Package org.eclipse.rdf4j.federated.optimizer

## Interface FedXCostModel

- All Known Implementing Classes:
    `DefaultFedXCostModel`

      public interface FedXCostModel

  Interface for a cost model used in `StatementGroupAndJoinOptimizer`.
  Author:
    Andreas Schwarte

- - ### Method Summary

    All Methods Instance Methods Abstract Methods
    Modifier and Type | Method | Description
    --- | --- | ---
    `double` | `estimateCost​(TupleExpr tupleExpr, Set<String> joinVars)` | Return the estimated cost for the given `TupleExpr`

- - ### Method Detail

    - #### estimateCost

          double estimateCost​(TupleExpr tupleExpr,
                              Set<String> joinVars)

      Return the estimated cost for the given `TupleExpr`
      Parameters:
        `tupleExpr` -
        `joinVars` -
      Returns:
        the cost associated to the tupleExpr