Final in Java vs. Finalize in Java — What's the Difference?

In Java, final is a keyword that, when applied to variables, means they cannot be reassigned; to methods, it means they cannot be overridden; and to classes, it implies they cannot be subclassed. On the other hand, finalize is a method in the Object class that the garbage collector calls just before object memory is reclaimed, allowing for clean-up activities.

The final keyword enhances stability and predictability of the code by preventing alteration of variables, overriding of methods, or subclassing of classes. Conversely, finalize provides a mechanism to perform finalization tasks on objects before they are garbage collected, such as releasing system resources or closing file handles, although its usage is generally discouraged in favor of try-with-resources and explicit resource management.

A variable declared as final must be initialized at the time of declaration or within the constructor of the class. This ensures immutability of the variable. The finalize method, however, is invoked implicitly by the Java runtime and cannot be predicted or relied upon due to the unpredictable nature of garbage collection, which makes it unsuitable for critical resource release.

In terms of best practices, the final keyword is widely used and recommended for ensuring constants, immutable objects, or defining unchangeable behavior of classes and methods. In contrast, the use of finalize is generally discouraged in modern Java programming due to its unpredictability and potential to cause issues, including delays in garbage collection and unpredictable behavior.

Overall, final and finalize serve different purposes: final is a language construct for defining unchangeable characteristics, whereas finalize is a legacy method for cleanup before an object is garbage collected. The former contributes to the clarity and robustness of the code, while the latter, due to its unpredictability, is less commonly used in contemporary Java development.