Can we assign parent object to child reference in Java?

The reference variable of the Parent class is capable to hold its object reference as well as its child object reference. In Java, methods are virtual by default (See this for details).

Can we assign parent object to child objects in Java?

The parent class can hold reference to both the parent and child objects. If a parent class variable holds reference of the child class, and the value is present in both the classes, in general, the reference belongs to the parent class variable. This is due to the run-time polymorphism characteristic in Java.

Can parent reference call child method in Java?

we can called the overridden methods of child class with parent class reference we can not call the direct child class methods from parent class reference. we can called the overridden methods of child class with parent class reference we can not call the direct child class methods from parent class reference.

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Can we cast parent to child in Java?

However, we can forcefully cast a parent to a child which is known as downcasting. After we define this type of casting explicitly, the compiler checks in the background if this type of casting is possible or not. If it’s not possible, the compiler throws a ClassCastException.

Can child class create parent object?

In Simple Terms, Objects of Parent class can hold objects of child class. The reverse could not be true.

Can parent reference hold child object?

The reference variable of the Parent class is capable to hold its object reference as well as its child object reference. In Java, methods are virtual by default (See this for details).

Can we assign the parent class object to the subclass as a reference?

No. It makes zero sense to allow that. The reason is because subclasses generally define additional behavior. If you could assign a superclass object to a subclass reference, you would run into problems at runtime when you try to access class members that don’t actually exist.

Can an object of a child type be assigned to a variable of the parent type?

Yes—an object can be assigned to a reference variable of the parent type.

How do you create a parent and child class in Java?

To create a sub class (child) from a Java super class (parent), the keyword extends is used. You then follow the “extends” keyword with the parent class you want to extend.

Which object is parent of all other object?

Explanation: The Object class is the parent class of all the classes in java by default. In other words, it is the topmost class of java. …

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Is downcasting possible in Java?

Upcasting is allowed in Java, however downcasting gives a compile error. The compile error can be removed by adding a cast but would anyway break at the runtime.

Why do we need Upcasting and downcasting in Java?

Why we need Upcasting and Downcasting? In Java, we rarely use Upcasting. We use it when we need to develop a code that deals with only the parent class. Downcasting is used when we need to develop a code that accesses behaviors of the child class.

Can you cast a parent to a child?

Parent to Child (Explicit casting – Can be successful)

Note: Because objects has polymorphic nature, it is possible for a variable of a parent class type to hold a child type. Conclusion : After reading above all, hope it will make sense now like how parent to child conversion is possible(Case 3).

How do you create an object of a child class in Java?

Along with other functions of constructor it also instantiate the properties/instances of its class.In java by default super() method is used as first line of constructor of every class,here the purpose of this method is to invoke constructor of its parent class so that the properties of its parent get well …

Is overriding possible in Java?

Instance methods can be overridden only if they are inherited by the subclass. A method declared final cannot be overridden. A method declared static cannot be overridden but can be re-declared. If a method cannot be inherited, then it cannot be overridden.

What is parent object in Java?

The Object class is the parent class of all the classes in java by default. In other words, it is the topmost class of java. The Object class is beneficial if you want to refer any object whose type you don’t know. Notice that parent class reference variable can refer the child class object, know as upcasting.

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