What is the base 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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Can we use constructor in subclass?

The constructors of the subclass can initialize only the instance variables of the subclass . Thus, when a subclass object is instantiated the subclass object must also automatically execute one of the constructors of the superclass. To call a superclass constructor the super keyword is used.

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