/// <summary>
/// Factory method.
/// </summary>
/// <param name="type"> A type of the clause to build. </param>
/// <param name="graph"> A graph to conduct computation on. </param>
/// <param name="helper"> A helper that contains information about execution. </param>
/// <param name="map"> A map of variables. </param>
/// <param name="parseTree"> A parsed tree to create the clause from. </param>
/// <param name="exprInfo"> A query expression information. </param>
public static QueryObject Factory(Type type, Graph graph, QueryExecutionHelper helper, VariableMap map, Node parseTree, QueryExpressionInfo exprInfo)
{
if (type == typeof(SelectObject))
{
return(new SelectObject(graph, map, helper, (SelectNode)parseTree, exprInfo));
}
else if (type == typeof(MatchObject))
{
return(new MatchObject(graph, map, helper, (MatchNode)parseTree, exprInfo));
}
else if (type == typeof(MatchObjectStreamed))
{
return(new MatchObjectStreamed(graph, map, helper, (MatchNode)parseTree, exprInfo));
}
else if (type == typeof(OrderByObject))
{
return(new OrderByObject(graph, map, helper, (OrderByNode)parseTree, exprInfo));
}
else if (type == typeof(GroupByObject) && graph == null && map == null && parseTree == null)
{
return(new GroupByObject(helper, exprInfo));
}
else if (type == typeof(GroupByObject))
{
return(new GroupByObject(graph, map, helper, (GroupByNode)parseTree, exprInfo));
}
else
{
throw new ArgumentException($"Query object factory, cannot create type {type}.");
}
}
/// <summary>
/// Builds a query from an input.
/// Cannot contain order by and group by simultaneously.
/// Called by static Create method.
/// </summary>
/// <param name="tokens"> An input query. </param>
/// <param name="graph"> A graph to compute the query on. </param>
/// <param name="threadCount"> Maximum number of threads available to use. </param>
/// <param name="printer"> A printer to use. </param>
/// <param name="formater"> A formater to use by printer. </param>
/// <param name="verticesPerThread"> A number of vertices distributed to threads during parallel computation of the query.</param>
/// <param name="fileName"> A file to store results into if set, otherwise null. </param>
/// <param name="allowPrint"> Whether to allow printing. Mainly for benchmarking purposes.</param>
/// <param name="fixedArraySize"> The size of the arrays used for storing results of the matcher.</param>
/// <param name="grouperAlias"> A grouper to use when specifying group by.</param>
/// <param name="sorterAlias"> A sorter to use when specifying order by.</param>
private Query(List <Token> tokens, Graph graph, bool allowPrint, int threadCount, PrinterType printer, FormaterType formater, int verticesPerThread, string fileName, GrouperAlias grouperAlias, SorterAlias sorterAlias, int fixedArraySize)
{
this.graph = graph;
this.variableMap = new VariableMap();
this.qEhelper = new QueryExecutionHelper(threadCount, printer, formater, verticesPerThread, fixedArraySize, fileName, "DFSParallel", "DFSSingleThread", "SIMPLE", grouperAlias, sorterAlias);
// Parse input query.
var parsedClauses = Parser.Parse(tokens);
// Create execution chain.
if (parsedClauses.ContainsKey(Parser.Clause.GroupBy) && parsedClauses.ContainsKey(Parser.Clause.OrderBy))
{
throw new ArgumentException($"{this.GetType()}, the query cannot contain both order by and group by");
}
QueryObject groupBy = null;
QueryObject orderBy = null;
// MATCH is always leaf.
QueryObject match = QueryObject.Factory
(typeof(MatchObject), graph, qEhelper, variableMap, parsedClauses[Parser.Clause.Match], null);
// Second must be group by because it defines what can be in other clauses.
// GROUP BY
if (parsedClauses.ContainsKey(Parser.Clause.GroupBy))
{
this.exprInfo = new QueryExpressionInfo(true);
groupBy = QueryObject.Factory(typeof(GroupByObject), graph, qEhelper, variableMap, parsedClauses[Parser.Clause.GroupBy], exprInfo);
}
else
{
this.exprInfo = new QueryExpressionInfo(false);
}
// SELECT is the last one to process the resuls.
this.query = QueryObject.Factory
(typeof(SelectObject), graph, qEhelper, variableMap, parsedClauses[Parser.Clause.Select], exprInfo);
((SelectObject)this.query).allowPrint = allowPrint;
// Check if the results are in a single group.
this.SetSingleGroupFlags();
// ORDER BY
if (parsedClauses.ContainsKey(Parser.Clause.OrderBy))
{
orderBy = QueryObject.Factory(typeof(OrderByObject), graph, qEhelper, variableMap, parsedClauses[Parser.Clause.OrderBy], exprInfo);
query.AddToEnd(orderBy);
}
// If the single group by is set, add GroupBy object to the execution chain.
if (this.qEhelper.IsSetSingleGroupGroupBy && !this.qEhelper.IsSetGroupBy)
{
groupBy = QueryObject.Factory(typeof(GroupByObject), null, qEhelper, null, null, exprInfo);
}
if (groupBy != null)
{
query.AddToEnd(groupBy);
}
query.AddToEnd(match);
query.PassStoringVariables(this.exprInfo.CollectUsedVariables());
}
public ExpressionVisitor(Dictionary <string, Tuple <int, Type> > labels, VariableMap map, QueryExpressionInfo exprInfo)
{
this.variableMap = map;
this.labels = labels;
this.exprInfo = exprInfo;
}
