This rule raises an issue when a finalizer assign `null` to fields of the instance it is called on. == Why is this an issue? In the Java object lifecycle, the `finalize` method for an instance is called after the garbage collector has determined that the instance can be removed from the object heap. Therefore, it is unnecessary to implement a finalizer to set instance fields explicitly to `null` to tell the garbage collector that the instance no longer needs them. In the worst case, implementing `finalize` is even counterproductive because it might accidentally create new references from other (living) objects on the heap to the collectible instance, thus, reviving it. **Important note about finalizers:** There are no guarantees when the Java Runtime will call the `finalize` method or whether it will be called at all. Using finalizers is, therefore, a bad practice. They should never be used to free resources, such as closing streams, freeing locks, or freeing native system resources. Consider other freeing mechanisms instead, such as an explicit `close`, `unlock`, or `free` method in your class. == How to fix it Remove assignments from your finalizer that assign `null` to fields of the instance the finalizer is called on. When this leaves you with an empty finalizer body, remove the finalizer. === Code examples ==== Noncompliant code example [source,java,diff-id=1,diff-type=noncompliant] ---- public class Foo { private String name; @Override void finalize() { name = null; // Noncompliant, instance will be removed anyway } } ---- ==== Compliant solution [source,java,diff-id=1,diff-type=compliant] ---- public class Foo { // Compliant private String name; } ---- == Resources === Documentation * https://docs.oracle.com/javase/8/docs/api/java/lang/Object.html#finalize--[Java SE 8 API Specification - Object.finalize] === Articles & blog posts * https://howtodoinjava.com/java/basics/why-not-to-use-finalize-method-in-java[Java finalize() – Why We Should Not Use It? - Lokesh Gupta] * https://www.baeldung.com/java-finalize[A Guide to the finalize Method in Java - Baeldung] ifdef::env-github,rspecator-view[] ''' == Implementation Specification (visible only on this page) === Message Remove this nullification of "xxx". endif::env-github,rspecator-view[]