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

## Class FromSolutionPropertyValueSelector

- 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.FromSolutionPropertyValueSelector

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

      public class FromSolutionPropertyValueSelector
      extends AbstractValueSelector
      implements EntityIndependentValueSelector

  This is the common `ValueSelector` implementation.

- - ### Field Summary

    Fields
    Modifier and Type | Field | Description
    --- | --- | ---
    `protected boolean` | `cachedEntityListIsDirty` |
    `protected Long` | `cachedEntityListRevision` |
    `protected ValueRange<Object>` | `cachedValueRange` |
    `protected SelectionCacheType` | `minimumCacheType` |
    `protected boolean` | `randomSelection` |
    `protected EntityIndependentValueRangeDescriptor` | `valueRangeDescriptor` |
    `protected boolean` | `valueRangeMightContainEntity` |

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

      `logger, phaseLifecycleSupport, workingRandom`

  - ### Constructor Summary

    Constructors
    Constructor | Description
    --- | ---
    `FromSolutionPropertyValueSelector​(EntityIndependentValueRangeDescriptor valueRangeDescriptor, SelectionCacheType minimumCacheType, boolean randomSelection)` |

  - ### Method Summary

    All Methods Instance Methods Concrete Methods
    Modifier and Type | Method | Description
    --- | --- | ---
    `Iterator<Object>` | `endingIterator()` |
    `Iterator<Object>` | `endingIterator​(Object entity)` | If `Selector.isNeverEnding()` is true, then `ValueSelector.iterator(Object)` will never end.
    `SelectionCacheType` | `getCacheType()` | Unless this selector itself caches, this returns `SelectionCacheType.JUST_IN_TIME`, even if a selector child caches.
    `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`.
    `long` | `getSize​(Object entity)` | Similar to `IterableSelector.getSize()`, but requires an entity.
    `GenuineVariableDescriptor` | `getVariableDescriptor()` |
    `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()` |
    `Iterator<Object>` | `iterator​(Object entity)` | Similar to `Iterable.iterator()`, but requires an entity.
    `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

    - #### valueRangeDescriptor

          protected final EntityIndependentValueRangeDescriptor valueRangeDescriptor

    - #### minimumCacheType

          protected final SelectionCacheType minimumCacheType

    - #### randomSelection

          protected final boolean randomSelection

    - #### valueRangeMightContainEntity

          protected final boolean valueRangeMightContainEntity

    - #### cachedValueRange

          protected ValueRange<Object> cachedValueRange

    - #### cachedEntityListRevision

          protected Long cachedEntityListRevision

    - #### cachedEntityListIsDirty

          protected boolean cachedEntityListIsDirty

  - ### Constructor Detail

    - #### FromSolutionPropertyValueSelector

          public FromSolutionPropertyValueSelector​(EntityIndependentValueRangeDescriptor valueRangeDescriptor,
                                                   SelectionCacheType minimumCacheType,
                                                   boolean randomSelection)

  - ### Method Detail

    - #### getVariableDescriptor

          public GenuineVariableDescriptor getVariableDescriptor()

      Specified by:
        `getVariableDescriptor` in interface `ValueSelector`
      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

    - #### 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.
      Specified by:
        `isCountable` in interface `Selector`
      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).
      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).

    - #### getSize

          public long getSize​(Object entity)

      Description copied from interface: `ValueSelector`
      Similar to `IterableSelector.getSize()`, but requires an entity.
      Specified by:
        `getSize` in interface `ValueSelector`
      Parameters:
        `entity` - never null
      Returns:
        the approximate number of elements generated by this `Selector`, always `>= 0`

    - #### 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`.
      Specified by:
        `getSize` in interface `IterableSelector<Object>`
      Returns:
        the approximate number of elements generated by this `Selector`, always `>= 0`

    - #### 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>`

    - #### endingIterator

          public Iterator<Object> endingIterator​(Object entity)

      Description copied from interface: `ValueSelector`
      If `Selector.isNeverEnding()` is true, then `ValueSelector.iterator(Object)` will never end. This returns an ending `Iterator`, that tries to match `ValueSelector.iterator(Object)` as much as possible, but return each distinct element only once and therefore it might not respect the configuration of this `ValueSelector` entirely.
      Specified by:
        `endingIterator` in interface `ValueSelector`
      Parameters:
        `entity` - never null
      Returns:
        never null
      See Also:
        `ValueSelector.iterator(Object)`

    - #### endingIterator

          public Iterator<Object> endingIterator()

    - #### toString

          public String toString()

      Overrides:
        `toString` in class `Object`