com.luciad.fusion.tilestore.metadata

LuciadLightspeedClass ALfnResourceMetadata

java.lang.Object

com.luciad.fusion.tilestore.metadata.ALfnResourceMetadata

Direct Known Subclasses:

ALfnAssetMetadata, ALfnCoverageMetadata, TLfnThemeMetadata

public abstract class ALfnResourceMetadata
extends Object

An abstract representation of a resource. The resource metadata contains the following parameters:

• ID: a unique identifier for a resource, it must be specified and must not be null
• name: a (human-readable) name for a resource, defaults to null if unspecified
• abstract: an abstract (short description) of an asset (optional, defaults to null if unspecified)
• update sequence: a version for a resource's metadata, defaults to NEW_UPDATE_SEQUENCE if unspecified. The update sequence increases whenever a resource's metadata is modified; it is used to check for concurrent modifications. A higher update sequence indicates a more recent version
• ISO 19115 metadata: ISO 19115 metadata for a resource, defaults to null if unspecified

Instances of this class are immutable and thus thread-safe.

This class and its subclasses implement a Builder design pattern: the resource metadata is immutable and cannot be instantiated directly. Instantiation and modification should go via a corresponding builder. Also a builder cannot be instantiated directly, it must be created via a static factory method on the concrete subclasses.

This class and its subclasses implement a Visitor design pattern, see ALfnResourceMetadataVisitor.

The properties of resource metadata can be queried using OGC Filters, via ALfnTileStore.query(com.luciad.fusion.tilestore.ILfnQueryHandler, com.luciad.fusion.tilestore.TLfnQuery). The OGC Filter XPath expression corresponding to a property is documented with each getter.
The XML namespace prefixes used in the documentation are as follows:

• lts: the Luciad Tile Store namespace
• xlink: the XML Linking Language namespace
• gmd: the ISO 19115 Geographic Metadata namespace
• gco: the ISO 19115 Geographic Common namespace

Please refer to the XPath 1.0 specification for more information on XPath expressions.

Since:

10.0

See Also:

ALfnResourceMetadata.Builder

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	ALfnResourceMetadata.Builder<B extends ALfnResourceMetadata.Builder<B>> Abstract builder for resource metadata.

Field Summary

Fields

Modifier and Type	Field and Description
static String	ISO19115_GCO_XML_NAMESPACE XML namespace for ISO19115 Geographic Common elements.
static String	ISO19115_GMD_XML_NAMESPACE XML namespace for ISO19115 Geographic Metadata elements.
static String	LTS_XML_NAMESPACE XML namespace for Luciad Tile Store elements.
static long	NEW_UPDATE_SEQUENCE Update sequence for a new or unknown resource.
static String	XLINK_XML_NAMESPACE XML namespace for xlink elements.

Method Summary

Modifier and Type	Method and Description
abstract void	accept(ALfnResourceMetadataVisitor aVisitor) Accepts the visitor for visiting this resource.
abstract ALfnResourceMetadata.Builder<?>	asBuilder() Creates a new builder from this resource metadata.
boolean	equals(Object aObject)
String	getAbstract() Gets the abstract of this asset.
long	getGlobalUpdateSequence() Returns a number representing when the data was last modified.
String	getId() Gets the ID of this resource, which is never null.
TLcdISO19115Metadata	getISO19115Metadata() Gets the ISO 19115 metadata of this resource, or null if none.
String	getName() Gets the name of this resource, or null if none.
long	getUpdateSequence() Gets the update sequence (version) of this resource, which is never negative.
int	hashCode()
String	toString() Gets the ID of this resource as a string representation.

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

LTS_XML_NAMESPACE

public static final String LTS_XML_NAMESPACE

XML namespace for Luciad Tile Store elements. This constant points to the current LTS version, and may change in future releases when a newer protocol version becomes available.

See Also:

Constant Field Values

XLINK_XML_NAMESPACE

public static final String XLINK_XML_NAMESPACE

XML namespace for xlink elements.

See Also:

Constant Field Values

ISO19115_GMD_XML_NAMESPACE

public static final String ISO19115_GMD_XML_NAMESPACE

XML namespace for ISO19115 Geographic Metadata elements.

See Also:

Constant Field Values

ISO19115_GCO_XML_NAMESPACE

public static final String ISO19115_GCO_XML_NAMESPACE

XML namespace for ISO19115 Geographic Common elements.

See Also:

Constant Field Values

NEW_UPDATE_SEQUENCE

public static final long NEW_UPDATE_SEQUENCE

Update sequence for a new or unknown resource.

See Also:

Constant Field Values

Method Detail

getId

public final String getId()

Gets the ID of this resource, which is never null. The default ID is a UUID.

OGC filter property XPath: @id
ID query is also supported directly using the OGC Filter object ID query.

Returns:

the ID of this resource

getName

public final String getName()

Gets the name of this resource, or null if none.

OGC filter property XPath: lts:Name

Returns:

the name of this resource, or null if none

getAbstract

public String getAbstract()

Gets the abstract of this asset.

OGC filter property XPath: lts:Abstract

Returns:

the abstract, or null if unspecified

getUpdateSequence

public final long getUpdateSequence()

Gets the update sequence (version) of this resource, which is never negative. The default update sequence is 0.

OGC filter property XPath: @updateSequence

Returns:

the update sequence (version) of this resource

getISO19115Metadata

public TLcdISO19115Metadata getISO19115Metadata()

Gets the ISO 19115 metadata of this resource, or null if none.

OGC filter property XPath: gmd:MD_Metadata
Please refer to the ISO 19139:2007 specification for the XML schemas of ISO 19115 metadata.
Sample XPaths:

• The language of the metadata: /gmd:MD_Metadata/gmd:language/gco:CharacterString
• The individual's name of a responsible party: //gmd:CI_ResponsibleParty/gmd:individualName/gco:CharacterString
• The security classification of a metadata: //gmd:MD_ClassificationCode

Returns:

the ISO 19115 metadata, or null if none

getGlobalUpdateSequence

public final long getGlobalUpdateSequence()

Returns a number representing when the data was last modified.

A resource has a unique identifier across all tile stores (the getId()) indicating/identifying the resource. When a resource is updated (e.g. more recent data became available), the identifier remains unchanged. In order to indicate that the updated resource is a "newer" version of the same data, the last modified number of the updated resource will be larger then the modified number of the original resource.

This mechanism allows to compare two tile stores and identify for each resource:

• Whether the resource is present on both tile stores or not, based on the getId().
• When the resource is present on both tile stores, which of the two is the most recent one.

This number is automatically managed by LuciadFusion. While there is a method available on the Builder, you are not supposed to call this method yourself.

Note that this is not the same as the update sequence. The update sequence is a tile store specific version number and cannot be used to compare resource versions across different tile stores.

Returns:

a number indicating when the resource was last modified.

Since:

2015.0

equals

public boolean equals(Object aObject)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object

toString

public final String toString()

Gets the ID of this resource as a string representation.

Overrides:

toString in class Object

Returns:

the ID of this resource as a string representation

accept

public abstract void accept(ALfnResourceMetadataVisitor aVisitor)

Accepts the visitor for visiting this resource. This provides a double-dispatch.

Parameters:

aVisitor - the visitor

See Also:

ALfnResourceMetadataVisitor

asBuilder

public abstract ALfnResourceMetadata.Builder<?> asBuilder()

Creates a new builder from this resource metadata. The builder's fields are initialized to the values of this resource metadata. The builder will build a resource metadata of the same type as this instance.

Returns:

a new builder

Since:

11.0