Class AbstractGridCoverageResource

Object

AbstractResource

AbstractGridCoverageResource

All Implemented Interfaces:

Data­Set, Grid­Coverage­Resource, Resource

Direct Known Subclasses:

Memory­Grid­Coverage­Resource, Tiled­Grid­Coverage­Resource

public abstract class AbstractGridCoverageResource
extends AbstractResource
implements GridCoverageResource

Default implementations of several methods for classes that want to implement the Grid­Coverage­Resource interface. Subclasses should override the following methods:

• Grid­Coverage­Resource.get­Grid­Geometry() (mandatory)
• Grid­Coverage­Resource.get­Sample­Dimensions() (mandatory)

This class also provides the following helper methods for implementation of the read(…) method in subclasses:

• can­Not­Read(String, Grid­Geometry, Throwable) for reporting a failure to read operation.
• log­Read­Operation(Object, Grid­Geometry, long) for logging a notice about a read operation.

Since:

1.2

Nested Class Summary

Nested classes/interfaces inherited from interface Resource

Resource.File­Set

Modifier and Type	Interface	Description
static class	Resource.File­Set	Paths to the files potentially used by the enclosing resource.

Field Summary

Fields inherited from class AbstractResource

listeners

Modifier and Type	Field	Description
protected final Store­Listeners	listeners	The set of registered Store­Listeners for this resources.

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	Abstract­Grid­Coverage­Resource(Store­Listeners parent­Listeners, boolean hidden)	Creates a new resource which can send notifications to the given set of listeners.
protected	Abstract­Grid­Coverage­Resource(Resource parent)	Creates a new resource, potentially as a child of another resource.

Method Summary

Modifier and Type	Method	Description
protected Data­Store­Exception	can­Not­Read(String filename, Grid­Geometry request, Throwable cause)	Creates an exception for a failure to load data.
protected double[]	convert­Resolution­Of(Grid­Geometry domain)	Returns the resolution of the given grid geometry as a resolution in units of this coverage CRS.
protected Metadata	create­Metadata()	Invoked in a synchronized block the first time that get­Metadata() is invoked.
Optional<Envelope>	get­Envelope()	Returns the envelope of the grid geometry if known.
protected void	log­Read­Operation(Object file, Grid­Geometry domain, long start­Time)	Logs the execution of a Grid­Coverage­Resource.read(Grid­Geometry, int...) operation.

Methods inherited from class AbstractResource

add­Listener, clear­Cache, get­Metadata, get­Synchronization­Lock, remove­Listener

Modifier and Type	Method	Description
<T extends Store­Event> void	add­Listener(Class<T> event­Type, Store­Listener<? super T> listener)	Registers a listener to notify when the specified kind of event occurs in this resource or in children.
protected void	clear­Cache()	Clears any cache in this resource, forcing the data to be recomputed when needed again.
final Metadata	get­Metadata()	Returns a description of this resource.
protected Object	get­Synchronization­Lock()	Returns the object on which to perform synchronizations for thread-safety.
<T extends Store­Event> void	remove­Listener(Class<T> event­Type, Store­Listener<? super T> listener)	Unregisters a listener previously added to this resource for the given type of events.

Methods inherited from class Object

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

Methods inherited from interface GridCoverageResource

get­Available­Resolutions, get­Grid­Geometry, get­Loading­Strategy, get­Resolutions, get­Sample­Dimensions, read, set­Loading­Strategy, subset

Modifier and Type	Method	Description
default List<double[]>	get­Available­Resolutions()	Returns the preferred resolutions (in units of CRS axes) for read operations in this data store.
Grid­Geometry	get­Grid­Geometry()	Returns the valid extent of grid coordinates together with the conversion from those grid coordinates to real world coordinates.
default Raster­Loading­Strategy	get­Loading­Strategy()	Returns an indication about when the "physical" loading of raster data will happen.
default List<double[]>	get­Resolutions()	Deprecated, for removal: This API element is subject to removal in a future version. Replaced by Grid­Coverage­Resource.get­Available­Resolutions() but with opposite order.
List<Sample­Dimension>	get­Sample­Dimensions()	Returns the ranges of sample values together with the conversion from samples to real values.
Grid­Coverage	read(Grid­Geometry domain, int... ranges)	Loads a subset of the grid coverage represented by this resource.
default boolean	set­Loading­Strategy(Raster­Loading­Strategy strategy)	Sets the preferred strategy about when to do the "physical" loading of raster data.
default Grid­Coverage­Resource	subset(Query query)	Requests a subset of the coverage.

Methods inherited from interface Resource

get­File­Set, get­Identifier

Modifier and Type	Method	Description
default Optional<Resource.File­Set>	get­File­Set()	Gets the paths to the files potentially used by this resource.
default Optional<Generic­Name>	get­Identifier()	Returns the resource persistent identifier.

Constructor Details

AbstractGridCoverageResource

protected AbstractGridCoverageResource(Resource parent)

Creates a new resource, potentially as a child of another resource. The parent resource is typically, but not necessarily, an Aggregate.

Parameters:

parent - the parent resource, or null if none.

Since:

1.4

AbstractGridCoverageResource

protected AbstractGridCoverageResource(StoreListeners parentListeners,
 boolean hidden)

Creates a new resource which can send notifications to the given set of listeners. The hidden argument specifies whether the new resource should be invisible in the tree of resources. See the parent constructor for more information.

Parameters:

parent­Listeners - listeners of the parent resource, or null if none. This is usually the listeners of the Data­Store that created this resource.

hidden - false if this resource shall use its own Store­Listeners with the specified parent, or true for using parent­Listeners directly.

Method Details

getEnvelope

public Optional<Envelope> getEnvelope()
                               throws DataStoreException

Returns the envelope of the grid geometry if known. The envelope is absent if the grid geometry does not provide this information.

Specified by:

get­Envelope in interface Data­Set

Specified by:

get­Envelope in interface Grid­Coverage­Resource

Overrides:

get­Envelope in class Abstract­Resource

Returns:

the grid geometry envelope.

Throws:

Data­Store­Exception - if an error occurred while computing the grid geometry.

See Also:

• Grid­Geometry.get­Envelope()

createMetadata

protected Metadata createMetadata()
                           throws DataStoreException

Invoked in a synchronized block the first time that get­Metadata() is invoked. The default implementation populates metadata based on information provided by get­Identifier(), get­Envelope(), get­Grid­Geometry() and get­Sample­Dimensions(). Subclasses should override if they can provide more information. The default value can be completed by casting to Default­Metadata.

Overrides:

create­Metadata in class Abstract­Resource

Returns:

the newly created metadata, or null if unknown.

Throws:

Data­Store­Exception - if an error occurred while reading metadata from this resource.

convertResolutionOf

protected double[] convertResolutionOf(GridGeometry domain)
                                throws DataStoreException

Returns the resolution of the given grid geometry as a resolution in units of this coverage CRS. If the CRS of the given domain is equivalent to the CRS of this coverage, then the returned values are equal to domain.get­Resolution(true). Otherwise, a coordinate operation is applied.

This is a helper method for implementations of the read(…) method by subclasses. The argument given to this method is typically the domain argument given to read(…). Subclasses can use the returned values for choosing a subsampling or a pyramid level.

Parameters:

domain - the geometry from which to get the resolution, or null if unspecified.

Returns:

resolution of the given grid geometry in units of this coverage CRS, or null if none.

Throws:

Data­Store­Exception - if an error occurred while converting the domain resolution.

Since:

1.7

See Also:

• Grid­Coverage­Resource.read(Grid­Geometry, int...)
• Grid­Geometry.get­Resolution(boolean)

canNotRead

protected DataStoreException canNotRead(String filename,
 GridGeometry request,
 Throwable cause)

Creates an exception for a failure to load data. The exception sub-type is inferred from the arguments. If the failure is caused by an envelope outside the resource domain, then that envelope will be inferred from the request argument.

Parameters:

filename - some identification (typically a file name) of the data that cannot be read.

request - the requested domain, or null if unspecified.

cause - the cause of the failure, or null if none.

Returns:

the exception to throw.

See Also:

• No­Such­Data­Exception
• Data­Store­Referencing­Exception
• Data­Store­Content­Exception

logReadOperation

protected void logReadOperation(Object file,
 GridGeometry domain,
 long startTime)

Logs the execution of a Grid­Coverage­Resource.read(Grid­Geometry, int...) operation. The log level will be Level.FINE if the operation was quick enough, or Performance­Level.SLOWNESS or higher level otherwise.

Parameters:

file - the file that was opened, or null for Store­Listeners.get­Source­Name().

domain - domain of the created grid coverage.

start­Time - value of System.nano­Time() when the loading process started.