eu.crisis_economics.abm.markets.clearing.heterogeneous.MixedClearingNetworkNode.java Source code

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Here is the source code for eu.crisis_economics.abm.markets.clearing.heterogeneous.MixedClearingNetworkNode.java

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/*
 * This file is part of CRISIS, an economics simulator.
 * 
 * Copyright (C) 2015 John Kieran Phillips
 *
 * CRISIS is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * CRISIS 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 CRISIS.  If not, see <http://www.gnu.org/licenses/>.
 */

package eu.crisis_economics.abm.markets.clearing.heterogeneous;

import java.util.ArrayList;
import java.util.BitSet;
import java.util.List;

import org.apache.commons.math3.exception.NullArgumentException;

/**
  * A node for a heterogenous clearing network. This class
  * computes, and stores, the response of the node to the
  * connections (edges) between itself and neighbording nodes.
  * For nodes on the supply side, edges connect to a subset
  * of nodes on the demand side. Conversely for demand nodes.
  */
class MixedClearingNetworkNode implements Node {
    private Object representedObject;
    private MarketResponseFunction responseFunction;
    private String uniqueID;

    private List<SingletonEdge> edges;
    private List<Double> edgeResponses;

    protected MixedClearingNetworkNode(final Object representedObject,
            final MarketResponseFunction responseFunction, final String uniqueID) {
        if (representedObject == null || responseFunction == null || uniqueID == null)
            throw new NullArgumentException();
        if (uniqueID.isEmpty())
            throw new IllegalArgumentException("HeterogeneousClearingNode: specified ID is an emptry string.");
        this.representedObject = representedObject;
        this.responseFunction = responseFunction;
        this.edges = new ArrayList<SingletonEdge>();
        this.edgeResponses = new ArrayList<Double>();
        this.uniqueID = uniqueID;
    }

    // Collect connected edge rates into an array.
    private MarketResponseFunction.TradeOpportunity[] collectEdgeRates() {
        final MarketResponseFunction.TradeOpportunity[] result = new MarketResponseFunction.TradeOpportunity[edges
                .size()];
        if (edgeIndicesForCompleteResponseUpdate == null) {
            edgeIndicesForCompleteResponseUpdate = new int[edges.size()];
            for (int i = 0; i < edges.size(); ++i)
                edgeIndicesForCompleteResponseUpdate[i] = i;
        }
        for (int i = 0; i < result.length; ++i) {
            final SingletonEdge edge = edges.get(i);
            result[i] = MarketResponseFunction.TradeOpportunity.create(getEdgeRate(edge), edge.getResource(),
                    getPartyOverConnection(edge));
        }
        return result;
    }

    @Override
    public int getConnectionIndexOfEdge(final SingletonEdge edge) {
        return edge.getConnectionIndex(this);
    }

    @Override
    public String getPartyOverConnection(final SingletonEdge edge) {
        return edge.getUniquePartyOverConnection(this);
    }

    @Override
    public final double getEdgeRate(SingletonEdge edge) {
        return edge.getEdgeRate();
    }

    /**
      * Compute, and commit, the response of the node to the
      * edge with the given connection index.
      */
    private void updateResponseForEdges(final int[] edgeIndicesToRecalculate,
            final MarketResponseFunction.TradeOpportunity[] edgeRates) {
        if (edgeIndicesToRecalculate.length == 0)
            return;
        double[] result = responseFunction.getValue(edgeIndicesToRecalculate, edgeRates);
        for (int i = 0; i < edgeIndicesToRecalculate.length; ++i)
            edgeResponses.set(edgeIndicesToRecalculate[i], result[i]);
    }

    private MarketResponseFunction.TradeOpportunity[] knownEdgeRates;
    private int[] edgeIndicesForCompleteResponseUpdate;
    private BitSet edgeRateIsUpdated;

    /**
      * Update (recalculate) the response of this node to a 
      * given connecting edge.
      */
    @Override
    public final void flagEdgeResponseForUpdate(final SingletonEdge edge) {
        final int connectionIndex = getConnectionIndexOfEdge(edge);
        if (knownEdgeRates == null) {
            knownEdgeRates = collectEdgeRates();
            edgeRateIsUpdated = new BitSet(knownEdgeRates.length);
            edgeRateIsUpdated.flip(0, knownEdgeRates.length);
        } else {
            knownEdgeRates[connectionIndex].setRate(getEdgeRate(edge));
            edgeRateIsUpdated.set(connectionIndex);
        }
    }

    /**
      * Recompute responses for all flagged connections.
      */
    @Override
    public final void recomputePendingEdgeResponses() {
        int[] edgesToUpdate = new int[edgeRateIsUpdated.cardinality()];
        int counter = 0;
        for (int nextConnection = edgeRateIsUpdated.nextSetBit(
                0); nextConnection >= 0; nextConnection = edgeRateIsUpdated.nextSetBit(nextConnection + 1)) {
            edgesToUpdate[counter++] = nextConnection;
            nextConnection = edgeRateIsUpdated.nextSetBit(nextConnection);
        }
        updateResponseForEdges(edgesToUpdate, knownEdgeRates);
        edgeRateIsUpdated.clear();
    }

    /**
      * Update (recalculate) the response of this node to all
      * connecting edges.
      */
    @Override
    public final void updateAllEdgeResponses() {
        MarketResponseFunction.TradeOpportunity[] edgeRates = collectEdgeRates();
        updateResponseForEdges(edgeIndicesForCompleteResponseUpdate, edgeRates);
    }

    /**
      * Get the (stored) response of the node to the given edge.
      */
    @Override
    public final Double getResponseToEdge(SingletonEdge edge) {
        return edgeResponses.get(getConnectionIndexOfEdge(edge));
    }

    /** Latch an edge to this node. */
    @Override
    public final int connectEdge(SingletonEdge edge) {
        if (edge == null)
            throw new NullArgumentException();
        edges.add(edge);
        edgeResponses.add(0.);
        return (edges.size() - 1);
    }

    /**
      * Get the object this node represents. This method cannot
      * return null.
      */
    @Override
    public final Object getObject() {
        return representedObject;
    }

    /**
      * Get the response function of this node.
      */
    @Override
    public final MarketResponseFunction getResponseFunction() {
        return responseFunction;
    }

    /**
      * Get the unique ID of this node.
      **/
    @Override
    public final String getUniqueID() {
        return uniqueID;
    }
}