org.opengis.metadata.package-info Maven / Gradle / Ivy
/*
* GeoTools - The Open Source Java GIS Toolkit
* http://geotools.org
*
* (C) 2011, Open Source Geospatial Foundation (OSGeo)
* (C) 2004-2005, Open Geospatial Consortium Inc.
*
* All Rights Reserved. http://www.opengis.org/legal/
*/
/**
* Root package for {@linkplain org.opengis.metadata.MetaData metadata}. The following is adapted
* from OpenGIS® Metadata (Topic 11)
* specification.
*
* The notion of cataloguing a set of related documents together in a
* discoverable series is common in map catalogues. With digital spatial data, the definition of
* what constitutes a "dataset" is more problematic and reflects the institutional and software
* environments of the originating organization. Common metadata can be derived for a series of
* related spatial datasets, and such metadata is generally relevant or can be inherited by each of
* the dataset instances. Software to support this inheritance of metadata for geographic data
* within a cataloguing system can simplify data entry, update and reporting.
*
*
There is a potential hierarchy of re-usable metadata that can be employed in
* implementing a metadata collection. By creating several levels of abstraction, a linked hierarchy
* can assist in filtering or targeting user queries to the requested level of detail. The hierarchy
* should not necessarily be interpreted to require multiple copies of metadata being managed
* on-line. Conversely, the definition of general metadata can be supplemented by spatially specific
* metadata that, when queried, either inherits or overrides the general case. Through use of
* pointers this method can reduce the redundancy of metadata managed at a site and provide for
* different views of the holdings by users.
*
*
Data series metadata
*
* A series or collection of spatial data which share similar characteristics of
* theme, source date, resolution, and methodology. The exact definition of what constitutes a
* series entry will be determined by the data provider. Examples of data series metadata entries
* may include:
*
*
* -
*
A flight line of digital aerial photographs collected during a single
* flight with one camera and film type. A continuous scan swathe collected from a satellite
* using the same sensors on a single orbital pass.
*
-
*
A collection of raster map data captured from a common series of paper
* maps.
*
-
*
A collection of vector datasets depicting surface hydrography with
* associated attribution for multiple administrative areas within a country.
*
*
* The creation of a "data series" metadata level is an optional feature that
* allows users to consult higher-level characteristics for data search. The definition of this type
* of metadata may be adequate for the initial characterization of available spatial data, but may
* not be adequate for detailed assessment of data quality of specific datasets.
*
*
Dataset metadata
*
* For the purposes of this specification, a dataset should be a consistent
* spatial data product instance that can be generated or made available by a spatial data
* distributor. A dataset may be a member of a data series, as defined in the previous subclause. A
* dataset may be composed of a set of identified feature types and instances, and attribute types
* and instances as described in the following four subclauses.
*
*
On a demand basis, metadata from series and dataset information will be merged
* to present the user with a view of the metadata at the dataset level of abstraction. Metadata for
* which no hierarchy is listed are interpreted to be "dataset" metadata, by default.
*
*
Feature type metadata
*
* Spatial constructs known as features are grouped spatial primitives (0-, 1-
* and 2-dimensional geometric objects) that have a common identity. Spatial data services may elect
* to support feature type-level metadata where it is available and make such metadata available for
* query or retrieval. Feature Type -level metadata, together with feature instance-, attribute
* type- and attribute instance-level metadata, will be grouped into datasets, as defined in the
* previous subclause. Examples of feature type metadata entries may include:
*
*
* - All bridges within a dataset.
*
*
* Feature instance metadata
*
* Feature instances are spatial constructs (features) that have a direct
* correspondence with a real world object. Spatial data services may elect to support feature
* instance-level metadata where it is available and make such metadata available for query or
* retrieval. Feature Instance-level metadata, together with feature type-, attribute type- and
* attribute instance-level metadata, will be grouped into datasets. Examples of feature instance
* metadata entries may include:
*
*
* - The Sydney harbour bridge.
*
- The Golden Gate bridge, in San Francisco.
*
*
* Attribute type metadata
*
* Attribute types are the digital parameters that describe a common aspect of
* grouped spatial primitives (0-, 1- and 2- dimensional geometric objects). Spatial data services
* may elect to support attribute type-level metadata where it is available and make such metadata
* available for query or retrieval. Attribute type-level metadata, together with feature type-,
* feature instance and attribute instance-level metadata, will be grouped into datasets. Examples
* of attribute type metadata entries may include:
*
*
* - Overhead clearance associated with a bridge.
*
*
* Attribute instance metadata
*
* Attribute instances are the digital parameters that describe an aspect of a
* feature instance. Spatial data services may elect to support attribute instance-level metadata
* where it is available and make such metadata available for query or retrieval. Attribute
* instance-level metadata, together with feature type-, feature instance and attribute typelevel
* metadata, will be grouped into datasets. Examples of attribute instance metadata entries may
* include:
*
*
* - The overhead clearance associated with a specific bridge across a road.
*
*
* @version ISO 19115
* @since GeoAPI 2.0
*/
package org.opengis.metadata;