AlterSpyPoint

java.lang.Object
- org.projog.core.predicate.AbstractSingleResultPredicate
- - org.projog.core.predicate.builtin.debug.AlterSpyPoint

All Implemented Interfaces:

KnowledgeBaseConsumer, PredicateFactory
```
public final class AlterSpyPoint
extends AbstractSingleResultPredicate
```
spy(X) / nospy(X) - add or remove a spy point for a predicate.
spy(X) - add a spy point for a predicate. By adding a spy point for the predicate name instantiated to X the programmer will be informed how it is used in the resolution of a goal.

nospy(X) - removes a spy point for a predicate. By removing a spy point for the predicate name instantiated to X the programmer will no longer be informed how it is used in the resolution of a goal.

Field Summary

Fields
Modifier and Type Field Description

private boolean valueToSetSpyPointTo

Constructor Summary

Constructors
Modifier	Constructor	Description
`private`	`AlterSpyPoint(boolean valueToSetSpyPointTo)`	The `valueToSetSpyPointTo` parameter specifies whether spy points matched by the `evaluate(Term)` method should be enabled or disabled.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`protected boolean`	`evaluate(Term t)`
`static AlterSpyPoint`	`noSpy()`
`private void`	`setSpyPoint(PredicateKey key)`
`private void`	`setSpyPoints(java.util.List<PredicateKey> keys)`
`static AlterSpyPoint`	`spy()`

Methods inherited from class org.projog.core.predicate.AbstractSingleResultPredicate
evaluate, evaluate, evaluate, evaluate, evaluate, getArithmeticOperators, getFileHandles, getKnowledgeBase, getOperands, getPredicate, getPredicates, getProjogListeners, getSpyPoints, getTermFormatter, init, isRetryable, setKnowledgeBase

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

Methods inherited from interface org.projog.core.predicate.PredicateFactory
isAlwaysCutOnBacktrack

- Field Detail
  - valueToSetSpyPointTo
```
private final boolean valueToSetSpyPointTo
```
- Constructor Detail
  - AlterSpyPoint
```
private AlterSpyPoint(boolean valueToSetSpyPointTo)
```
    The valueToSetSpyPointTo parameter specifies whether spy points matched by the evaluate(Term) method should be enabled or disabled.
    
    Parameters:
    
    valueToSetSpyPointTo - true to enable spy points, false to disable spy points
- Method Detail
  - spy
```
public static AlterSpyPoint spy()
```
  - noSpy
```
public static AlterSpyPoint noSpy()
```
  - evaluate
```
protected boolean evaluate(Term t)
```
    Overrides:
    
    evaluate in class AbstractSingleResultPredicate
  - setSpyPoints
```
private void setSpyPoints(java.util.List<PredicateKey> keys)
```
  - setSpyPoint
```
private void setSpyPoint(PredicateKey key)
```