Package org.optaplanner.core.impl.heuristic.selector.entity

## Class FromSolutionEntitySelector

- java.lang.Object
- - org.optaplanner.core.impl.heuristic.selector.AbstractSelector
  - - org.optaplanner.core.impl.heuristic.selector.entity.AbstractEntitySelector
    - - org.optaplanner.core.impl.heuristic.selector.entity.FromSolutionEntitySelector

- All Implemented Interfaces:
    `Iterable<Object>`, `EventListener`, `ListIterable<Object>`, `EntitySelector`, `IterableSelector<Object>`, `ListIterableSelector<Object>`, `Selector`, `PhaseLifecycleListener`, `SolverLifecycleListener`

      public class FromSolutionEntitySelector
      extends AbstractEntitySelector

  This is the common `EntitySelector` implementation.

- - ### Field Summary

    Fields
    Modifier and Type | Field | Description
    --- | --- | ---
    `protected List<Object>` | `cachedEntityList` |
    `protected boolean` | `cachedEntityListIsDirty` |
    `protected Long` | `cachedEntityListRevision` |
    `protected EntityDescriptor` | `entityDescriptor` |
    `protected SelectionCacheType` | `minimumCacheType` |
    `protected boolean` | `randomSelection` |

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

      `logger, phaseLifecycleSupport, workingRandom`

  - ### Constructor Summary

    Constructors
    Constructor | Description
    --- | ---
    `FromSolutionEntitySelector​(EntityDescriptor entityDescriptor, SelectionCacheType minimumCacheType, boolean randomSelection)` |

  - ### Method Summary

    All Methods Instance Methods Concrete Methods
    Modifier and Type | Method | Description
    --- | --- | ---
    `Iterator<Object>` | `endingIterator()` | If `Selector.isNeverEnding()` is true, then `Iterable.iterator()` will never end.
    `SelectionCacheType` | `getCacheType()` | Unless this selector itself caches, this returns `SelectionCacheType.JUST_IN_TIME`, even if a selector child caches.
    `EntityDescriptor` | `getEntityDescriptor()` |
    `long` | `getSize()` | A random JIT `Selector` with `Selector.isNeverEnding()` true should return a size as if it would be able to return each distinct element only once, because the size can be used in `SelectionProbabilityWeightFactory`.
    `boolean` | `isCountable()` | If false, then `Selector.isNeverEnding()` is true.
    `boolean` | `isNeverEnding()` | Is true if `Selector.isCountable()` is false or if this selector is in random order (for most cases).
    `Iterator<Object>` | `iterator()` |
    `ListIterator<Object>` | `listIterator()` |
    `ListIterator<Object>` | `listIterator​(int index)` |
    `void` | `phaseEnded​(AbstractPhaseScope phaseScope)` |
    `void` | `phaseStarted​(AbstractPhaseScope phaseScope)` |
    `void` | `stepStarted​(AbstractStepScope stepScope)` |
    `String` | `toString()` |

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

      `solvingEnded, solvingStarted, stepEnded`

    - ### 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.phase.event.PhaseLifecycleListener

      `stepEnded`

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

      `solvingEnded, solvingStarted`

- - ### Field Detail

    - #### entityDescriptor

          protected final EntityDescriptor entityDescriptor

    - #### minimumCacheType

          protected final SelectionCacheType minimumCacheType

    - #### randomSelection

          protected final boolean randomSelection

    - #### cachedEntityList

          protected List<Object> cachedEntityList

    - #### cachedEntityListRevision

          protected Long cachedEntityListRevision

    - #### cachedEntityListIsDirty

          protected boolean cachedEntityListIsDirty

  - ### Constructor Detail

    - #### FromSolutionEntitySelector

          public FromSolutionEntitySelector​(EntityDescriptor entityDescriptor,
                                            SelectionCacheType minimumCacheType,
                                            boolean randomSelection)

  - ### Method Detail

    - #### getEntityDescriptor

          public EntityDescriptor getEntityDescriptor()

      Returns:
        never null

    - #### getCacheType

          public SelectionCacheType getCacheType()

      Description copied from interface: `Selector`
      Unless this selector itself caches, this returns `SelectionCacheType.JUST_IN_TIME`, even if a selector child caches.
      Specified by:
        `getCacheType` in interface `Selector`
      Overrides:
        `getCacheType` in class `AbstractSelector`
      Returns:
        never null, at least `SelectionCacheType.STEP`

    - #### phaseStarted

          public void phaseStarted​(AbstractPhaseScope phaseScope)

      Specified by:
        `phaseStarted` in interface `PhaseLifecycleListener`
      Overrides:
        `phaseStarted` in class `AbstractSelector`

    - #### stepStarted

          public void stepStarted​(AbstractStepScope stepScope)

      Specified by:
        `stepStarted` in interface `PhaseLifecycleListener`
      Overrides:
        `stepStarted` in class `AbstractSelector`

    - #### phaseEnded

          public void phaseEnded​(AbstractPhaseScope phaseScope)

      Specified by:
        `phaseEnded` in interface `PhaseLifecycleListener`
      Overrides:
        `phaseEnded` in class `AbstractSelector`

    - #### isCountable

          public boolean isCountable()

      Description copied from interface: `Selector`
      If false, then `Selector.isNeverEnding()` is true.
      Returns:
        true if all the `ValueRange`s are countable (for example a double value range between 1.2 and 1.4 is not countable)

    - #### 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).
      Returns:
        true if the `Iterator.hasNext()` of the `Iterator` created by `Iterable.iterator()` never returns false (except when it's empty).

    - #### getSize

          public long getSize()

      Description copied from interface: `IterableSelector`
      A random JIT `Selector` with `Selector.isNeverEnding()` true should return a size as if it would be able to return each distinct element only once, because the size can be used in `SelectionProbabilityWeightFactory`.
      Returns:
        the approximate number of elements generated by this `Selector`, always `>= 0`

    - #### iterator

          public Iterator<Object> iterator()

    - #### listIterator

          public ListIterator<Object> listIterator()

      Returns:
        never null, see `List.listIterator()`.
      See Also:
        `List.listIterator()`

    - #### listIterator

          public ListIterator<Object> listIterator​(int index)

      Parameters:
        `index` - lower than the size of this `ListIterable`, see `List.listIterator(int)`.
      Returns:
        never null, see `List.listIterator(int)`.
      See Also:
        `List.listIterator()`

    - #### endingIterator

          public Iterator<Object> endingIterator()

      Description copied from interface: `EntitySelector`
      If `Selector.isNeverEnding()` is true, then `Iterable.iterator()` will never end. This returns an ending `Iterator`, that tries to match `Iterable.iterator()` as much as possible, but returns each distinct element only once and returns every element that might possibly be selected and therefore it might not respect the configuration of this `EntitySelector` entirely.
      Returns:
        never null
      See Also:
        `Iterable.iterator()`

    - #### toString

          public String toString()

      Overrides:
        `toString` in class `Object`