What is object why it is used?

An object is an abstract data type with the addition of polymorphism and inheritance . Rather than structure programs as code and data, an object-oriented system integrates the two using the concept of an “object”. An object has state (data) and behavior (code). Objects can correspond to things found in the real world.

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When should you use objects Java?

Generally Object should only be used when dealing with a collection of elements of disparate or unknown type . This then usually is followed by instanceof and cast statements. Many APIs return Object when then can provide disparate types and some of this is a holdover from Java 4 and older prior to generics.

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