What's difference between weak, strong and read only??

Question

Accepted Answer

Weak, strong and read only are types of references in programming languages.

Strong reference keeps the object in memory until the reference is set to null or goes out of scope.
Weak reference allows the object to be garbage collected if there are no strong references to it.
Read-only reference allows the object to be read but not modified.
Weak references are useful for caching and avoiding memory leaks.
Read-only references are useful for sharing data without allowing modification.

Accepted Answer

In programming languages, particularly in the context of references, memory management, and data mutability, the terms "weak reference," "strong reference," and "read-only reference" describe different ways in which references to objects are handled. These concepts are not exclusive to all programming languages, but they are commonly found in languages that support dynamic memory management and object-oriented programming.

Strong Reference: A strong reference is the most common type of reference. When you create a strong reference to an object, it means that the object will not be garbage-collected as long as there is at least one strong reference pointing to it. In other words, the reference keeps the object alive. Most references in programming languages are strong references by default. For example, in languages like Java, C#, and Python, when you assign an object to a variable, you're creating a strong reference.
Weak Reference: A weak reference is a reference that does not prevent the object it points to from being garbage-collected. In languages that support weak references, objects can be collected by the garbage collector even if there are only weak references to them. Weak references are useful in scenarios where you want to maintain a non-essential reference to an object, without preventing it from being reclaimed by memory management when it's no longer strongly referenced. This can be helpful for implementing caching, observer patterns, or avoiding memory leaks.
Read-Only Reference: A read-only reference is not directly related to memory management but instead relates to the ability to modify the object through the reference. A read-only reference typically implies that you can access the object's properties and methods, but you cannot modify its internal state. It's a way to enforce immutability or prevent accidental modification of an object. This concept is more about the permissions and access control of the reference, rather than its impact on memory management.

What's difference between weak, strong and read only??

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