CatalogQuery Class

A class used to query a Catalog for available maps and data sets.

Syntax

public class CatalogQuery : ResourceObject

Remarks

This class is used to specify search parameters when querying for catalog maps and data sets with Catalog.GetMaps and Catalog.GetDataSets. Each metadata record in the catalog matching this query will be returned.

The query is specified as a string expression, using the same syntax as for example the Condition class. For each metadata record in catalog, an AttributeSet is created with all searchable attributes from the metadata. This attribute set is used to evaluate the expression.

The expressions are quite powerful and can test complex combinations of metadata values. Below a few simple examples are shown. For a full description of the expression format, please see Expression Syntax.

Query String	Result
true	All services will match the query.
name = "WorldMap"	Services with the name WorldMap will match the query.
language = "eng"	All services with the language English set will match the query.

The following table shows the attributes that may be available in the attribute set. Most of the attributes are just copied from the metadata document. Note that if a certain attribute is missing from the metadata, it will be missing from the attribute set as well.

Attribute	Type	Comment
abstract	String
crs	Integer	The EPSG id of the coordinate reference system. If not known, the attribute will not be set.
extentEast	Double	The eastern longitude of the bounding box of the map.
extentNorth	Double	The northern latitude of the bounding box of the map.
extentSouth	Double	The southern latitude of the bounding box of the map.
extentWest	Double	The western longitude of the bounding box of the map.
isLocal	Bool	True if the map is a local map; False if the map is a remote OGC WMS map.
keywords	String	A comma-separated list of all keywords from the metadata. Note that all keywords will be listed twice; once with no prefix and once prefixed with a thesaurus name. See CatalogMetadata.Keywords.
language	String
latestDataRevisionDate	String
latestRevisionDate	String
name	String
ogcServiceType	String	"None", "WMS", "WMTS", "WCS" or "WFS"
resourceIdentifier	String
title	String
topics	String	A comma-separated list of all topics from the metadata.
verticalCrs	Integer	The EPSG id of the vertical coordinate reference system. If not known, the attribute will not be set.
zIndex	Integer

When this class is used with a CatalogLoadLayerSet, some additional properties can be used to modify the loaded maps in various ways. For instance, it is possible to override some metadata properties like display names and descriptions, or to load the maps but disable them before adding them to the CatalogLoadLayerSet.

If used by an application as argument to Catalog.GetMaps or Catalog.GetDataSets, only the query string is used.

Example

// Shows how to find maps that match a CatalogQuery
public static void FindMapsMatchingQueryInCatalog()
{
    // Load the catalog
    Catalog catalog = new Catalog("rootDir");

    // This will find all map metadata records with the name 'WorldMap'
    CatalogQuery q1 = new CatalogQuery("name = \"WorldMap\"");
    CatalogMetadataCollection meta1 = catalog.GetMaps(q1);

    // This will find all map metadata records with the word 'Elevation' or 'Height'
    // in the title, written in English
    CatalogQuery q2 = new CatalogQuery(
		"(like(title, \"*Elevation*\") or like(title, \"*Height*\")) " +
		"and language = \"eng\"");
    CatalogMetadataCollection meta2 = catalog.GetMaps(q2);
    
    // This will return all available map metadata records
    CatalogQuery q3 = new CatalogQuery("true");
    CatalogMetadataCollection meta3 = catalog.GetMaps(q3);
}

Inheritance Hierarchy

System.Object (not available in C#)
  EngineObject
    ResourceObject
      CatalogQuery

Platforms

Windows, Linux, Android

CatalogQuery Members

The CatalogQuery type has the following members.

Constructors

Name	Description
CatalogQuery	Initializes a new instance of the CatalogQuery class with the given query string.

Properties

Name	Description
Description	Gets or sets a string that will replace the Layer.Description property of the loaded maps.
DisplayName	Gets or sets a string that will replace the Layer.DisplayName property of the loaded maps.
Enabled	Gets or sets a flag indicating that the loaded maps should be enabled or disabled after they have been loaded.
EnabledStyles	Gets a list of named styles that should be enabled for the loaded maps.
IsDisposed	Gets a value that tells whether the current CatalogQuery has been disposed. Inherited from EngineObject
MaxScale	Gets or sets a scale value that will replace the Layer.MaxScale property of the loaded maps.
MinScale	Gets or sets a scale value that will replace the Layer.MinScale property of the loaded maps.
Name	Gets or sets the name of the CatalogQuery. Inherited from ResourceObject
NativeHandle	Gets the native Carmenta Engine kernel object the current CatalogQuery represents. Inherited from EngineObject
Opacity	Gets or sets an opacity value that will replace the Layer.Opacity property of the loaded maps.
Query	Gets or sets the query string.
IUserProperties.UserProperties	Gets the AttributeSet that contains the user properties. Inherited from IUserProperties

Methods

Name	Description
Clone	Creates a copy of an object. Inherited from EngineObject
Dispose	Releases the reference to the native Carmenta Engine kernel instance the EngineObject represents. Inherited from EngineObject
Equals	Determines whether this instance is equal to another. Inherited from EngineObject

CatalogQuery Class

A class used to query a Catalog for available maps and data sets.

Syntax

C++

class CatalogQuery : public ResourceObject

C++ Smart Pointer Declaration

typedef Ptr<CatalogQuery> CatalogQueryPtr;

Remarks

This class is used to specify search parameters when querying for catalog maps and data sets with Catalog::getMaps and Catalog::getDataSets. Each metadata record in the catalog matching this query will be returned.

Query String	Result
true	All services will match the query.
name = "WorldMap"	Services with the name WorldMap will match the query.
language = "eng"	All services with the language English set will match the query.

Attribute	Type	Comment
abstract	String
crs	Integer	The EPSG id of the coordinate reference system. If not known, the attribute will not be set.
extentEast	Double	The eastern longitude of the bounding box of the map.
extentNorth	Double	The northern latitude of the bounding box of the map.
extentSouth	Double	The southern latitude of the bounding box of the map.
extentWest	Double	The western longitude of the bounding box of the map.
isLocal	Bool	True if the map is a local map; False if the map is a remote OGC WMS map.
keywords	String	A comma-separated list of all keywords from the metadata. Note that all keywords will be listed twice; once with no prefix and once prefixed with a thesaurus name. See CatalogMetadata::keywords.
language	String
latestDataRevisionDate	String
latestRevisionDate	String
name	String
ogcServiceType	String	"None", "WMS", "WMTS", "WCS" or "WFS"
resourceIdentifier	String
title	String
topics	String	A comma-separated list of all topics from the metadata.
verticalCrs	Integer	The EPSG id of the vertical coordinate reference system. If not known, the attribute will not be set.
zIndex	Integer

If used by an application as argument to Catalog::getMaps or Catalog::getDataSets, only the query string is used.

Example

C++

// Shows how to find maps that match a CatalogQuery
static void findMapsMatchingQueryInCatalog()
{
	// Load the catalog
	CatalogPtr catalog = new Catalog("rootDir");

	// This will find all map metadata records with the name 'WorldMap'
	CatalogQueryPtr q1 = new CatalogQuery("name = \"WorldMap\"");
	CatalogMetadataCollectionPtr meta1 = catalog->getMaps(q1);

	// This will find all map metadata records with the word 'Elevation' or 'Height'
	// in the title, written in English
	const char* str = 
		"(like(title, \"*Elevation*\") or like(title, \"*Height*\")) "
		"and language = \"eng\"";
	CatalogQueryPtr q2 = new CatalogQuery(str);
	CatalogMetadataCollectionPtr meta2 = catalog->getMaps(q2);

	// This will return all available map metadata records
	CatalogQueryPtr q3 = new CatalogQuery("true");
	CatalogMetadataCollectionPtr meta3 = catalog->getMaps(q3);
}

Inheritance Hierarchy

EngineObject
ResourceObject
CatalogQuery

Platforms

Windows, Linux, Android

CatalogQuery Members

The CatalogQuery type has the following members.

Constructors

Name	Description
CatalogQuery	Initializes a new instance of the CatalogQuery class with the given query string.

Properties

Name	Description
description	Gets or sets a string that will replace the Layer::description property of the loaded maps.
displayName	Gets or sets a string that will replace the Layer::displayName property of the loaded maps.
enabled	Gets or sets a flag indicating that the loaded maps should be enabled or disabled after they have been loaded.
enabledStyles	Gets a list of named styles that should be enabled for the loaded maps.
maxScale	Gets or sets a scale value that will replace the Layer::maxScale property of the loaded maps.
minScale	Gets or sets a scale value that will replace the Layer::minScale property of the loaded maps.
name	Gets or sets the name of the CatalogQuery. Inherited from ResourceObject
opacity	Gets or sets an opacity value that will replace the Layer::opacity property of the loaded maps.
query	Gets or sets the query string.
IUserProperties::userProperties	Gets the AttributeSet that contains the user properties. Inherited from IUserProperties

Methods

Name	Description
clone	Creates a copy of an object. Inherited from EngineObject
equals	Determines whether this instance is equal to another. Inherited from EngineObject

CatalogQuery Class

A class used to query a Catalog for available maps and data sets.

Syntax

Java

public class CatalogQuery extends ResourceObject

Remarks

This class is used to specify search parameters when querying for catalog maps and data sets with Catalog.getMaps and Catalog.getDataSets. Each metadata record in the catalog matching this query will be returned.

Query String	Result
true	All services will match the query.
name = "WorldMap"	Services with the name WorldMap will match the query.
language = "eng"	All services with the language English set will match the query.

Attribute	Type	Comment
abstract	String
crs	Integer	The EPSG id of the coordinate reference system. If not known, the attribute will not be set.
extentEast	Double	The eastern longitude of the bounding box of the map.
extentNorth	Double	The northern latitude of the bounding box of the map.
extentSouth	Double	The southern latitude of the bounding box of the map.
extentWest	Double	The western longitude of the bounding box of the map.
isLocal	Bool	True if the map is a local map; False if the map is a remote OGC WMS map.
keywords	String	A comma-separated list of all keywords from the metadata. Note that all keywords will be listed twice; once with no prefix and once prefixed with a thesaurus name. See CatalogMetadata.keywords.
language	String
latestDataRevisionDate	String
latestRevisionDate	String
name	String
ogcServiceType	String	"None", "WMS", "WMTS", "WCS" or "WFS"
resourceIdentifier	String
title	String
topics	String	A comma-separated list of all topics from the metadata.
verticalCrs	Integer	The EPSG id of the vertical coordinate reference system. If not known, the attribute will not be set.
zIndex	Integer

If used by an application as argument to Catalog.getMaps or Catalog.getDataSets, only the query string is used.

Example

Java

// Shows how to find maps that match a CatalogQuery
public static void findMapsMatchingQueryInCatalog()
{
    // Load the catalog
    Catalog catalog = new Catalog("rootDir");

    // This will find all map metadata records with the name 'WorldMap'
    CatalogQuery q1 = new CatalogQuery("name = \"WorldMap\"");
    CatalogMetadataCollection meta1 = catalog.getMaps(q1);

    // This will find all map metadata records with the word 'Elevation' or 'Height'
    // in the title, written in English
    CatalogQuery q2 = new CatalogQuery(
		"(like(title, \"*Elevation*\") or like(title, \"*Height*\")) " + 
		"and language = \"eng\"");
    CatalogMetadataCollection meta2 = catalog.getMaps(q2);
    
    // This will return all available map metadata records
    CatalogQuery q3 = new CatalogQuery("true");
    CatalogMetadataCollection meta3 = catalog.getMaps(q3);
}

Inheritance Hierarchy

System::Object (not available in Java)
  EngineObject
    ResourceObject
      CatalogQuery

Platforms

Windows, Linux, Android

CatalogQuery Members

The CatalogQuery type has the following members.

Constructors

Name	Description
CatalogQuery	Initializes a new instance of the CatalogQuery class with the given query string.

Properties

Name	Description
description	Gets or sets a string that will replace the Layer.description property of the loaded maps.
displayName	Gets or sets a string that will replace the Layer.displayName property of the loaded maps.
enabled	Gets or sets a flag indicating that the loaded maps should be enabled or disabled after they have been loaded.
enabledStyles	Gets a list of named styles that should be enabled for the loaded maps.
isDisposed	Gets a value that tells whether the current CatalogQuery has been disposed. Inherited from EngineObject
maxScale	Gets or sets a scale value that will replace the Layer.maxScale property of the loaded maps.
minScale	Gets or sets a scale value that will replace the Layer.minScale property of the loaded maps.
name	Gets or sets the name of the CatalogQuery. Inherited from ResourceObject
opacity	Gets or sets an opacity value that will replace the Layer.opacity property of the loaded maps.
query	Gets or sets the query string.
IUserProperties.userProperties	Gets the AttributeSet that contains the user properties. Inherited from IUserProperties

Methods

Name	Description
clone	Creates a copy of an object. Inherited from EngineObject
dispose	Releases the reference to the native Carmenta Engine kernel instance the EngineObject represents. Inherited from EngineObject
equals	Determines whether this instance is equal to another. Inherited from EngineObject

CatalogQuery Class

A class used to query a Catalog for available maps and data sets.

Syntax

Python

class CatalogQuery ( ResourceObject )

Remarks

Query String	Result
true	All services will match the query.
name = "WorldMap"	Services with the name WorldMap will match the query.
language = "eng"	All services with the language English set will match the query.

Attribute	Type	Comment
abstract	String
crs	Integer	The EPSG id of the coordinate reference system. If not known, the attribute will not be set.
extentEast	Double	The eastern longitude of the bounding box of the map.
extentNorth	Double	The northern latitude of the bounding box of the map.
extentSouth	Double	The southern latitude of the bounding box of the map.
extentWest	Double	The western longitude of the bounding box of the map.
isLocal	Bool	True if the map is a local map; False if the map is a remote OGC WMS map.
keywords	String	A comma-separated list of all keywords from the metadata. Note that all keywords will be listed twice; once with no prefix and once prefixed with a thesaurus name. See CatalogMetadata.keywords.
language	String
latestDataRevisionDate	String
latestRevisionDate	String
name	String
ogcServiceType	String	"None", "WMS", "WMTS", "WCS" or "WFS"
resourceIdentifier	String
title	String
topics	String	A comma-separated list of all topics from the metadata.
verticalCrs	Integer	The EPSG id of the vertical coordinate reference system. If not known, the attribute will not be set.
zIndex	Integer

If used by an application as argument to Catalog.getMaps or Catalog.getDataSets, only the query string is used.

Example

Python

def Example():

    # Load the catalog
    catalog = Catalog("rootDir")

    # This will find all map metadata records with the name 'WorldMap'
    q1 = CatalogQuery("name = \"WorldMap\"")
    meta1 = catalog.getMaps(q1)

    # This will find all map metadata records with the word 'Elevation' or 'Height'
    # in the title, written in English
    q2 = CatalogQuery("(like(title, \"*Elevation*\") or like(title, \"*Height*\")) and language = \"eng\"")
    meta2 = catalog.getMaps(q2)
    
    # This will return all available map metadata records
    q3 = new CatalogQuery("true")
    meta3 = catalog.getMaps(q3)

Inheritance Hierarchy

EngineObject
ResourceObject
CatalogQuery

Platforms

Windows, Linux, Android

CatalogQuery Members

The CatalogQuery type has the following members.

Constructors

Name	Description
CatalogQuery	Initializes a new instance of the CatalogQuery class with the given query string.

Properties

Name	Description
description	Gets or sets a string that will replace the Layer.description property of the loaded maps.
displayName	Gets or sets a string that will replace the Layer.displayName property of the loaded maps.
enabled	Gets or sets a flag indicating that the loaded maps should be enabled or disabled after they have been loaded.
enabledStyles	Gets a list of named styles that should be enabled for the loaded maps.
maxScale	Gets or sets a scale value that will replace the Layer.maxScale property of the loaded maps.
minScale	Gets or sets a scale value that will replace the Layer.minScale property of the loaded maps.
name	Gets or sets the name of the CatalogQuery. Inherited from ResourceObject
opacity	Gets or sets an opacity value that will replace the Layer.opacity property of the loaded maps.
query	Gets or sets the query string.
IUserProperties.userProperties	Gets the AttributeSet that contains the user properties. Inherited from IUserProperties

Methods

Name	Description
clone	Creates a copy of an object. Inherited from EngineObject
equals	Determines whether this instance is equal to another. Inherited from EngineObject

CatalogQuery Class

In this article

Syntax

Remarks

Example

Inheritance Hierarchy

Platforms

See Also

Reference

CatalogQuery Members

CatalogQuery Class

In this article

Syntax

Remarks

Example

Inheritance Hierarchy

Platforms

See Also

Reference

CatalogQuery Members

CatalogQuery Class

In this article

Syntax

Remarks

Example

Inheritance Hierarchy

Platforms

See Also

Reference

CatalogQuery Members

CatalogQuery Class

In this article

Syntax

Remarks

Example

Inheritance Hierarchy

Platforms

See Also

Reference

CatalogQuery Members