Package org.odpi.openmetadata.frameworks.integration.dcat.mapping

Class DcatMappingBase

java.lang.Object

org.odpi.openmetadata.frameworks.integration.dcat.mapping.DcatMappingBase

Direct Known Subclasses:

DcatGenerator, DcatMapper

public abstract class DcatMappingBase
extends Object

DcatMappingBase holds the names and helper methods shared by the mapper, which catalogs DCAT documents in open metadata, and the generator, which creates DCAT documents from open metadata.

The mapping between the two is as follows. A dcat:Dataset is a DataSet asset and each of its dcat:Distributions is a DataFile asset (when it has a download URL) or a DataStore asset (when it only has an access URL) that is anchored to the data set and linked to it with a DataSetContent relationship. A dcat:DatasetSeries is a DataSet asset linked to its member data sets by DataSetContent relationships. A dcat:DataService is a DeployedAPI asset with an Endpoint for each endpoint URL, linked to the data sets it serves by DataSetContent relationships. A dcat:Catalog is a CollectionFolder whose members are its datasets, data services and nested catalogs. Keywords are SearchKeywords, the publisher is an Organization that scopes the element, contact points are ContactDetails, the licence is a LicenseType and the standards and documentation pages are ExternalReferences. The DCAT properties that have no equivalent in open metadata are kept in the additional properties with names that begin "dcat.".

Field Summary

Fields

Modifier and Type	Field	Description
static final String	ACCESS_RIGHTS
static final String	ACCESS_SERVICES_JSON
static final String	ACCESS_URL
static final String	ACCRUAL_PERIODICITY
static final String	ADDITIONAL_PROPERTY_PREFIX	Prefix of the additional properties that hold values from a DCAT description.
static final String	BYTE_SIZE
static final String	CATALOG_KIND
static final String	CATALOG_QUALIFIED_NAME_PREFIX	Prefix of the qualified name of a collection catalogued from a dcat:Catalog.
static final String	CHECKSUM_ALGORITHM
static final String	CHECKSUM_VALUE
static final String	COMPRESS_FORMAT
static final String	CONFORMS_TO_JSON
static final String	CONFORMS_TO_LABEL	Label on the ExternalReferenceLink relationship to a standard that the resource conforms to.
static final String	CONTACT_POINT_JSON
protected final ConnectorContextBase	context
static final String	CREATORS_JSON
static final String	DATA_SERVICE_KIND
static final String	DATA_SERVICE_QUALIFIED_NAME_PREFIX	Prefix of the qualified name of a deployed API catalogued from a dcat:DataService.
static final String	DATASET_KIND
static final String	DATASET_QUALIFIED_NAME_PREFIX	Prefix of the qualified name of a data set catalogued from a dcat:Dataset or dcat:DatasetSeries.
static final String	DATASET_SERIES_KIND
static final String	DESCRIPTION_TRANSLATIONS_JSON
static final String	DISTRIBUTION_KIND
static final String	DISTRIBUTION_QUALIFIED_NAME_PREFIX	Prefix of the qualified name of an asset catalogued from a dcat:Distribution.
static final String	DOCUMENTATION_LABEL	Label on the ExternalReferenceLink relationship to a page that documents the resource.
static final String	DOWNLOAD_URL
static final String	ENDPOINT_DESCRIPTIONS_JSON
static final String	FORMAT
static final String	GENERATED_IRI_PREFIX	Prefix of the IRI generated for an open metadata element that was not catalogued from a DCAT description.
static final String	HOMEPAGE
static final String	IDENTIFIERS_JSON
static final String	IRI
static final String	ISSUED
static final String	KIND
static final String	LANGUAGES_JSON
static final String	LICENSE_JSON
static final String	MEDIA_TYPE
static final String	MODIFIED
static final String	OTHER_PROPERTIES_JSON
static final String	PACKAGE_FORMAT
static final String	PREVIOUS_VERSION
protected final PropertyHelper	propertyHelper
static final String	PUBLISHER_JSON
static final String	RESOURCE_TYPE
static final String	RIGHTS
static final String	SEPARATOR	Separator used in qualified names.
static final String	SPATIAL_JSON
static final String	SPATIAL_RESOLUTION_IN_METERS
static final String	STATUS
static final String	TEMPORAL_JSON
static final String	TEMPORAL_RESOLUTION
static final String	THEME_TAXONOMIES_JSON
static final String	THEMES_JSON
static final String	TITLE_TRANSLATIONS_JSON
static final String	VERSION_NOTES

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	DcatMappingBase(ConnectorContextBase context)	Constructor

Method Summary

Modifier and Type	Method	Description
protected OpenMetadataElement	findElement(String qualifiedName)	Return the element with the requested qualified name.
protected String	findElementGUID(String qualifiedName)	Return the unique identifier of the element with the requested qualified name.
protected Map<String,String>	getAdditionalProperties(OpenMetadataElement element)	Return the additional properties of an element.
protected static <T> T	getBean(Map<String,String> additionalProperties, String name, Class<T> beanClass)	Read a bean from a JSON additional property.
protected static <T> List<T>	getBeanList(Map<String,String> additionalProperties, String name, Class<T> beanClass)	Read a list of beans from a JSON additional property.
protected Set<String>	getLinkedElementGUIDs(String elementGUID, int startingAtEnd, String relationshipTypeName)	Return the unique identifiers of the elements that are linked to an element by a particular type of relationship.
protected List<RelatedMetadataElement>	getRelationships(String elementGUID, int startingAtEnd, String relationshipTypeName)	Return all the relationships of a particular type that are attached to an element.
protected static List<String>	getStringList(Map<String,String> additionalProperties, String name)	Read a list of strings from a JSON additional property.
protected String	getStringProperty(OpenMetadataElement element, String propertyName)	Return a string property of an element.
protected static void	putIfPresent(Map<String,String> additionalProperties, String name, String value)	Add a value to the additional properties if it is not null.
protected static String	toJSON(Object bean)	Convert a bean, list or map to JSON so that it can be kept in the additional properties.

Methods inherited from class java.lang.Object

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

Field Details

ADDITIONAL_PROPERTY_PREFIX

public static final String ADDITIONAL_PROPERTY_PREFIX

Prefix of the additional properties that hold values from a DCAT description.

See Also:

• Constant Field Values

SEPARATOR

public static final String SEPARATOR

Separator used in qualified names.

See Also:

• Constant Field Values

DATASET_QUALIFIED_NAME_PREFIX

public static final String DATASET_QUALIFIED_NAME_PREFIX

Prefix of the qualified name of a data set catalogued from a dcat:Dataset or dcat:DatasetSeries.

See Also:

• Constant Field Values

DISTRIBUTION_QUALIFIED_NAME_PREFIX

public static final String DISTRIBUTION_QUALIFIED_NAME_PREFIX

Prefix of the qualified name of an asset catalogued from a dcat:Distribution.

See Also:

• Constant Field Values

DATA_SERVICE_QUALIFIED_NAME_PREFIX

public static final String DATA_SERVICE_QUALIFIED_NAME_PREFIX

Prefix of the qualified name of a deployed API catalogued from a dcat:DataService.

See Also:

• Constant Field Values

CATALOG_QUALIFIED_NAME_PREFIX

public static final String CATALOG_QUALIFIED_NAME_PREFIX

Prefix of the qualified name of a collection catalogued from a dcat:Catalog.

See Also:

• Constant Field Values

DATASET_KIND

public static final String DATASET_KIND

See Also:

• Constant Field Values

DATASET_SERIES_KIND

public static final String DATASET_SERIES_KIND

See Also:

• Constant Field Values

DISTRIBUTION_KIND

public static final String DISTRIBUTION_KIND

See Also:

• Constant Field Values

DATA_SERVICE_KIND

public static final String DATA_SERVICE_KIND

See Also:

• Constant Field Values

CATALOG_KIND

public static final String CATALOG_KIND

See Also:

• Constant Field Values

KIND

public static final String KIND

See Also:

• Constant Field Values

IRI

public static final String IRI

See Also:

• Constant Field Values

ISSUED

public static final String ISSUED

See Also:

• Constant Field Values

MODIFIED

public static final String MODIFIED

See Also:

• Constant Field Values

RESOURCE_TYPE

public static final String RESOURCE_TYPE

See Also:

• Constant Field Values

RIGHTS

public static final String RIGHTS

See Also:

• Constant Field Values

ACCESS_RIGHTS

public static final String ACCESS_RIGHTS

See Also:

• Constant Field Values

VERSION_NOTES

public static final String VERSION_NOTES

See Also:

• Constant Field Values

STATUS

public static final String STATUS

See Also:

• Constant Field Values

PREVIOUS_VERSION

public static final String PREVIOUS_VERSION

See Also:

• Constant Field Values

IDENTIFIERS_JSON

public static final String IDENTIFIERS_JSON

See Also:

• Constant Field Values

LANGUAGES_JSON

public static final String LANGUAGES_JSON

See Also:

• Constant Field Values

THEMES_JSON

public static final String THEMES_JSON

See Also:

• Constant Field Values

PUBLISHER_JSON

public static final String PUBLISHER_JSON

See Also:

• Constant Field Values

CREATORS_JSON

public static final String CREATORS_JSON

See Also:

• Constant Field Values

LICENSE_JSON

public static final String LICENSE_JSON

See Also:

• Constant Field Values

TITLE_TRANSLATIONS_JSON

public static final String TITLE_TRANSLATIONS_JSON

See Also:

• Constant Field Values

DESCRIPTION_TRANSLATIONS_JSON

public static final String DESCRIPTION_TRANSLATIONS_JSON

See Also:

• Constant Field Values

OTHER_PROPERTIES_JSON

public static final String OTHER_PROPERTIES_JSON

See Also:

• Constant Field Values

ACCRUAL_PERIODICITY

public static final String ACCRUAL_PERIODICITY

See Also:

• Constant Field Values

SPATIAL_JSON

public static final String SPATIAL_JSON

See Also:

• Constant Field Values

TEMPORAL_JSON

public static final String TEMPORAL_JSON

See Also:

• Constant Field Values

SPATIAL_RESOLUTION_IN_METERS

public static final String SPATIAL_RESOLUTION_IN_METERS

See Also:

• Constant Field Values

TEMPORAL_RESOLUTION

public static final String TEMPORAL_RESOLUTION

See Also:

• Constant Field Values

ENDPOINT_DESCRIPTIONS_JSON

public static final String ENDPOINT_DESCRIPTIONS_JSON

See Also:

• Constant Field Values

HOMEPAGE

public static final String HOMEPAGE

See Also:

• Constant Field Values

THEME_TAXONOMIES_JSON

public static final String THEME_TAXONOMIES_JSON

See Also:

• Constant Field Values

ACCESS_URL

public static final String ACCESS_URL

See Also:

• Constant Field Values

DOWNLOAD_URL

public static final String DOWNLOAD_URL

See Also:

• Constant Field Values

MEDIA_TYPE

public static final String MEDIA_TYPE

See Also:

• Constant Field Values

FORMAT

public static final String FORMAT

See Also:

• Constant Field Values

BYTE_SIZE

public static final String BYTE_SIZE

See Also:

• Constant Field Values

COMPRESS_FORMAT

public static final String COMPRESS_FORMAT

See Also:

• Constant Field Values

PACKAGE_FORMAT

public static final String PACKAGE_FORMAT

See Also:

• Constant Field Values

CONFORMS_TO_JSON

public static final String CONFORMS_TO_JSON

See Also:

• Constant Field Values

CHECKSUM_ALGORITHM

public static final String CHECKSUM_ALGORITHM

See Also:

• Constant Field Values

CHECKSUM_VALUE

public static final String CHECKSUM_VALUE

See Also:

• Constant Field Values

ACCESS_SERVICES_JSON

public static final String ACCESS_SERVICES_JSON

See Also:

• Constant Field Values

CONTACT_POINT_JSON

public static final String CONTACT_POINT_JSON

See Also:

• Constant Field Values

CONFORMS_TO_LABEL

public static final String CONFORMS_TO_LABEL

Label on the ExternalReferenceLink relationship to a standard that the resource conforms to.

See Also:

• Constant Field Values

DOCUMENTATION_LABEL

public static final String DOCUMENTATION_LABEL

Label on the ExternalReferenceLink relationship to a page that documents the resource.

See Also:

• Constant Field Values

GENERATED_IRI_PREFIX

public static final String GENERATED_IRI_PREFIX

Prefix of the IRI generated for an open metadata element that was not catalogued from a DCAT description.

See Also:

• Constant Field Values

context

protected final ConnectorContextBase context

propertyHelper

protected final PropertyHelper propertyHelper

Constructor Details

DcatMappingBase

protected DcatMappingBase(ConnectorContextBase context)

Constructor

Parameters:

context - the connector context that provides access to open metadata

Method Details

findElement

protected OpenMetadataElement findElement(String qualifiedName)
                                   throws InvalidParameterException,
PropertyServerException,
UserNotAuthorizedException

Return the element with the requested qualified name.

Parameters:

qualifiedName - unique name

Returns:

element or null if it does not exist

Throws:

InvalidParameterException - one of the parameters is null or invalid.

PropertyServerException - a problem retrieving information from the property server(s).

UserNotAuthorizedException - the requesting user is not authorized to issue this request.

findElementGUID

protected String findElementGUID(String qualifiedName)
                          throws InvalidParameterException,
PropertyServerException,
UserNotAuthorizedException

Return the unique identifier of the element with the requested qualified name.

Parameters:

qualifiedName - unique name

Returns:

unique identifier or null if the element does not exist

Throws:

InvalidParameterException - one of the parameters is null or invalid.

PropertyServerException - a problem retrieving information from the property server(s).

UserNotAuthorizedException - the requesting user is not authorized to issue this request.

getRelationships

protected List<RelatedMetadataElement> getRelationships(String elementGUID,
 int startingAtEnd,
 String relationshipTypeName)
                                                 throws InvalidParameterException,
PropertyServerException,
UserNotAuthorizedException

Return all the relationships of a particular type that are attached to an element.

Parameters:

elementGUID - unique identifier of the starting element

startingAtEnd - which end of the relationship the starting element is at (1 or 2)

relationshipTypeName - type of relationship to follow

Returns:

list of relationships with the element at the other end

Throws:

InvalidParameterException - one of the parameters is null or invalid.

PropertyServerException - a problem retrieving information from the property server(s).

UserNotAuthorizedException - the requesting user is not authorized to issue this request.

getLinkedElementGUIDs

protected Set<String> getLinkedElementGUIDs(String elementGUID,
 int startingAtEnd,
 String relationshipTypeName)
                                     throws InvalidParameterException,
PropertyServerException,
UserNotAuthorizedException

Return the unique identifiers of the elements that are linked to an element by a particular type of relationship.

Parameters:

elementGUID - unique identifier of the starting element

startingAtEnd - which end of the relationship the starting element is at (1 or 2)

relationshipTypeName - type of relationship to follow

Returns:

set of unique identifiers

Throws:

InvalidParameterException - one of the parameters is null or invalid.

PropertyServerException - a problem retrieving information from the property server(s).

UserNotAuthorizedException - the requesting user is not authorized to issue this request.

getStringProperty

protected String getStringProperty(OpenMetadataElement element,
 String propertyName)

Return a string property of an element.

Parameters:

element - element

propertyName - name of the property

Returns:

value or null

getAdditionalProperties

protected Map<String,String> getAdditionalProperties(OpenMetadataElement element)

Return the additional properties of an element.

Parameters:

element - element

Returns:

map - empty if the element has no additional properties

putIfPresent

protected static void putIfPresent(Map<String,String> additionalProperties,
 String name,
 String value)

Add a value to the additional properties if it is not null.

Parameters:

additionalProperties - map to add to

name - name of the property (without the prefix)

value - value (may be null)

toJSON

protected static String toJSON(Object bean)

Convert a bean, list or map to JSON so that it can be kept in the additional properties.

Parameters:

bean - bean, list or map (may be null)

Returns:

JSON string, or null if there is nothing to convert

getStringList

protected static List<String> getStringList(Map<String,String> additionalProperties,
 String name)

Read a list of strings from a JSON additional property.

Parameters:

additionalProperties - additional properties of an element

name - name of the property (without the prefix)

Returns:

list or null

getBeanList

protected static <T> List<T> getBeanList(Map<String,String> additionalProperties,
 String name,
 Class<T> beanClass)

Read a list of beans from a JSON additional property.

Type Parameters:

T - type of bean

Parameters:

additionalProperties - additional properties of an element

name - name of the property (without the prefix)

beanClass - class of the beans

Returns:

list or null

getBean

protected static <T> T getBean(Map<String,String> additionalProperties,
 String name,
 Class<T> beanClass)

Read a bean from a JSON additional property.

Type Parameters:

T - type of bean

Parameters:

additionalProperties - additional properties of an element

name - name of the property (without the prefix)

beanClass - class of the bean

Returns:

bean or null