com.github.rinde.logistics.pdptw.mas.comm.BlackboardUser.java Source code

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Here is the source code for com.github.rinde.logistics.pdptw.mas.comm.BlackboardUser.java

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/*
 * Copyright (C) 2013-2016 Rinde van Lon, iMinds-DistriNet, KU Leuven
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *         http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.github.rinde.logistics.pdptw.mas.comm;

import static com.google.common.base.MoreObjects.toStringHelper;
import static com.google.common.base.Preconditions.checkArgument;
import static com.google.common.collect.Sets.newLinkedHashSet;
import static java.util.Collections.unmodifiableSet;

import java.util.Set;

import com.github.rinde.rinsim.core.model.pdp.PDPModel;
import com.github.rinde.rinsim.core.model.pdp.Parcel;
import com.github.rinde.rinsim.core.model.pdp.Vehicle;
import com.github.rinde.rinsim.core.model.road.RoadModel;
import com.github.rinde.rinsim.event.Event;
import com.github.rinde.rinsim.event.EventDispatcher;
import com.github.rinde.rinsim.event.Listener;
import com.github.rinde.rinsim.util.StochasticSupplier;
import com.github.rinde.rinsim.util.StochasticSuppliers;
import com.google.common.base.Optional;
import com.google.common.collect.Sets;

/**
 * This {@link Communicator} implementation allows communication via a
 * blackboard system. It requires the {@link BlackboardCommModel}.
 * @author Rinde van Lon
 */
public class BlackboardUser implements Communicator {

    private Optional<BlackboardCommModel> bcModel;
    private final EventDispatcher eventDispatcher;
    private final Set<Parcel> claimedParcels;

    /**
     * Constructor.
     */
    public BlackboardUser() {
        eventDispatcher = new EventDispatcher(CommunicatorEventType.values());
        bcModel = Optional.absent();
        claimedParcels = newLinkedHashSet();
    }

    /**
     * @param model Injects the {@link BlackboardCommModel}.
     */
    public void init(BlackboardCommModel model) {
        bcModel = Optional.of(model);
    }

    @Override
    public void waitFor(Parcel p) {
    }

    /**
     * Lay a claim on the specified {@link Parcel}.
     * @param p The parcel to claim.
     */
    @Override
    public void claim(Parcel p) {
        checkArgument(!claimedParcels.contains(p), "Parcel %s is already claimed.", p);
        // forward call to model
        bcModel.get().claim(this, p);
        claimedParcels.add(p);
    }

    @Override
    public void unclaim(Parcel p) {
        checkArgument(claimedParcels.contains(p), "Parcel %s is not claimed.", p);
        bcModel.get().unclaim(this, p);
        claimedParcels.remove(p);
    }

    @Override
    public void done() {
        claimedParcels.clear();
    }

    /**
     * Notifies this blackboard user of a change in the environment.
     */
    public void update() {
        eventDispatcher.dispatchEvent(new Event(CommunicatorEventType.CHANGE, this));
    }

    @Override
    public void addUpdateListener(Listener l) {
        eventDispatcher.addListener(l, CommunicatorEventType.CHANGE);
    }

    @Override
    public Set<Parcel> getParcels() {
        return Sets.union(bcModel.get().getUnclaimedParcels(), claimedParcels);
    }

    @Override
    public Set<Parcel> getClaimedParcels() {
        return unmodifiableSet(claimedParcels);
    }

    @Override
    public String toString() {
        return toStringHelper(this).addValue(Integer.toHexString(hashCode())).toString();
    }

    // not needed
    @Override
    public void init(RoadModel rm, PDPModel pm, Vehicle v) {
    }

    /**
     * @return A {@link StochasticSupplier} that supplies {@link BlackboardUser}
     *         instances.
     */
    public static StochasticSupplier<BlackboardUser> supplier() {
        return new StochasticSuppliers.AbstractStochasticSupplier<BlackboardUser>() {
            private static final long serialVersionUID = 1701618808844264668L;

            @Override
            public BlackboardUser get(long seed) {
                return new BlackboardUser();
            }
        };
    }

}