cdm/src/main/java/ucar/nc2/ncml/Aggregation.java
public void addExplicitDataset(String cacheName, String location, String id, String ncoordS, String coordValueS, String sectionSpec,
                                 ucar.nc2.util.cache.FileFactory reader) {

    Dataset nested = makeDataset(cacheName, location, id, ncoordS, coordValueS, sectionSpec, null, reader);
    explicitDatasets.add(nested);
  }
public void addExplicitDataset(String cacheName, String location, String id, String ncoordS, String coordValueS, String sectionSpec,
                                 ucar.nc2.util.cache.FileFactory reader) {

    Dataset nested = makeDataset(cacheName, location, id, ncoordS, coordValueS, sectionSpec, null, reader);
    explicitDatasets.add(nested);
  }
Add a nested dataset, specified by an explicit netcdf element.
enhance is handled by the reader, so its always false here.

@param cacheName   a unique name to use for caching
@param location    attribute "location" on the netcdf element
@param id          attribute "id" on the netcdf element
@param ncoordS     attribute "ncoords" on the netcdf element
@param coordValueS attribute "coordValue" on the netcdf element
@param sectionSpec attribute "section" on the netcdf element
@param reader      factory for reading this netcdf dataset