private ImmutableSet<String> getImports(Class<?>... classes) {
    ImmutableSet.Builder<String> stringBuilder = ImmutableSortedSet.naturalOrder();
    for (Class<?> clazz : classes) {
      stringBuilder.add("import " + clazz.getName() + ";");
    }
    return stringBuilder.build();
  }
Tests to ensure annotations are kept on AutoValue generated classes

@author jmcampanini
value/src/test/java/com/google/auto/value/processor/PropertyAnnotationsTest.java