Package org.eclipse.rdf4j.federated.algebra

## Interface FedXTupleExpr

- All Superinterfaces:
    `Cloneable`, `QueryModelNode`, `QueryRef`, `Serializable`, `TupleExpr`, `VariableExpr`
  All Known Subinterfaces:
    `ExclusiveTupleExpr`, `ExclusiveTupleExprRenderer`, `StatementTupleExpr`
  All Known Implementing Classes:
    `CheckStatementPattern`, `ExclusiveArbitraryLengthPath`, `ExclusiveGroup`, `ExclusiveStatement`, `FedXStatementPattern`, `PassThroughTupleExpr`, `StatementSourcePattern`

      public interface FedXTupleExpr
      extends TupleExpr, VariableExpr, QueryRef

  Interface marking known FedX algebra nodes.
  Author:
    Andreas Schwarte
  See Also:
    `StatementTupleExpr`, `ExclusiveTupleExpr`

- - ### Method Summary

    All Methods Instance Methods Default Methods
    Modifier and Type | Method | Description
    --- | --- | ---
    `default int` | `getFreeVarCount()` |

    - ### Methods inherited from interface org.eclipse.rdf4j.query.algebra.QueryModelNode

      `equals, getCostEstimate, getParentNode, getResultSizeActual, getResultSizeEstimate, getSignature, getTotalTimeNanosActual, replaceChildNode, replaceWith, setCostEstimate, setParentNode, setResultSizeActual, setResultSizeEstimate, setTotalTimeNanosActual, toString, visit, visitChildren`

    - ### Methods inherited from interface org.eclipse.rdf4j.federated.algebra.QueryRef

      `getQueryInfo`

    - ### Methods inherited from interface org.eclipse.rdf4j.query.algebra.TupleExpr

      `clone, getAssuredBindingNames, getBindingNames`

    - ### Methods inherited from interface org.eclipse.rdf4j.federated.algebra.VariableExpr

      `getFreeVars`

- - ### Method Detail

    - #### getFreeVarCount

          default int getFreeVarCount()

      Returns:
        the number of free (i.e. unbound) variables in this expression