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I was intrigued by the answer to a similar question. I believe it is incorrect. So I created some test code. My question is, does this code prove/disprove/inconclusive the hypothesis that it is useful to nullify member variables in teardown methods? I tested it with JUnit4.8.1. JUnit creates a new instance of the test class for each of the 4 tests. Each instance contains an Object obj. This obj is also inserted as the key of a static WeakHashMap. If and when JUnit releases its references to a test instance, the associated obj value will become weakly referenced and thus eligible for gc. The test tries to force a gc. The size of the WeakHashMap will tell me whether or not the objs are gc'ed. Some tests nullified the obj variable and others did not. import org . junit . Before ; import org . junit . After ; import org . junit . Test ; import java . util . ArrayList ; import java . util . WeakHashMap ; import java . util . concurrent . atomic . AtomicInteger ; import static org . junit . Assert . * ; public class Memory { static AtomicInteger idx = new AtomicInteger ( 0 ) ; static WeakHashMap < Object , Object > map = new WeakHashMap < Object , Object > ( ) ; int id ; Object obj ; boolean nullify ; public Memory ( ) { super ( ) ; } @ Before public void before ( ) { id = idx . getAndIncrement ( ) ; obj = new Object ( ) ; map . put ( obj , new Object ( ) ) ; System . out . println ( "<BEFORE TEST " + id + ">" ) ; } void test ( boolean n ) { nullify = n ; int before = map . size ( ) ; gc ( ) ; int after = map . size ( ) ; System . out . println ( "BEFORE=" + before + "\tAFTER=" + after ) ; } @ Test public void test0 ( ) { test ( true ) ; }

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