as part of a larger expression, such as a method call. When a local class is used only once, consider using anonymous class syntax, which places the definition and use of the class in exactly the same place.New Syntax for Anonymous ClassesWe've already seen examples of the syntax for defining and instantiating an anonymous class. We can express that syntax more formally as: new class-name ( [ argument-list ] ) { class-body }or: new interface-name () { class-body }
An abstract class is a class that cannot be directly instantiated. The purpose of such a class is to put some logic in a base class and force derived classes to implement the remaining functionality. Since the full functionality is only available in the derived class, the base class is declared as abstract so that it cannot be instantiated directly.
The abstract nouns for the verb to compare are comparison and the gerund, comparing.
True - an instance of an abstract class cannot be created. False - derive (subclass) from a class, not the object (the instance).