Package org.geotools.api.feature

Interface ComplexAttribute

All Superinterfaces:
Attribute, Property
All Known Subinterfaces:
Feature, SimpleFeature
All Known Implementing Classes:
ComplexAttributeImpl, DecoratingFeature, FeatureImpl, JDBCFeatureReader.ResultSetFeature, MongoDBObjectFeature, MongoFeature, PreGeneralizedSimpleFeature, SimpleFeatureImpl
public interface ComplexAttribute extends Attribute
An instance of ComplexType which is composed of other properties.

A complex attribute is a container for other properties (attributes + associations). The value of a complex attribute is a collection of those contained properties.

Property Access

The getValue() method returns a collection of the properties contained by the complex attribute. 
    ComplexAttribute attribute = ...;

    //loop through all the properties
    for (Property p : attribute.getValue(); ) {
        // do something with the property
    }

Contained properties can also be fetched by name by Name with the getProperties(Name) and getProperties(String) methods. 
    ComplexAttribute attribute = ...;

    //loop through all the "foo" attributes
    for ( Property p : attribute.getProperties( "foo" ) ) {
        p.getName().getLocalPart() == "foo";
    }

Often it is known in advance that a single instance of a particular property exists. When this is the case the getProperty(Name) and getProperty(String) methods can be used to get direct access to the property. 
    ComplexAttribute attribute = ...;

    //get the single foo attribute
    Property foo = attribute.getProperty( "foo" );

Xpath and Query Language Access

The above property access methods perform an exact match on property name against the name passed in. However, often it is necesary to access properties via a query language such as xpath.

For instance.the expression "//foo" should return all the properties named "foo". Or the expression "foo/bar" should return the "bar" property nested inside of the "foo" property. In these cases, an Expression must be used: 

   ComplexAttribute attribute = ...;

   //get the 'foo/bar' property
   FilterFactory factory = ...;
   PropertyName xpath = factory.property( "foo/bar" );
   Property bar = xpath.evaluate( attribute );
Author:
Jody Garnett, Refractions Research, Gabriel Roldan, Axios Engineering, Justin Deoliveira, The Open Planning Project

  • Method Details

    • getType

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

    • setValue

      void setValue(Collection<Property> values)
      Sets the contained properties of the complex attribute.

      The values should match the structure defined by getDescriptor().

    • getValue

      Collection<? extends Property> getValue()
      Override of Property.getValue() which returns the collection of Property which make up the value of the complex attribute.
      Specified by:
      getValue in interface Property
      Returns:
      The value of the property.

    • getProperties

      Collection<Property> getProperties(Name name)
      Returns a subset of the properties of the complex attribute which match the specified name.

      The name parameter is matched against each contained Property.getName(), those that are equal are returned.

      Parameters:
      name - The name of the properties to return.
      Returns:
      The collection of properties which match the specified name, or an empty collection if no such properties match.

    • getProperty

      Property getProperty(Name name)
      Returns single property of the complex attribute which matches the specified name.

      Note: This method is a convenience and care should be taken when calling it if more then a single property matches name. In such a case the first encountered property in which Property.getName() is equal to name is returned, and no order is guaranteed.

      This method is a safe convenience for: getProperties(name).iterator().next().

      In the event that no property matches the specified name null is returned.

      Parameters:
      name - The name of the property to return.
      Returns:
      The property matching the specified name, or null.

    • getProperties

      Collection<Property> getProperties(String name)
      Returns a subset of the properties of the complex attribute which match the specified name.

      This method is a convenience for getProperties(Name) in which Name.getNamespaceURI() is null.

      Note: Special care should be taken when using this method in the case that two properties with the same local name but different namespace uri exist. For this reason using getProperties(Name) is safer.

      Parameters:
      name - The local name of the properties to return.
      Returns:
      The collection of properties which match the specified name, or an empty collection if no such properties match.
      See Also:

    • getProperties

      Collection<Property> getProperties()
      Complete collection of properties.

      This method is a convenience method for calling (Collection) getValue().

      Returns:
      The complete collection of properties.

    • getProperty

      Property getProperty(String name)
      Returns single property of the complex attribute which matches the specified name.

      This method is a convenience for getProperty(Name) in which Name.getNamespaceURI() is null.

      Note: This method is a convenience and care should be taken when calling it if more then a single property matches name. In such a case the first encountered property in which Property.getName() is matches name is returned, and no order is guaranteed.

      Note: Special care should be taken when using this method in the case that two properties with the same local name but different namespace uri exist. For this reason using getProperties(Name) is safer.

      Parameters:
      name - The local name of the property to return.
      Returns:
      The property matching the specified name, or null.

    • validate

      void validate() throws IllegalAttributeException
      Check the properties against the constraints provided by their AttributeDescriptors.

      Please note this method checks minOccurs and maxOccurs information; and calls each Attribute.validate on each entry in turn (in order to check isNillable, binding and restrictions).

      Specified by:
      validate in interface Attribute
      Throws:
      IllegalAttributeException - If any attribute fails validation