- Can constructor be overloaded?
- What is super and this keyword?
- Can we override final method?
- Can we override private method?
- What would be the Behaviour If this () and super () used in a method?
- Why we Cannot override static method?
- Can we use this () and super () in a method?
- What is the difference between super and super () in Java?
- Can we override main method?
- How are this () and super () used with constructors?
- Why does this () and super () have to be the first statement in a constructor?
- Why super is used in constructor?
- Can you make constructor final?
- What is difference between i ++ and ++ i in Java?
- What is the difference between this () and super ()?
- What does super () do?
- Why is base constructor called first?
- Why we Cannot use this and super in static method?
Can constructor be overloaded?
Explanation: The constructor must be having the same name as that of a class.
Since the constructors can’t be defined in derived class, it can’t be overloaded too, in derived class.
Does constructor overloading include different return types for constructors to be overloaded?.
What is super and this keyword?
super() – refers immediate parent class instance. this() – refers current class instance. … this() acts as current class constructor and can be used in parametrized constructors. Override. When invoking a superclass version of an overridden method the super keyword is used.
Can we override final method?
A final method in a superclass cannot be overridden in a subclass—this guarantees that the final method implementation will be used by all direct and indirect subclasses in the hierarchy. Methods that are declared static are also implicitly final . …
Can we override private method?
No, a private method cannot be overridden since it is not visible from any other class. You have declared a new method for your subclass that has no relation to the superclass method. One way to look at it is to ask yourself whether it would be legal to write super. func() in the Derived class.
What would be the Behaviour If this () and super () used in a method?
What would be the behaviour if this() and super() used in a method? Explanation: this() and super() cannot be used in a method. This throws compile time error. … Explanation: Class class provides list of methods for use like getInstance().
Why we Cannot override static method?
Static methods cannot be overridden because they are not dispatched on the object instance at runtime. The compiler decides which method gets called. Static methods can be overloaded (meaning that you can have the same method name for several methods as long as they have different parameter types).
Can we use this () and super () in a method?
this() and super(), both are the constructors that’s why must be the first statement. But we can use both in a program. this(): It is used to call, same class Default or Parametrized Constructor. super(): It is used to call, immediate super/parent class Default or Parametrized Constructor.
What is the difference between super and super () in Java?
Difference between super and super() The super keyword in Java is a reference variable that is used to refer parent class objects. The super() in Java is a reference variable that is used to refer parent class constructors. super can be used to call parent class’ variables and methods.
Can we override main method?
The short answer to, can we overload the main method in Java is Yes, you can overloading, nothing stops from overloading, but JVM will always call the original main method, it will never call your overloaded main method. … the answer is No because main is a static method and static method cannot be overridden in Java.
How are this () and super () used with constructors?
How are this() and super() used with constructors? Constructors use this to refer to another constructor in the same class with a different parameter list. Constructors use super to invoke the superclass’s constructor. If a constructor uses super, it must use it in the first line; otherwise, the compiler will complain.
Why does this () and super () have to be the first statement in a constructor?
The Eclipse compiler says “Constructor call must be the first statement in a constructor”. So, it is not stopping you from executing logic before the call to super. It is just stopping you from executing logic that you can’t fit into a single expression.
Why super is used in constructor?
Can you make constructor final?
No, a constructor can’t be made final. A final method cannot be overridden by any subclasses. As mentioned previously, the final modifier prevents a method from being modified in a subclass. … In other words, constructors cannot be inherited in Java therefore, there is no need to write final before constructors.
What is difference between i ++ and ++ i in Java?
7 Answers. They both increment the number. ++i is equivalent to i = i + 1 . … Both increment the number, but ++i increments the number before the current expression is evaluted, whereas i++ increments the number after the expression is evaluated.
What is the difference between this () and super ()?
Difference between super() and this() in java Program this keyword mainly represents the current instance of a class. On other hand super keyword represents the current instance of a parent class. this keyword used to call default constructor of the same class.
What does super () do?
The super keyword refers to superclass (parent) objects. It is used to call superclass methods, and to access the superclass constructor. The most common use of the super keyword is to eliminate the confusion between superclasses and subclasses that have methods with the same name.
Why is base constructor called first?
The data members and member functions of base class comes automatically in derived class based on the access specifier but the definition of these members exists in base class only. … This is why the constructor of base class is called first to initialize all the inherited members.
Why we Cannot use this and super in static method?
A static method or, block belongs to the class and these will be loaded into the memory along with the class. … This implies that to use “super” the method should be invoked by an object, which static methods are not. Therefore, you cannot use “super” keyword from a static method.