teichmann@5863: /* Copyright (C) 2011, 2012, 2013 by Bundesanstalt für Gewässerkunde
teichmann@5863:  * Software engineering by Intevation GmbH
teichmann@5863:  *
teichmann@5994:  * This file is Free Software under the GNU AGPL (>=v3)
teichmann@5863:  * and comes with ABSOLUTELY NO WARRANTY! Check out the
teichmann@5994:  * documentation coming with Dive4Elements River for details.
teichmann@5863:  */
teichmann@5863: 
teichmann@5831: package org.dive4elements.river.artifacts.model.fixings;
bjoern@4442: 
gernotbelger@9415: import static org.dive4elements.river.exports.injector.InjectorConstants.CURRENT_KM;
gernotbelger@9415: 
teichmann@5831: import org.dive4elements.artifacts.CallContext;
teichmann@5831: import org.dive4elements.river.artifacts.model.DataFacet;
teichmann@5831: import org.dive4elements.river.artifacts.states.DefaultState.ComputeType;
bjoern@4442: 
bjoern@4442: /**
bjoern@4442:  * Facet to access the current Km from the context safely
teichmann@4736:  *
bjoern@4442:  * @author <a href="mailto:bjoern.ricks@intevation.de">Björn Ricks</a>
bjoern@4442:  */
gernotbelger@9415: public abstract class FixingsFacet extends DataFacet {
gernotbelger@9415: 
gernotbelger@9415:     private static final long serialVersionUID = 1L;
bjoern@4442: 
bjoern@4442:     public static final Double INVALID_KM = Double.valueOf(-1d);
bjoern@4442: 
bjoern@4442:     public FixingsFacet() {
bjoern@4442:     }
bjoern@4442: 
gernotbelger@9415:     public FixingsFacet(final int index, final String name, final String description, final ComputeType type, final String hash, final String stateId) {
bjoern@4442:         super(index, name, description, type, hash, stateId);
bjoern@4442:     }
bjoern@4442: 
bjoern@4442:     /**
bjoern@4442:      * Returns the current km from the context.
tom@8856:      * If the context is null or doesn't contain a currentKm
tom@8856:      * then a double value of -1 will be returned.
gernotbelger@9415:      *
gernotbelger@9415:      * @param context
gernotbelger@9415:      *            The CallContext instance
bjoern@4442:      * @return the current km as double
bjoern@4442:      */
gernotbelger@9415:     protected final double getCurrentKm(final CallContext context) {
bjoern@4442:         if (context == null) {
bjoern@4442:             return INVALID_KM;
bjoern@4442:         }
gernotbelger@9415:         final Double dkm = (Double) context.getContextValue(CURRENT_KM);
bjoern@4442:         if (dkm == null) {
bjoern@4442:             return INVALID_KM;
bjoern@4442:         }
bjoern@4442:         return dkm.doubleValue();
bjoern@4442:     }
gernotbelger@9415: }