What is final modification in java?

The purpose of the final modifier (final): restricts the class from being inherited. Declare immutable constant variables. Prevent methods from being overridden by subclasses.

The role of final modifier in Java

The final modifier in Java is mainly used to restrict objects and members Modifications. It can be applied to the following:

Classes

• Declaring a class final prevents it from being inherited.

Variable

• Declaring a variable as final makes it a constant and its value cannot be changed.
• final variables must be initialized when declared.

Method

• Declaring a method as final prevents it from being overridden by subclasses.

Advantages of the final modifier

• Enforced immutability: Constant variables and immutable objects ensure data integrity.
• Improve performance: The compiler can inline final methods, thereby increasing execution speed.
• Prevent errors: Prevent accidental overwriting or inheritance, reducing the risk of errors.
• Improve security: Final methods cannot be overridden to avoid security vulnerabilities, such as rewriting security-related code.

When to use the final modifier

It is recommended to use the final modifier in the following situations:

• Make sure Objects or variables are immutable: Such as constants or immutable collections.
• Prevent inheritance: Such as sealed classes in design patterns.
• Prevent overwriting: Such as methods for security-critical tasks.
• Improve performance: Such as frequently called methods.

Note:

• Once declared as final, it cannot be modified.
• final variables cannot be reassigned.
• Final methods cannot be overridden by subclasses.

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