The class javadoc for PointArray current states:
The PointArray interface outlines a means of efficiently storing large numbers of <b>usually</b> homogeneous Position positions; i.e. all having the same CoordinateReferenceSystem coordinate reference system.</blockquote>
I would like to change that language to <b>require</b> the structure to have a homogenous set of CRS's either explicitly or, for situations where the DirectPosition set does not have an actual reference to the CRS, implicitly. There are alternative data structures such as the generic List<Position>, which a user could leverage to store and exchange mixed bags of Positions. PointArray, as defined in GeoAPI, potentially has its own information, i.e. a CRS, so the interface only makes sense with reference to a homogenous set of Positions.