public class TLcdGXYCompositeLabelingAlgorithm extends Object implements ILcdGXYLabelingAlgorithm
ILcdGXYLabelingAlgorithms. It works
by assigning labeling algorithms to labels using getLabelingAlgorithmProvider(). Labels
that have the same labeling algorithm are grouped, and then handled by this labeling algorithm.
The order in which the labeling algorithms are executed is determined by the
sortLabelingAlgorithms method. By default it sorts
the labeling algorithms based on the priorities of the labels that are placed by
them. The highest priority of all of its labels is assigned to each labeling algorithm
(see TLcdCollectedLabelInfo.PRIORITY_KEY).
The labeling algorithms are then sorted based on this priority. When two algorithms have the
same priority assigned, the original order in which the algorithms are given is respected.
The default labeling order can be customized by overriding the
sortLabelingAlgorithms method.
The implementation of this labeling algorithm is thread-safe, as long as the set
ILcdGXYLabelLabelingAlgorithmProvider is thread-safe.
| Constructor and Description |
|---|
TLcdGXYCompositeLabelingAlgorithm(ILcdGXYLabelLabelingAlgorithmProvider<? extends ILcdGXYLabelingAlgorithm> aAlgorithmProvider)
Creates a composite labeling algorithm that uses the given
ILcdGXYLabelLabelingAlgorithmProvider
to assign labeling algorithms to labels. |
| Modifier and Type | Method and Description |
|---|---|
TLcdGXYCompositeLabelingAlgorithm |
clone()
Makes
Object.clone() public. |
TLcdCollectedLabelInfoList |
collectLabelInfo(List<TLcdLabelIdentifier> aLabelsToCollect,
Graphics aGraphics,
ILcdGXYView aGXYView)
This method returns a
TLcdCollectedLabelInfoList object based
on the given list of TLcdLabelIdentifiers. |
List<TLcdLabelPlacement> |
computeLabelPlacements(TLcdCollectedLabelInfoList aLabelInfoList,
ILcdLabelConflictChecker aLabelConflictChecker,
ILcdGXYView aView)
This method computes a list of
TLcdLabelPlacements using the given
TLcdCollectedLabelInfoList. |
ILcdGXYLabelLabelingAlgorithmProvider<? extends ILcdGXYLabelingAlgorithm> |
getLabelingAlgorithmProvider()
Returns the used labeling algorithm provider.
|
protected void |
sortLabelingAlgorithms(List<ILcdGXYLabelingAlgorithm> aLabelingAlgorithmsSFCT,
TLcdCollectedLabelInfoList aLabelInfoList)
This method sorts the given
List of labeling algorithms. |
public TLcdGXYCompositeLabelingAlgorithm(ILcdGXYLabelLabelingAlgorithmProvider<? extends ILcdGXYLabelingAlgorithm> aAlgorithmProvider)
ILcdGXYLabelLabelingAlgorithmProvider
to assign labeling algorithms to labels.aAlgorithmProvider - a labeling algorithm provider that returns algorithms for a given label.public ILcdGXYLabelLabelingAlgorithmProvider<? extends ILcdGXYLabelingAlgorithm> getLabelingAlgorithmProvider()
protected void sortLabelingAlgorithms(List<ILcdGXYLabelingAlgorithm> aLabelingAlgorithmsSFCT, TLcdCollectedLabelInfoList aLabelInfoList)
List of labeling algorithms. The labeling algorithms
will be used in this order to place labels. The original order of the labeling algorithms is
determined by the order of the labels in the given TLcdCollectedLabelInfoList.
The default implementation sorts the labeling algorithms based on the priorities of the labels
that are placed by them. The highest priority of all of its labels is assigned to each labeling
algorithm (see TLcdCollectedLabelInfo.PRIORITY_KEY).
The labeling algorithms are then sorted based on this priority. When two algorithms have the
same priority assigned, the original order in which the algorithms are given is respected.
Override this method to provide a custom label placing order.
aLabelingAlgorithmsSFCT - the List of labeling algorithms to be sorted.aLabelInfoList - the label info list containing the labels to be placed the
labeling algorithms in the given List.public TLcdGXYCompositeLabelingAlgorithm clone()
ILcdCloneableMakes Object.clone() public.
java.lang.Object, it can be implemented like this:
public Object clone() {
try {
return super.clone();
} catch ( CloneNotSupportedException e ) {
// Cannot happen: extends from Object and implements Cloneable (see also Object.clone)
throw new RuntimeException( e );
}
}
clone in interface ILcdCloneableclone in class ObjectObject.clone()public TLcdCollectedLabelInfoList collectLabelInfo(List<TLcdLabelIdentifier> aLabelsToCollect, Graphics aGraphics, ILcdGXYView aGXYView)
ILcdGXYLabelingAlgorithmTLcdCollectedLabelInfoList object based
on the given list of TLcdLabelIdentifiers. The returned
TLcdCollectedLabelInfoList should contain a TLcdCollectedLabelInfo
object for each label that should be placed.
Each TLcdCollectedLabelInfo should also contain all information needed by
computeLabelPlacements to place the labels. In order to enable
correct asynchronous label placing, all calls to the layer and the (label) painters should be
done in this method. The results should then be stored in the info objects.
It is possible that the returned TLcdCollectedLabelInfoList doesn't contain a
TLcdCollectedLabelInfo object for every given TLcdLabelIdentifier.
In that case the missing labels are not placed.
collectLabelInfo in interface ILcdGXYLabelingAlgorithmaLabelsToCollect - the labels for which a TLcdCollectedLabelInfoList should
be created.aGraphics - the graphics.aGXYView - the view.TLcdCollectedLabelInfoList which contains all the information needed to
place the labels.public List<TLcdLabelPlacement> computeLabelPlacements(TLcdCollectedLabelInfoList aLabelInfoList, ILcdLabelConflictChecker aLabelConflictChecker, ILcdGXYView aView)
ILcdGXYLabelingAlgorithmTLcdLabelPlacements using the given
TLcdCollectedLabelInfoList. The returned label placements
should contain a valid TLcdLabelLocation and label bounds. They should also point
to their corresponding TLcdCollectedLabelInfo, which in turn should point to its
corresponding TLcdCollectedLabeledObjectInfo.
The given TLcdCollectedLabelInfoList should always be an object created or returned
by collectLabelInfo.
The returned List of TLcdLabelPlacements contains label placements
that are either visible or invisible. When a placement is present in the list, it means that
the location should be stored. When a placement in the list is marked as visible, it means that
its location should be marked as to-be-painted.
The labels should by preference be placed in the order in which the labels are returned by
TLcdCollectedLabelInfoList.getLabels().
computeLabelPlacements in interface ILcdGXYLabelingAlgorithmaLabelInfoList - the info object that contains all information needed to place the labels.aLabelConflictChecker - the bounds conflict checker that can be used to detect conflicts between labels.aView - the view.