How to handle ordering of @Rule’s when they are dependent on each other

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EDIT: With the recently released Junit 4.10, you can use RuleChain to chain rules correctly (see at the end).

You could introduce another private field without the @Rule annotation, then you can reorder your code as you wish:

public class FolderRuleOrderingTest {

    private TemporaryFolder privateFolder = new TemporaryFolder();

    @Rule
    public MyNumberServer server = new MyNumberServer(privateFolder);

    @Rule
    public TemporaryFolder folder = privateFolder;

    @Test
    public void testMyNumberServer() throws IOException {
        server.storeNumber(10);
        assertEquals(10, server.getNumber());
    }
    ...
}

The cleanest solution is to have a compound rule, but the above should work.

EDIT: With the recently released Junit 4.10, you can use RuleChain to chain rules correctly:

public static class UseRuleChain {
   @Rule
   public TestRule chain = RuleChain
                          .outerRule(new LoggingRule("outer rule"))
                          .around(new LoggingRule("middle rule"))
                          .around(new LoggingRule("inner rule"));

   @Test
   public void example() {
           assertTrue(true);
   }
}

writes the log

starting outer rule
starting middle rule
starting inner rule
finished inner rule
finished middle rule
finished outer rule

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