java - What is the reasoning behind the Interface Segregation Principle?

Question

The Interface Segregation Principle (ISP) says that many client specific interfaces are better than one general purpose interface. Why is this important?

Answer 1

ISP states that:

Clients should not be forced to depend on methods that they do not use.

ISP relates to important characteristics - cohesion and coupling.
Ideally your components must be highly tailored. It improves code robustness and maintainability.

Enforcing ISP gives you following bonuses:

• High cohesion - better understandability, robustness
• Low coupling - better maintainability, high resistance to changes

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