source: anac2021/dicehaggler/src/main/java/geniusweb/exampleparties/learningagent/PersistentState.java@ 62

package geniusweb.exampleparties.learningagent; // TODO: change name

import java.util.HashMap;
import java.util.Map;

import com.fasterxml.jackson.annotation.JsonAutoDetect;
import com.fasterxml.jackson.annotation.JsonAutoDetect.Visibility;

/**
 * This class can hold the persistent state of your agent. You can off course
 * also write something else to the file path that is provided to your agent,
 * but this provides an easy usable method. This object is serialized using
 * Jackson. NOTE that Jackson can serialize many default java classes, but not
 * custom classes out-of-the-box.
 */
@JsonAutoDetect(fieldVisibility = Visibility.ANY, getterVisibility = Visibility.NONE, setterVisibility = Visibility.NONE)
public class PersistentState {

    private Double averageUtility = 0.0;
    private Integer negotiations = 0;
    private Map<String, Double> avgMaxUtilityOpponent = new HashMap<String, Double>();
    private Map<String, Integer> opponentEncounters = new HashMap<String, Integer>();

    /**
     * Update the persistent state with a negotiation data of a previous negotiation
     * session
     * 
     * @param negotiationData NegotiationData class holding the negotiation data
     *                        that is obtain during a negotiation session.
     */
    public void update(NegotiationData negotiationData) {
        // Keep track of the average utility that we obtained
        this.averageUtility = (this.averageUtility * negotiations + negotiationData.getAgreementUtil())
                / (negotiations + 1);

        // Keep track of the number of negotiations that we performed
        negotiations++;

        // Get the name of the opponent that we negotiated against
        String opponent = negotiationData.getOpponentName();

        // Check for safety
        if (opponent != null) {
            // Update the number of encounters with an opponent
            Integer encounters = opponentEncounters.containsKey(opponent) ? opponentEncounters.get(opponent) : 0;
            opponentEncounters.put(opponent, encounters + 1);
            // Track the average value of the maximum that an opponent has offered us across
            // multiple negotiation sessions
            Double avgUtil = avgMaxUtilityOpponent.containsKey(opponent) ? avgMaxUtilityOpponent.get(opponent) : 0.0;
            avgMaxUtilityOpponent.put(opponent,
                    (avgUtil * encounters + negotiationData.getMaxReceivedUtil()) / (encounters + 1));
        }
    }

    public Double getAvgMaxUtility(String opponent) {
        if (avgMaxUtilityOpponent.containsKey(opponent)) {
            return avgMaxUtilityOpponent.get(opponent);
        }
        return null;
    }

    public Integer getOpponentEncounters(String opponent) {
        if (opponentEncounters.containsKey(opponent)) {
            return opponentEncounters.get(opponent);
        }
        return null;
    }

    public Boolean knownOpponent(String opponent) {
        return opponentEncounters.containsKey(opponent);
    }
}