RouteMatcher.java

/* This program is free software: you can redistribute it and/or
 modify it under the terms of the GNU Lesser General Public License
 as published by the Free Software Foundation, either version 3 of
 the License, or (at your option) any later version.

 This program is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 GNU General Public License for more details.

 You should have received a copy of the GNU General Public License
 along with this program.  If not, see <http://www.gnu.org/licenses/>. */

package org.opentripplanner.routing.core;

import java.io.Serializable;
import java.util.HashSet;

import org.onebusaway.gtfs.model.AgencyAndId;
import org.onebusaway.gtfs.model.Route;
import org.opentripplanner.common.model.T2;
import org.opentripplanner.gtfs.GtfsLibrary;

/**
 * A RouteMatcher is a collection of routes based on IDs, short name and/or agency IDs.
 * 
 * We currently support route full IDs (agency ID + route ID), agency ID + route name, or route name only. Support for other matching expression can
 * be easily added later on.
 */
public class RouteMatcher implements Cloneable, Serializable {
    private static final long serialVersionUID = 8066547338465440312L;

    /* Set of full matching route ids (agency ID + route ID) */
    private HashSet<AgencyAndId> agencyAndRouteIds = new HashSet<AgencyAndId>();

    /* Set of full matching route code/names (agency ID + route code/name) */
    private HashSet<T2<String, String>> agencyIdAndRouteNames = new HashSet<T2<String, String>>();

    /* Set of matching route names (without specifying an agency ID) */
    private HashSet<String> routeNames = new HashSet<String>();

    private static RouteMatcher EMPTY_MATCHER = new RouteMatcher();

    private RouteMatcher() {
    }

    /**
     * Return an empty matcher (which match no routes).
     */
    public static RouteMatcher emptyMatcher() {
        return EMPTY_MATCHER;
    }

    /**
     * Build a new RouteMatcher from a string representation.
     * 
     * @param routeSpecList A comma-separated list of route spec, each of the format [agencyId]_[routeName]_[routeId] Please note that this format is
     *        not really intuitive as it does not follow the OBA-gtfslib AgencyAndId standard ('agencyID_routeId'). This was kept for
     *        backward-compatibility purposes. If the original routeName contains some "_" each *must* be replaced by a space.
     * @return A RouteMatcher
     * @throws IllegalArgumentException If the string representation is invalid.
     */
    public static RouteMatcher parse(String routeSpecList) {
        if (routeSpecList == null)
            return emptyMatcher();
        RouteMatcher retval = new RouteMatcher();
        int n = 0;
        for (String element : routeSpecList.split(",")) {
            if (element.length() == 0)
                continue;
            n++;
            String[] routeSpec = element.split("_", 3);
            if (routeSpec.length != 2 && routeSpec.length != 3) {
                throw new IllegalArgumentException("Wrong route spec format: " + element);
            }
            String agencyId = routeSpec[0];
            if (agencyId.length() == 0)
                agencyId = null;
            String routeName = routeSpec[1];
            if (routeName.length() == 0)
                routeName = null;
            String routeId = routeSpec.length > 2 ? routeSpec[2] : null;
            if (routeId != null && routeId.length() == 0)
                routeId = null;
            if (agencyId != null && routeId != null && routeName == null) {
                // Case 1: specified agency ID and route ID but no route name
                retval.agencyAndRouteIds.add(new AgencyAndId(agencyId, routeId));
            } else if (agencyId != null && routeName != null && routeId == null) {
                // Case 2: specified agency ID and route name but no route ID
                retval.agencyIdAndRouteNames.add(new T2<String, String>(agencyId, routeName));
            } else if (agencyId == null && routeName != null && routeId == null) {
                // Case 3: specified route name only
                retval.routeNames.add(routeName);
            } else {
                throw new IllegalArgumentException("Wrong route spec format: " + element);
            }
        }
        if (n == 0)
            return emptyMatcher();
        return retval;
    }

    public boolean matches(Route route) {
        if (this == EMPTY_MATCHER)
            return false;
        if (agencyAndRouteIds.contains(route.getId()))
            return true;
        String routeName = GtfsLibrary.getRouteName(route).replace("_", " ");
        if (agencyIdAndRouteNames.contains(new T2<String, String>(route.getId().getAgencyId(),
                routeName)))
            return true;
        if (routeNames.contains(routeName))
            return true;
        return false;
    }

    public String asString() {
        StringBuilder builder = new StringBuilder();
        for (AgencyAndId agencyAndId : agencyAndRouteIds) {
            builder.append(agencyAndId.getAgencyId() + "__" + agencyAndId.getId());
            builder.append(",");
        }
        for (T2<String, String> agencyIdAndRouteName : agencyIdAndRouteNames) {
            builder.append(agencyIdAndRouteName.getFirst() + "_" + agencyIdAndRouteName.getSecond());
            builder.append(",");
        }
        for (String routeName : routeNames) {
            builder.append("_" + routeName);
            builder.append(",");
        }
        if (builder.length() > 0) {
            builder.setLength(builder.length() - 1);
        }
        return builder.toString();
    }

    @Override
    public String toString() {
        return String.format(
                "RouteMatcher<agencyAndRouteIds=%s agencyIdAndRouteNames=%s routeNames=%s>",
                agencyAndRouteIds, agencyIdAndRouteNames, routeNames);
    }

    @Override
    public boolean equals(Object another) {
        if (another == null || !(another instanceof RouteMatcher))
            return false;
        if (another == this)
            return true;
        RouteMatcher anotherMatcher = (RouteMatcher) another;
        return agencyAndRouteIds.equals(anotherMatcher.agencyAndRouteIds)
                && agencyIdAndRouteNames.equals(anotherMatcher.agencyIdAndRouteNames)
                && routeNames.equals(anotherMatcher.routeNames);
    }

    @Override
    public int hashCode() {
        return agencyAndRouteIds.hashCode() + agencyIdAndRouteNames.hashCode()
                + routeNames.hashCode();
    }

    public RouteMatcher clone() {
        try {
            return (RouteMatcher) super.clone();
        } catch (CloneNotSupportedException e) {
            /* this will never happen since our super is the cloneable object */
            throw new RuntimeException(e);
        }
    }
}