Package org.geotools.api.feature

Interface Attribute

All Superinterfaces:
Property
All Known Subinterfaces:
ComplexAttribute, Feature, GeometryAttribute, SimpleFeature
All Known Implementing Classes:
AttributeImpl, ComplexAttributeImpl, DecoratingFeature, FeatureImpl, GeometryAttributeImpl, JDBCFeatureReader.ResultSetFeature, MongoDBObjectFeature, MongoFeature, PreGeneralizedSimpleFeature, ReadonlyAttributeDecorator, SimpleFeatureImpl
public interface Attribute extends Property
An extension of Property for an attribute, or data.

The notion of an "attribute" is similar to that of an attribute in UML.

This interface is capable of modelling "primitive data", things like strings, numerics, dates, etc... However for "complex data" (that is non-primitive data types which are made up other primitive data types), a specific sub-interface is used, see ComplexAttribute.

An analogy for an attribute is a "field" in a java object. A field also brings together a field name, value and type.

Identifiable

When an attribute is identifiable the getIdentifier() method returns a unique identifier for the attribute. The type of the attribute is used to determine identifiability. 
 Attribute attribute = ...;
 if ( attribute.getType().isIdentified() ) {
   String id = attribute.getID();
 }

Validation

An attribute may hold any value at runtime; checking that the value meets the constraints supplied by the AttributeType is the work of the validate() method.
Author:
Jody Garnett (Refractions Research), Justin Deoliveira (The Open Planning Project)
See Also:

  • Method Details

    • getDescriptor

      AttributeDescriptor getDescriptor()
      Override of Property.getDescriptor() which type narrows to AttributeDescriptor.
      Specified by:
      getDescriptor in interface Property
      Returns:
      The attribute descriptor, may be null if this is a top level type
      See Also:

    • getType

      AttributeType getType()
      Override of Property.getType() which type narrows to AttributeType.
      Specified by:
      getType in interface Property
      Returns:
      The attribute type.
      See Also:

    • getIdentifier

      Identifier getIdentifier()
      Unique Identifier for the attribute.

      This value is non-null in the case that getType().isIdentifiable() is true.

      Returns:
      A unique identifier for the attribute, or null if the attribute is non-identifiable.

    • validate

      void validate() throws IllegalAttributeException
      Check the attribute value against the constraints provided by the AttributeDescriptor.

      Please note this method checks the value only - it should have the correct java binding, it should only be null if isNillable is true; and if a value is provided it should satisfy all of the restrictions provided.

      To check the the number of times an attribute is used (minOccurs and maxOccurs) please use ComplexAttribute.validate().

      Throws:
      IllegalAttributeException