public PdfIndirectReference add(PdfIndirectReference reference){
  if (reference == null) {
    return null;
  }
  int objNr=reference.getObjNumber();
  this.count=Math.max(this.count,objNr);
  ensureCount(objNr);
  xref[objNr]=reference;
  return reference;
}

public PdfIndirectReference add ( PdfIndirectReference reference ) { if ( reference == null ) { return null ; } int objNr = reference . getObjNumber ( ) ; this . count = Math . max ( this . count , objNr ) ; ensureCount ( objNr ) ; xref [ objNr ] = reference ; return reference ; }
adds indirect reference to list of indirect objects .
