'ThreadLocal.set()' with null as an argument

Reports java.lang.ThreadLocal.set() with null as an argument.

This call does not free the resources, and it may cause a memory leak.

It may happen because:

Firstly, ThreadLocal.set(null) finds a map associated with the current Thread. If there is no such a map, it will be created
It sets key and value: map.set(this, value), where this refers to instance of ThreadLocal

java.lang.ThreadLocal.remove() should be used to free the resources.

Example:

  ThreadLocal<Integer> threadLocal = new ThreadLocal<>();
  threadLocal.set(null);

After the quick-fix is applied:

threadLocal.remove();

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ThreadLocalSetWithNull

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New in 2023.2

Inspection Details
By default bundled with:	IntelliJ IDEA 2024.2, Qodana for JVM 2024.2,
Can be installed with plugin:	Java, 242.22892

Last modified: 11 September 2024