Package org.optaplanner.core.impl.heuristic.selector.value.decorator

## Class CachingValueSelector

- java.lang.Object
- - org.optaplanner.core.impl.heuristic.selector.AbstractSelector
  - - org.optaplanner.core.impl.heuristic.selector.value.AbstractValueSelector
    - - org.optaplanner.core.impl.heuristic.selector.value.decorator.AbstractCachingValueSelector
      - - org.optaplanner.core.impl.heuristic.selector.value.decorator.CachingValueSelector

- All Implemented Interfaces:
    `Iterable<Object>`, `EventListener`, `SelectionCacheLifecycleListener`, `IterableSelector<Object>`, `Selector`, `EntityIndependentValueSelector`, `ValueSelector`, `PhaseLifecycleListener`, `SolverLifecycleListener`

      public class CachingValueSelector
      extends AbstractCachingValueSelector
      implements EntityIndependentValueSelector

  A `ValueSelector` that caches the result of its child `ValueSelector`.

  Keep this code in sync with `CachingEntitySelector` and `CachingMoveSelector`.

- - ### Field Summary

    Fields
    Modifier and Type | Field | Description
    --- | --- | ---
    `protected boolean` | `randomSelection` |

    - ### Fields inherited from class org.optaplanner.core.impl.heuristic.selector.value.decorator.AbstractCachingValueSelector

      `cachedValueList, cacheType, childValueSelector`

    - ### Fields inherited from class org.optaplanner.core.impl.heuristic.selector.AbstractSelector

      `logger, phaseLifecycleSupport, workingRandom`

  - ### Constructor Summary

    Constructors
    Constructor | Description
    --- | ---
    `CachingValueSelector​(EntityIndependentValueSelector childValueSelector, SelectionCacheType cacheType, boolean randomSelection)` |

  - ### Method Summary

    All Methods Instance Methods Concrete Methods
    Modifier and Type | Method | Description
    --- | --- | ---
    `boolean` | `isNeverEnding()` | Is true if `Selector.isCountable()` is false or if this selector is in random order (for most cases).
    `Iterator<Object>` | `iterator()` |
    `Iterator<Object>` | `iterator​(Object entity)` | Similar to `Iterable.iterator()`, but requires an entity.
    `String` | `toString()` |

    - ### Methods inherited from class org.optaplanner.core.impl.heuristic.selector.value.decorator.AbstractCachingValueSelector

      `constructCache, disposeCache, endingIterator, endingIterator, getCacheType, getChildValueSelector, getSize, getSize, getVariableDescriptor, isCountable`

    - ### Methods inherited from class org.optaplanner.core.impl.heuristic.selector.AbstractSelector

      `phaseEnded, phaseStarted, solvingEnded, solvingStarted, stepEnded, stepStarted`

    - ### Methods inherited from class java.lang.Object

      `clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait`

    - ### Methods inherited from interface java.lang.Iterable

      `forEach, spliterator`

    - ### Methods inherited from interface org.optaplanner.core.impl.heuristic.selector.IterableSelector

      `getSize`

    - ### Methods inherited from interface org.optaplanner.core.impl.phase.event.PhaseLifecycleListener

      `phaseEnded, phaseStarted, stepEnded, stepStarted`

    - ### Methods inherited from interface org.optaplanner.core.impl.heuristic.selector.Selector

      `getCacheType, isCountable`

    - ### Methods inherited from interface org.optaplanner.core.impl.solver.event.SolverLifecycleListener

      `solvingEnded, solvingStarted`

    - ### Methods inherited from interface org.optaplanner.core.impl.heuristic.selector.value.ValueSelector

      `endingIterator, getSize, getVariableDescriptor`

- - ### Field Detail

    - #### randomSelection

          protected final boolean randomSelection

  - ### Constructor Detail

    - #### CachingValueSelector

          public CachingValueSelector​(EntityIndependentValueSelector childValueSelector,
                                      SelectionCacheType cacheType,
                                      boolean randomSelection)

  - ### Method Detail

    - #### isNeverEnding

          public boolean isNeverEnding()

      Description copied from interface: `Selector`
      Is true if `Selector.isCountable()` is false or if this selector is in random order (for most cases). Is never true when this selector is in shuffled order (which is less scalable but more exact).
      Specified by:
        `isNeverEnding` in interface `Selector`
      Returns:
        true if the `Iterator.hasNext()` of the `Iterator` created by `Iterable.iterator()` never returns false (except when it's empty).

    - #### iterator

          public Iterator<Object> iterator​(Object entity)

      Description copied from interface: `ValueSelector`
      Similar to `Iterable.iterator()`, but requires an entity.
      Specified by:
        `iterator` in interface `ValueSelector`
      Parameters:
        `entity` - never null
      Returns:
        never null

    - #### iterator

          public Iterator<Object> iterator()

      Specified by:
        `iterator` in interface `Iterable<Object>`

    - #### toString

          public String toString()

      Overrides:
        `toString` in class `Object`