public abstract class InfoToolHelper extends Object implements MapBoundsListener
Modifier and Type | Field and Description |
---|---|
protected WeakReference<MapContent> |
contentRef |
static String |
KEY_POSITION
String key used for the position element in the
Map passed to #getInfo(
org.geotools.util.KVP ). |
protected WeakReference<Layer> |
layerRef |
Constructor and Description |
---|
InfoToolHelper() |
Modifier and Type | Method and Description |
---|---|
protected void |
clearTransform() |
protected MathTransform |
getContentToLayerTransform()
Gets the
MathTransform used to convert coordinates from the projection being used by
the MapContent to that of the Layer . |
abstract InfoToolResult |
getInfo(DirectPosition2D pos)
Gets layer data at the specified position.
|
Layer |
getLayer()
Gets the map layer associated with this helper.
|
MapContent |
getMapContent()
Gets the map content associated with this helper.
|
abstract boolean |
isSupportedLayer(Layer layer)
CAlled by the helper lookup system when selecting a helper for a given layer.
|
protected boolean |
isTransformRequired() |
boolean |
isValid()
Checks if this helper is holding a reference to a
MapContent and a Layer .Helpers only hold a WeakReference to both the map content and layer to avoid
blocking garbage collection when layers are discarded. |
void |
mapBoundsChanged(MapBoundsEvent event)
A method from the
MapBoundsListener interface used to listen for a change to the map
content's coordinate reference system. |
void |
setLayer(Layer layer)
Sets the map layer for this helper.
|
void |
setMapContent(MapContent content)
Sets the map content for this helper.
|
public static final String KEY_POSITION
Map
passed to #getInfo(
org.geotools.util.KVP ).protected WeakReference<MapContent> contentRef
protected WeakReference<Layer> layerRef
public abstract boolean isSupportedLayer(Layer layer)
layer
- the layertrue
is this helper can handle the layerIllegalArgumentException
- if layer
is null
public abstract InfoToolResult getInfo(DirectPosition2D pos) throws Exception
InfoToolResult
object is returned.pos
- query positionException
- on error querying the layerpublic boolean isValid()
MapContent
and a Layer
.Helpers only hold a WeakReference
to both the map content and layer to avoid
blocking garbage collection when layers are discarded.true
if both map content and layer references are validpublic void setMapContent(MapContent content)
layer
- the map contentIllegalArgumentException
- if content
is null
public MapContent getMapContent()
public void setLayer(Layer layer)
layer
- the map layerIllegalArgumentException
- if layer
is null
public Layer getLayer()
public void mapBoundsChanged(MapBoundsEvent event)
MapBoundsListener
interface used to listen for a change to the map
content's coordinate reference system.mapBoundsChanged
in interface MapBoundsListener
event
- The change event.protected MathTransform getContentToLayerTransform()
MathTransform
used to convert coordinates from the projection being used by
the MapContent
to that of the Layer
.null
if the layer's CRS is the same as that of the map
content, or if either has no CRS definedprotected boolean isTransformRequired()
protected void clearTransform()
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