6. Advantages and Disadvantages of immutable class?

Question

Accepted Answer

Immutable classes have advantages like thread safety, security, and simplicity, but also have disadvantages like memory usage and performance overhead.

Advantages of immutable classes:
- Thread safety: Immutable objects can be safely shared among multiple threads without the need for synchronization.
- Security: Immutable objects cannot be modified, which can prevent unauthorized changes to sensitive data.
- Simplicity: Immutable objects are easier to reason about and debug since their state cannot change.
Disadvantages of immutable classes:
- Memory usage: Immutable objects can consume more memory, especially when frequent modifications are required.
- Performance overhead: Creating new instances of immutable objects can be slower than modifying mutable objects directly.

Accepted Answer

Advantages:

Thread-safety: Immutable classes are thread-safe and can be safely shared among multiple threads without any risk of race conditions or synchronization issues.
Security: Immutable classes cannot be modified once created, which makes them more secure than mutable classes. This is particularly useful when dealing with sensitive information such as passwords, cryptographic keys, and financial data.
Simplified code: Immutable classes can simplify code by reducing the need for defensive copying, synchronization, and other boilerplate code that is typically required when working with mutable objects.
Cache-friendly: Immutable classes are more cache-friendly than mutable classes, as they do not require any expensive memory allocation or garbage collection operations.
Reliable hash code: Immutable classes always produce the same hash code, which makes them more reliable as keys in hash-based collections such as HashMap.

Disadvantages:

Memory usage: Immutable classes can use more memory than mutable classes, as they require the creation of a new object every time their state is changed.
Performance overhead: Immutable classes can have a performance overhead due to the need for creating new objects and copying state.
Limited flexibility: Immutable classes are not suitable for situations where frequent modifications of object state are required.
Complexity: Immutable classes can be more complex to implement than mutable classes, particularly when dealing with complex object graphs.

6. Advantages and Disadvantages of immutable class?

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