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What are Java OOP pillars in detail?

Updated May 6, 2026

Short answer

OOP pillars are encapsulation, inheritance, polymorphism, abstraction.

Deep explanation

They structure software into modular, reusable components. Encapsulation hides data, inheritance reuses code, polymorphism enables flexibility, abstraction hides implementation.

Real-world example

Used in designing enterprise systems like banking software.

Common mistakes

  • Overusing inheritance instead of composition.

Follow-up questions

  • What is composition?
  • Why use abstraction?

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