public PsiType @NotNull [] inferParameters() {
    final PsiClass psiClass = resolve();
    if (psiClass != null && psiClass.getTypeParameters().length == 1) {
      final PsiType type = GrClosureSignatureUtil.getReturnType(mySignatures);
      if (type == PsiTypes.nullType() || type == null) {
        return new PsiType[]{null};
      }
      else {
        return new PsiType[]{TypesUtil.boxPrimitiveType(type, getPsiManager(), getResolveScope(), true)};
      }
    }
    else {
      return PsiType.EMPTY_ARRAY;
    }
  }
public PsiType @NotNull [] inferParameters()