Use of ArrayString, or Lack Thereof

[rschmunk]

Is the ArrayString class used anywhere other than one of the test classes?

I was trying to figure out why calling Variable.getArray() on a single-valued String variable was returning an ArrayObject.D0 rather than, as I would have guessed, and ArrayString.D0. After delving into the code it looks to me that the only place where an ArrayString object is ever created is in TestNc4Structures.

It's easy enough to call ArrayObject.D0.get() to retrieve the actual String, but I was surprised that the ArrayString class even exists as it's essentially never used. Should I have been?

[lesserwhirls]

I'll leave this open for a bit in case someone with more historical context wants to chime in, but my guess is that using Object[] as the backing store (and casting when reading elements) for non-primitive data types has a lower overhead than using an appropriate concrete class like String[]. If you check out Variable.readScalarString():

  public String readScalarString() throws IOException {
    Array data = _readScalarData();
    if (dataType == DataType.STRING)
      return (String) data.getObject(Index.scalarIndexImmutable);
    else if (dataType == DataType.CHAR) {
      ArrayChar dataC = (ArrayChar) data;
      return dataC.getString();
    } else
      throw new IllegalArgumentException("readScalarString not STRING or CHAR " + getFullName());
  }

that's what it is doing. What I don't see is some kind of friendly helper for non-scalar arrays (in Variable or ArrayObject).