Junit - Multiple @Before vs. one @Before split up into methods

I don't think it makes much of a difference, but I personally prefer the second one (the order Before methods are executed being not defined, you'll have a better control that way).

As has been said in other responses, the order in which JUnit finds methods is not guaranteed, so the execution order of @Before methods can't be guaranteed. The same is true of @Rule, it suffers from the same lack of guarantee. If this will always be the same code, then there isn't any point in splitting into two methods.

If you do have two methods, and more importantly, if you wish to use them from multiple places, then you can combine rules using a RuleChain, which was introduced in 4.10. This allows the specific ordering of rules, such as:

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);
  }
}

This produces:

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

So you can either upgrade to 4.10 or just steal the class.

In your case, you could define two rules, one for client setup and one for object, and combine them in a RuleChain. Using ExternalResource.

public static class UsesExternalResource {
  private TestRule clientRule = new ExternalResource() {
      @Override
      protected void before() throws Throwable {
        setupClientCode();
      };

      @Override
      protected void after() {
        tearDownClientCode()
    };
  };

  @Rule public TestRule chain = RuleChain
                   .outerRule(clientRule)
                   .around(objectRule);
}

So you'll have the following execution order:

clientRule.before()
objectRule.before()
the test
objectRule.after()
clientRule.after()

Note that there are no guarantees about the order in which @Before annotated methods are invoked. If there are some dependencies between them (e.g. one method must be called before the other), you must use the latter form.

Otherwise this is a matter of preference, just keep them in a single place so it is easy to spot them.

I would do the latter. AFAIK, there is no way to guarantee order of @Before annotated setup methods.