/**
* Given the TupleExpr, replace the existence of a UnaryTupleOperator with the provided unary
* operator. If there is nothing in the model that matches, the provided unary operator will be
* placed at the root of the model.
*
* @param theExpr the expression
* @param theNewProj the operator to replace the projectino with
* @return the expression w/ the projection operator removed
*/
public TupleExpr replace(final TupleExpr theExpr, final UnaryTupleOperator theNewProj) {
Visitor aVisitor = new Visitor();
try {
theExpr.visit(aVisitor);
} catch (Exception e) {
// we really should not get an exception here
throw new RuntimeException(e);
}
UnaryTupleOperator aProj = mOperator;
if (aProj == null && insertIfNotPresent) {
theNewProj.setArg(theExpr);
return theNewProj;
} else if (aProj != null && aProj.getParentNode() != null) {
aProj.replaceWith(theNewProj);
return theExpr;
} else if (aProj != null) {
theNewProj.setArg(aProj.getArg());
return theNewProj;
} else {
return theExpr;
}
}
public long getCardinality(UnaryTupleOperator op, BindingSet bindings) {
return getCardinality(op.getArg(), bindings);
}