public final void init(
      G subjectGenerator, String suiteName, @Nullable Runnable setUp, @Nullable Runnable tearDown) {
    this.subjectGenerator = subjectGenerator;
    this.suiteName = suiteName;
    this.setUp = setUp;
    this.tearDown = tearDown;
  }

  // public so that it can be referenced in generated GWT tests.
  public final void init(G subjectGenerator, String suiteName) {
    init(subjectGenerator, suiteName, null, null);
  }

  public final void init(
      G subjectGenerator, String suiteName, @Nullable Runnable setUp, @Nullable Runnable tearDown) {
    this.subjectGenerator = subjectGenerator;
    this.suiteName = suiteName;
    this.setUp = setUp;
    this.tearDown = tearDown;
  }

  // public so that it can be referenced in generated GWT tests.
  public final void init(G subjectGenerator, String suiteName) {
    init(subjectGenerator, suiteName, null, null);
  }