CostEstimator (Ontopia)

java.lang.Object
- net.ontopia.topicmaps.query.impl.utils.CostEstimator

Direct Known Subclasses:

PredicateDrivenCostEstimator, SimpleCostEstimator
```
public abstract class CostEstimator
extends Object
```

Constructor Summary

Constructors
Constructor Description

CostEstimator()

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method	Description
`abstract int`	`computeCost(Set context, AbstractClause clause, Set literalvars, String rulename)`	INTERNAL: Computes the cost of evaluating the given clause in the given context of variable bindings.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - CostEstimator
```
public CostEstimator()
```
- Method Detail
  - computeCost
```
public abstract int computeCost(Set context,
                                AbstractClause clause,
                                Set literalvars,
                                String rulename)
```
    INTERNAL: Computes the cost of evaluating the given clause in the given context of variable bindings. The cost largely depends on the number of unbound variables in the clause.
    
    Parameters:
    
    context - A set of bound variables.
    
    clause - The clause whose cost we want to compute.
    
    literalvars - Contains the variables representing literals. Only an issue in rules.
    
    rulename - The name of the current rule (so we can delay recursive evaluation).