The Entry in the cache array of a ClassValueMap keeps a value in an outdated association alive when the ClassValue is garbage collected, which is technically a resource leak.

See this test:

    @Test
    void testWeakAgainstClassValue() {
        ClassValue<int[]> cv = new ClassValue<>() {
            @Override
            protected int[] computeValue(Class<?> type) {
                return new int[23];
            }
        };

        WeakReference<?> ref = new WeakReference<>(cv.get(int.class));
        cv = null; // Remove reference for interpreter
        if (!ForceGC.wait(() -> ref.refersTo(null))) {
            fail("Timeout");
        }
    }