/// <summary>
/// Process one load specification.
/// </summary>
/// <param name="handler">The data loader that constructs OPL elements.</param>
/// <param name="tuple">The load specification.</param>
private void loadSpec(OplDataHandler handler, ITuple tuple)
{
// Get the connection string
// In the SimpleData implementation we don't use that string.
// If you create a data source that is backed up by a file or
// by a database, then this string can be used to specify
// locations and/or credentials.
string connection = tuple.GetStringValue(CONN_FIELD);
connection = Interpolate(connection, handler);
string connectionType = tryLoadField(tuple, TYPE_FIELD, "SimpleData");
connectionType = Interpolate(connectionType, handler);
IDataProvider provider = null;
if (connectionType.Equals("SimpleData"))
{
provider = new SimpleData(connection);
}
else if (connectionType.Equals("SQLite"))
{
provider = new SQLiteData(connection);
}
else
{
provider = new GenericData(connectionType, connection);
}
// Process each of load specifications and load the respective
// element.
using (provider)
{
ISymbolSet data = tuple.GetSymbolSetValue(DATA_FIELD);
IEnumerator e = data.GetEnumerator();
while (e.MoveNext())
{
// Split specification into element name and
// initialiation string (statement).
string s = Interpolate(e.Current.ToString().Trim(), handler);
int eq = s.IndexOf('=');
string name = s.Substring(0, eq).Trim();
string stmt = s.Substring(eq + 1).Trim();
// Inspect the type of the element and populate it.
OplElement elem = handler.getElement(name);
OplElementType.Type type = elem.ElementType;
using (IEnumerator <IRow> rows = provider.getRows(stmt))
{
// (collections of) integers
if (type == OplElementType.Type.INT)
{
loadPrimitive(handler, name, rows, SET_INT);
}
else if (type == OplElementType.Type.SET_INT)
{
loadPrimitiveCollection(handler, name, rows, START_SET, END_SET, SET_INT);
}
else if (type == OplElementType.Type.MAP_INT)
{
loadPrimitiveCollection(handler, name, rows, START_ARRAY, END_ARRAY, SET_INT);
}
// (collections of) floating point values
else if (type == OplElementType.Type.NUM)
{
loadPrimitive(handler, name, rows, SET_FLOAT);
}
else if (type == OplElementType.Type.SET_NUM)
{
loadPrimitiveCollection(handler, name, rows, START_SET, END_SET, SET_FLOAT);
}
else if (type == OplElementType.Type.MAP_NUM)
{
loadPrimitiveCollection(handler, name, rows, START_ARRAY, END_ARRAY, SET_FLOAT);
}
// (collections of) tuples
else if (type == OplElementType.Type.STRING)
{
loadPrimitive(handler, name, rows, SET_STRING);
}
else if (type == OplElementType.Type.SET_SYMBOL)
{
loadPrimitiveCollection(handler, name, rows, START_SET, END_SET, SET_STRING);
}
else if (type == OplElementType.Type.MAP_SYMBOL)
{
loadPrimitiveCollection(handler, name, rows, START_ARRAY, END_ARRAY, SET_STRING);
}
else if (type == OplElementType.Type.TUPLE)
{
loadTuple(handler, name, rows);
}
else if (type == OplElementType.Type.SET_TUPLE)
{
loadTupleCollection(handler, name, rows, elem.AsTupleSet().Schema, START_SET, END_SET);
}
else if (type == OplElementType.Type.MAP_TUPLE)
{
loadTupleCollection(handler, name, rows, elem.AsTupleMap().Schema, START_ARRAY, END_ARRAY);
}
else
{
throw new NotImplementedException("element type " + type + " not implemented");
}
}
}
}
}