Application: gvSIG desktop

 * customize the behavior of the getDataCollection methods, there is an option

 * to set more parameters through the setAttribute method.

 * </p>

 * @author 2009- <a href="cordinyana@gvsig.org">C?sar Ordi?ana</a> - gvSIG team

 */

public interface FeatureQuery extends DataQuery, Cloneable {

	/**

	 * Returns the names of the attributes to load from each {@link Feature}.

	 * @return the attribute names to load

	 */

	String[] getAttributeNames();

	/**

	 * Sets the names of the attributes to load from each {@link Feature}.

	 * @param attributeNames

	 *            the attribute names to load

	 */

	void setAttributeNames(String[] attributeNames);

	/**

	 * Adds the name of an attribute that has to be used to load each

	 * {@link Feature}.

	 * @param attributeName

	 *             the attribute name to load

	 */

        /**

         * Return true if has set attribute names

         * @return true if has attribute names, otherwise false

         */

        boolean hasAttributeNames();

        /**

         * Remove all the attribute names specifieds.

         */

        /**

	 * Returns the names of the attributes that are constants in each {@link Feature}.

	 * These attributes will not be charged.

	 * @return the attribute names that are constant

	 */

	String[] getConstantsAttributeNames();

	/**

	 * Set of attribute names to be treated as constants for each {@link Feature}.

	 * @param attributeNames

	 *            the attribute names to be constants

	 */

	void setConstantsAttributeNames(String[] attributeNames);

	/**

	 * {@link Feature}.

	 * @param attributeName

	 *             the attribute name to be treated as constant

	 */

        /**

         * Return true if has set constants attribute names

         * @return true if has constants attribute names, otherwise false

         */

        boolean hasConstantsAttributeNames();

        /**

         * Remove all the names specified as constants attributes.

         */

        void clearConstantsAttributeNames();

	/**

	 * Sets the {@link FeatureType} of the {@link Feature}s to load. It may be

	 * used as an alternative way to set a subset of the list of attribute names

	 * to load, by creating a sub-FeatureType.

	 * @param featureType

	 *            the feature type of the data to load

	 */

	/**

	 * Returns the {@link FeatureType} id of the {@link Feature}s to load.

	 * @return the {@link FeatureType} id of the {@link Feature}s to load

	 */

	String getFeatureTypeId();

	/**

	 * Sets the {@link FeatureType} id of the {@link Feature}s to load. This way

	 * all {@link Feature} attributes will be loaded.

	 * @param featureTypeId

	 *            the {@link FeatureType} id of the {@link Feature}s to load

	 */

	/**

	 * Returns the filter to apply to the {@link Feature}s to load.

	 * @return the filter

	 */

	Evaluator getFilter();

	/**

	 * Sets the filter to apply to the {@link Feature}s to load.

	 * @param filter

	 *            the filter to apply to the {@link Feature}s to load

	 */

	void setFilter(Evaluator filter);

        void setFilter(String filter);

	/**

	 * Adds a filter to apply to the {@link Feature}s to load. A query

	 * can have more that one filter and all of them are applied when

	 * the query is applied.

         * If filter is null do nothing.

	 * @param filter

	 *             a filter to apply to the {@link Feature}s to load

	 */

	void addFilter(Evaluator filter);

        void addFilter(String filter);

	/**

	 * Returns if a filter has been defined for the query.

	 * @return if a filter has been defined for the query

	 */

	boolean hasFilter();

	/**

	 * Returns the order of the {@link Feature}s to load.

	 * @return the order of the {@link Feature}s to load

	 */

	FeatureQueryOrder getOrder();

	/**

	 * Sets the order of the {@link Feature}s to load.

	 * @param order

	 *            the order of the {@link Feature}s to load

	 */

	/**

	 * Returns if an order has been set for the elements returned by the query.

	 * @return if an order has been set for the elements returned by the query

	 */

	boolean hasOrder();

	 * source, or only used as a hint, so don't rely on it being used, as you

	 * may actually get more values than the limit.

	 * </p>

	 * @return the maximum number of elements to return with this query

	 */

	long getLimit();

	 * source, or only used as a hint, so don't rely on it being used, as you

	 * may actually get more values than the limit.

	 * </p>

	 * @param limit

	 *            the maximum number of elements to return with this query

	 */

	 * block by the data source. This value is only used as a hint to the

	 * underlying data source, as a way to tell how many Features may be read in

	 * a block.

	 * @return the load page size

	 */

	long getPageSize();

	 * block by the data source. This value is only used as a hint to the

	 * underlying data source, as a way to tell how many Features may be read in

	 * a block.

	 * @param pageSize

	 *            the load page size

	 */