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What can be used instead of Instanceof in java?
isInstance() method is a method of class Class in java while instanceof is a operator. Now if we want to check the class of the object at run time, then we must use isInstance() method.
Can we do method overriding without inheritance?
If a method cannot be inherited, then it cannot be overridden. A subclass within the same package as the instance’s superclass can override any superclass method that is not declared private or final. A subclass in a different package can only override the non-final methods declared public or protected.
How does Instanceof work in java?
The java “instanceof” operator is used to test whether the object is an instance of the specified type (class or subclass or interface). It is also known as type comparison operator because it compares the instance with type. If we apply this operator with any variable that has null value, it returns false.
What does overriding mean in Java object oriented programming?
Overriding in Java In any object-oriented programming language, Overriding is a feature that allows a subclass or child class to provide a specific implementation of a method that is already provided by one of its super-classes or parent classes.
Do you need the same return type for overriding method in Java?
The overriding method must have same return type (or subtype) : From Java 5.0 onwards it is possible to have different return type for a overriding method in child class, but child’s return type should be sub-type of parent’s return type.
When to use overriding and access modifiers in Java?
Overriding and Access-Modifiers : The access modifier for an overriding method can allow more, but not less, access than the overridden method. For example, a protected instance method in the super-class can be made public, but not private, in the subclass. Doing so, will generate compile-time error.
Can a method override a synchronized method in Java?
Overriding and synchronized/strictfp method : The presence of synchronized/strictfp modifier with method have no effect on the rules of overriding, i.e. it’s possible that a synchronized/strictfp method can override a non synchronized/strictfp one and vice-versa. In C++, we need virtual keyword to achieve overriding or Run Time Polymorphism.