@Contract(pure = true)
  @NotNull
  DFAType getNotNullDFAType(int descriptor) {
    DFAType result = getVariableType(descriptor);
    return result == null ? DFAType.NULL_DFA_TYPE : result;
  }
@Contract(pure = true)
  @NotNull
  DFAType getNotNullDFAType(int descriptor)