Class Citations
Citation constants:
 - Instances of Citationare references mostly for human reading.
- Instances of IdentifierSpaceprovide the code spaces for identifiers (most often Coordinate Reference System identifiers) together with information about who maintains those identifiers.
"EPSG:4326" is a widely-used identifier
 for the “World Geodetic System (WGS) 1984” Coordinate Reference System (CRS).
 The "4326" part is the identifier code and
 the "EPSG" part is the identifier code space.
 The meaning of codes in that code space is controlled by an authority,
 the “EPSG Geodetic Parameter Dataset”. The cited
 responsible party for the EPSG dataset is the “International Association of Oil & Gas producers” (IOGP).
 - DefaultCitation.getIdentifiers()for the- ISBNand- ISSNconstants.
- ImmutableIdentifier.getAuthority()for other- IdentifierSpaceconstants.
- DefaultMetadata.getMetadataStandards()for other- Citationconstants.
- Inferring an identifier from a citation (this is useful mostly with IdentifierSpaceinstances).
- Determining if two instances can be considered the same Citationby comparing their titles or their identifiers.
- Since:
- 0.3
Defined in the sis-metadata module
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Field SummaryFieldsModifier and TypeFieldDescriptionstatic final IdentifierSpace<Integer>The authority for identifiers of objects defined by the EPSG Geodetic Parameter Dataset.static final IdentifierSpace<String>The authority for identifiers of objects defined by ESRI.static final IdentifierSpace<Integer>The authority for identifiers of objects defined by the the GeoTIFF specification.static final IdentifierSpace<String>The International Standard Book Number (ISBN) defined by ISO-2108.The Geographic Information — Metadata standards defined by ISO 19115.static final IdentifierSpace<String>The International Standard Serial Number (ISSN) defined by ISO-3297.static final IdentifierSpace<Integer>The authority for identifiers of objects defined by MapInfo.static final IdentifierSpace<String>The authority for identifiers of objects defined by the netCDF specification.static final IdentifierSpace<String>The authority for identifiers found in specifications from the Open Geospatial Consortium.static final IdentifierSpace<String>The authority for identifiers of objects defined by the PROJ project.static final IdentifierSpace<Integer>The IHO transfer standard for digital hydrographic data specification.static final CitationThe codespace of objects that are specific to the Apache SIS project.static final IdentifierSpace<String>The authority for identifiers of objects defined by the World Meteorological Organization.static final IdentifierSpace<Integer>The authority for identifiers of objects defined by the Web Map Service (WMS) specification.
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Method SummaryModifier and TypeMethodDescriptionstatic CitationReturns a citation of the given identifier.static StringgetIdentifier(Citation citation) Infers an identifier from the given citation, or returnsnullif no identifier has been found.static booleanidentifierMatches(Citation citation, String identifier) Returnstrueif at least one identifier in the given citation have a code matching the given string.static booleanidentifierMatches(Citation c1, Citation c2) static booleantitleMatches(Citation citation, String title) static booleantitleMatches(Citation c1, Citation c2) Returnstrueif at least one title or alternate title inc1is leniently equal to a title or alternate title inc2.static StringtoCodeSpace(Citation citation) Infers a code space from the given citation, or returnsnullif none.static Citation[]values()Returns the values declared in thisCitationsclass.
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Field Details- 
ISO_19115The Geographic Information — Metadata standards defined by ISO 19115. This list contains two standards published by the International Organization for Standardization:- ISO 19115-1 Geographic Information — Metadata Part 1: Fundamentals
- ISO 19115-2 Geographic Information — Metadata Part 2: Extensions for imagery and gridded data
 MI_BandandMD_Band). This is why those standards are defined in a collection rather than as separated constants.Content and future evolutionThe content of this list may vary in future Apache SIS versions depending on the evolution of standards and in the way that SIS support them. The current content is:- ISO 19115-1:2014 at index 0.
- ISO 19115-2:2019 at index 1.
 Main usageThis value can be returned by:- Since:
- 0.6
 
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EPSGThe authority for identifiers of objects defined by the EPSG Geodetic Parameter Dataset. EPSG is not an organization by itself, but is the identifier space managed by the International Association of Oil & Gas producers (IOGP) organization for Coordinate Reference System identifiers. EPSG is the default namespace of map projection method and parameter names in Apache SIS.Historical note: The EPSG acronym meaning was “European Petroleum Survey Group”. But this meaning does not apply anymore since the European and American associations merged into the “Association of Oil & Gas producers” (OGP), later renamed as IOGP. The legacy acronym now applies only to the database Coordinate Reference System definitions, known as “EPSG Geodetic Parameter Dataset”.The citation responsible party is the IOGP organization, but the namespace is"EPSG".When to use "EPSG" and "IOGP"For all usages except GML, the"EPSG"namespace shall be used for identifying Coordinate Reference System objects. But in the particular case of GML, both"EPSG"and"IOGP"appear in different locations. For example:
 Guidelines:<gml:identifier codeSpace="IOGP">urn:ogc:def:crs:EPSG::4326</gml:identifier> - The "EPSG"name shall be used in URN. This part of the URN is called "the authority" and is returned by bothIdentifier.getAuthority()andIdentifier.getCodeSpace().
- The "IOGP"name appears in the GMLcodeSpaceattribute, but despite the attribute name this is not theIdentifier.getCodeSpace()value of the"EPSG:4326"identifier. Instead, Apache SIS considers"IOGP"as the codespace of the"IOGP:EPSG"identifier, which is the identifier of this citation.
 "IOGP:EPSG"identifier is handled in a special way bygetIdentifier(Citation), which return only"EPSG".Main usageThis value can be returned by:- ImmutableIdentifier.getAuthority()
- ConcurrentAuthorityFactory.getAuthority()with the addition of version information.
 - Since:
- 0.4
 
- The 
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WMSThe authority for identifiers of objects defined by the Web Map Service (WMS) specification. The WMS 1.3 specifications is also known as ISO 19128 Geographic Information — Web map server interface standard.The citation responsible parties are the OGC and ISO organizations. The namespace declared by this constant is "OGC", but the"CRS","AUTO"and"AUTO2"namespaces are also commonly found in practice.Main usageThis value can be returned by:- Since:
- 0.7
 
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OGCThe authority for identifiers found in specifications from the Open Geospatial Consortium. The name of this identifier space is fixed to"OGC". Apache SIS uses this authority mostly for map projection methods and parameters as they were defined in older OGC specifications (in more recent specifications, EPSG identifiers tend to be more widely used).Example the Mercator projection can be defined by an operation method having the"OGC:Mercator_1SP"identifier and the following parameters:Example of identifiers in OGC name space Name in OGC namespace Name in default namespace (EPSG) "OGC:semi_major""OGC:semi_minor""OGC:latitude_of_origin"Latitude of natural origin "OGC:central_meridian"Longitude of natural origin "OGC:scale_factor"Scale factor at natural origin "OGC:false_easting"False easting "OGC:false_northing"False northing Specifications referencedThe specification actually referenced by this citation is implementation dependent and may change in future SIS version. Some of the specifications used are: We do not commit to a particular OGC specification in order to keep the flexibility to change the title or URL according newer OGC publications.Main usageThis value can be returned by:
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ESRIThe authority for identifiers of objects defined by ESRI. The name of this identifier space is fixed to"ESRI". This citation is used as the authority for many map projection method and parameter names other than the EPSG ones.Note many parameter names defined by OGC are very similar to the ESRI ones, except for the case. Examples:Example of identifiers in ESRI name space Name in ESRI namespace Name in OGC namespace "ESRI:Semi_Major""OGC:semi_major""ESRI:Semi_Minor""OGC:semi_minor""ESRI:Latitude_Of_Origin""OGC:latitude_of_origin""ESRI:Central_Meridian""OGC:central_meridian""ESRI:Scale_Factor""OGC:scale_factor""ESRI:False_Easting""OGC:false_easting""ESRI:False_Northing""OGC:false_northing"Main usageThis value can be returned by:
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WMOThe authority for identifiers of objects defined by the World Meteorological Organization. The name of this identifier space is fixed to"WMO". This citation is used as the authority for some coordinate operations other than EPSG and ESRI ones, for example "Rotated latitude/longitude".- Since:
- 1.2
 
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NETCDFThe authority for identifiers of objects defined by the netCDF specification. The name of this identifier space is fixed to"NetCDF". This citation is used as the authority for some map projection method and parameter names as used in netCDF files.Example the Mercator projection can be defined in a netCDF file with the following parameters:Example of identifiers in netCDF name space Name in netCDF namespace Name in default namespace (EPSG) "NetCDF:semi_major_axis""NetCDF:semi_minor_axis""NetCDF:latitude_of_projection_origin"Latitude of natural origin "NetCDF:longitude_of_projection_origin"Longitude of natural origin "NetCDF:scale_factor_at_projection_origin"Scale factor at natural origin "NetCDF:false_easting"False easting "NetCDF:false_northing"False northing Main usageThis value can be returned by:- Since:
- 0.4
 
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GEOTIFFThe authority for identifiers of objects defined by the the GeoTIFF specification. This specification identifies some map projections by their own numerical codes.Main usageThis value can be returned by:- Since:
- 0.4
 
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PROJ4The authority for identifiers of objects defined by the PROJ project. We use thePROJ4name for historical reasons, because those identifiers were defined mostly when the project was known as "Proj.4". Starting at PROJ version 6, EPSG identifiers should be used instead.Main usageThis value can be returned by:- Since:
- 0.4
 
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MAP_INFOThe authority for identifiers of objects defined by MapInfo.Main usageThis value can be returned by:- Since:
- 0.6
 
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S57The IHO transfer standard for digital hydrographic data specification.Main usageThis value can be returned by:- Since:
- 0.6
 
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ISBNThe International Standard Book Number (ISBN) defined by ISO-2108. The ISO 19115 metadata standard defines a specific attribute for this information, but the SIS library handles it like any other identifier.Main usageThis value can be returned by:- See Also:
 
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ISSNThe International Standard Serial Number (ISSN) defined by ISO-3297. The ISO 19115 metadata standard defines a specific attribute for this information, but the SIS library handles it like any other identifier.Main usageThis value can be returned by:- See Also:
 
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SISThe codespace of objects that are specific to the Apache SIS project.Main usageThis value can be returned by:- Since:
- 0.4
 
 
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Method Details- 
valuesReturns the values declared in thisCitationsclass.- Returns:
- the value declared in this Citationsclass.
- Since:
- 1.0
 
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fromNameReturns a citation of the given identifier. The method makes the following choice:- If the given title is nullor empty (ignoring spaces), then this method returnsnull.
- Otherwise if the given string matches an identifier of one of
       the predefined constants (EPSG,GEOTIFF, etc.), then that constant is returned.
- Otherwise, a new citation is created with the specified name as the title.
 - Parameters:
- identifier- the citation title (or alternate title), or- null.
- Returns:
- a citation using the specified name, or nullif the given title is null or empty.
 
- If the given title is 
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titleMatchesReturnstrueif at least one title or alternate title inc1is leniently equal to a title or alternate title inc2. The comparison is case-insensitive and ignores every character which is not a letter or a digit. The titles ordering is not significant.- Parameters:
- c1- the first citation to compare, or- null.
- c2- the second citation to compare, or- null.
- Returns:
- trueif both arguments are non-null, and at least one title or alternate title matches.
 
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titleMatchesReturnstrueif the title or any alternate title in the given citation matches the given string. The comparison is case-insensitive and ignores every character which is not a letter or a digit.- Parameters:
- citation- the citation to check for, or- null.
- title- the title or alternate title to compare, or- null.
- Returns:
- trueif both arguments are non-null, and the title or an alternate title matches the given string.
 
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identifierMatchesReturnstrueif at least one identifier code inc1is equal to an identifier code inc2. Code spaces are compared only if provided in the two identifiers being compared. Comparisons are case-insensitive and ignores every character which is not a letter or a digit. The identifier ordering is not significant.If (and only if) the citations do not contains any identifier, then this method fallback on titles comparison using the titleMatchesmethod. This fallback exists for compatibility with client codes using the citation titles without identifiers.- Parameters:
- c1- the first citation to compare, or- null.
- c2- the second citation to compare, or- null.
- Returns:
- trueif both arguments are non-null, and at least one identifier matches.
 
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identifierMatchesReturnstrueif at least one identifier in the given citation have a code matching the given string. The comparison is case-insensitive and ignores every character which is not a letter or a digit.If (and only if) the citation does not contain any identifier, then this method fallback on titles comparison using the titleMatchesmethod. This fallback exists for compatibility with citations using title and alternate titles (often abbreviations) without identifiers.- Parameters:
- citation- the citation to check for, or- null.
- identifier- the identifier to compare, or- null.
- Returns:
- trueif both arguments are non-null, and an identifier matches the given string.
 
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getIdentifierInfers an identifier from the given citation, or returnsnullif no identifier has been found. This method is useful for extracting a short designation of an authority (e.g."EPSG") for display purpose. This method performs the following choices:- If the given citation is null, then this method returnsnull.
- Otherwise if the collection of citation identifiers
       contains at least one non-deprecated
       identifier, then:
     - If the codespace (if any) and the code of at least one non-deprecated identifier
           are valid Unicode identifiers
           (with relaxed rules regarding the code), then the first of those identifiers
           is returned in a "[codespace:]code"format. If a codespace exists, then the above restriction about the code is relaxed in two ways:
- Otherwise the first non-empty and non-deprecated identifier is returned in a
           "[codespace:]code"format, despite not being a valid Unicode identifier.
 
- If the codespace (if any) and the code of at least one non-deprecated identifier
           are valid Unicode identifiers
           (with relaxed rules regarding the code), then the first of those identifiers
           is returned in a 
- Otherwise if the citation contains at least one non-deprecated title
       or alternate title, then:
     - If at least one non-deprecated title is a unicode identifier, then the first of those titles is returned.
- Otherwise the first non-empty and non-deprecated title is returned, despite not being a valid Unicode identifier.
 
- Otherwise this method returns null.
 Note: This method searches in alternate titles as a fallback because ISO specification said that those titles are often used for abbreviations. However, titles are never searched if the given citation contains at least one non-empty and non-deprecated identifier.This method ignores leading and trailing whitespaces in every character sequences. Null or empty trimmed character sequences are ignored. This method does not remove ignorable characters. The result is a string which is likely, but not guaranteed, to be a valid XML or Unicode identifier. The returned string is useful when an "identifier-like" string is desired for display or information purpose, but does not need to be a strictly valid identifier.- Parameters:
- citation- the citation for which to get the identifier, or- null.
- Returns:
- a non-empty identifier for the given citation without leading or trailing whitespaces,
         or nullif the given citation is null or does not declare any identifier or title.
 
- If the given citation is 
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toCodeSpaceInfers a code space from the given citation, or returnsnullif none. This method is useful for extracting a short designation of an authority (e.g."EPSG") for processing purpose. This method performs the following actions:- If the given citation is an instance of IdentifierSpace, returnsIdentifierSpace.getName().
- Otherwise, performs the same work than getIdentifier(Citation)except that'_'is used instead of':'as the separator between the codespace and the code.
- If the result of above method call is nullor is not a valid Unicode identifier, then returnnull.
- Otherwise remove the ignorable characters, if any, and returns the result.
 Note: examples of ignorable identifier characters are zero width space or word joiner. Those characters are illegal in XML identifiers, and should therfore be removed if the Unicode identifier may also be used as XML identifier.If non-null, the result is suitable for use as a XML identifier except for a few uncommon characters.Note: the following characters are invalid in XML identifiers. However, since they are valid in Unicode identifiers, they could be included in the string returned by this method:- µ
- ª(feminine ordinal indicator)
- º(masculine ordinal indicator)
- ⁔
 - Parameters:
- citation- the citation for which to infer the code space, or- null.
- Returns:
- a non-empty code space for the given citation without leading or trailing whitespaces,
         or nullif the given citation is null or does not have any Unicode identifier or title.
- Since:
- 1.0
 
- If the given citation is an instance of 
 
-