/*
 *    GeoTools - The Open Source Java GIS Toolkit
 *    http://geotools.org
 *
 *    (C) 2011, Open Source Geospatial Foundation (OSGeo)
 *    (C) 2003-2005, Open Geospatial Consortium Inc.
 *    
 *    All Rights Reserved. http://www.opengis.org/legal/
 */
package org.opengis.parameter;

import org.opengis.referencing.IdentifiedObject;
import org.opengis.annotation.UML;
import org.opengis.annotation.Extension;

import static org.opengis.annotation.Obligation.*;
import static org.opengis.annotation.Specification.*;


/**
 * Abstract definition of a parameter or group of parameters used by an operation method.
 *
 *
 * @source $URL: http://svn.osgeo.org/geotools/trunk/modules/library/opengis/src/main/java/org/opengis/parameter/GeneralParameterDescriptor.java $
 * @version <A HREF="http://portal.opengeospatial.org/files/?artifact_id=6716">Abstract specification 2.0</A>
 * @author  Martin Desruisseaux (IRD)
 * @author  Jody Garnett (Refractions Research)
 * @since   GeoAPI 2.0
 *
 * @see GeneralParameterValue
 */
@UML(identifier="CC_GeneralOperationParameter", specification=ISO_19111)
public interface GeneralParameterDescriptor extends IdentifiedObject {
    /**
     * Creates a new instance of {@linkplain GeneralParameterValue parameter value or group}
     * initialized with the {@linkplain ParameterDescriptor#getDefaultValue default value(s)}.
     * The {@linkplain GeneralParameterValue#getDescriptor parameter value descriptor} for
     * the created parameter value(s) will be {@code this} object.
     *
     * @return A new parameter initialized to its default value.
     */
    @Extension
    GeneralParameterValue createValue();

    /**
     * The minimum number of times that values for this parameter group or
     * parameter are required. The default value is one. A value of 0 means
     * an optional parameter.
     *
     * @return The minimum occurence.
     *
     * @see #getMaximumOccurs
     */
    @UML(identifier="minimumOccurs", obligation=OPTIONAL, specification=ISO_19111)
    int getMinimumOccurs();

    /**
     * The maximum number of times that values for this parameter group or
     * parameter can be included. For a {@linkplain ParameterDescriptor single parameter},
     * the value is always 1. For a {@linkplain ParameterDescriptorGroup parameter group},
     * it may vary. The default value is one.
     *
     * @return The maximum occurence.
     *
     * @see #getMinimumOccurs
     */
    @UML(identifier="CC_OperationParameterGroup.maximumOccurs", obligation=OPTIONAL, specification=ISO_19111)
    int getMaximumOccurs();
}