Agent.java

package randomPackage;

import java.util.ArrayList;

public abstract class Agent {

    // Instance Variables
    protected static StateMachineEnvironment env;
    protected char[] alphabet;
    protected ArrayList<Episode> episodicMemory;
    protected boolean[] sensor;

    protected int numStates = 1;

    protected static final int IS_NEW_STATE = 0;
    protected static final int IS_GOAL = 1;

    protected static final int INIT_STATE = 1; // This numbers the first state
                                               // for the machine as state 1
    protected static final char UNKNOWN_COMMAND = ' ';

    // sensor Values (encoded for Episode use)
    protected static final int NO_SENSORS_ON = 0;
    protected static final int MYSTERY_SENSOR_ON = 1;
    protected static final int MYSTERY_AND_GOAL_ON = 2;

    /**
     * RandomAgent Constructor.
     */
    public Agent() {
        // mk new SME for the agent to navigate
        env = new StateMachineEnvironment();

        // Copies the alphabet from the SME to the agent
        alphabet = env.getAlphabet();

        // Allocate the episodicMemory
        episodicMemory = new ArrayList<Episode>();

        // Init the sensor array to being false for goal and new state
        sensor = new boolean[2];
        sensor[IS_NEW_STATE] = false;
        sensor[IS_GOAL] = false;
        episodicMemory.add(new Episode(UNKNOWN_COMMAND, NO_SENSORS_ON,
                INIT_STATE));

    }

    /**
     * RandomAgent Ctor
     */
    public Agent(StateMachineEnvironment environment) {
        env = environment;

        // Copies the alphabet from the SME to the agent
        alphabet = env.getAlphabet();

        // Allocate the episodicMemory
        episodicMemory = new ArrayList<Episode>();

        // Init the sensor array to being false for goal and new state
        sensor = new boolean[2];
        sensor[IS_NEW_STATE] = false;
        sensor[IS_GOAL] = false;
        episodicMemory.add(new Episode(UNKNOWN_COMMAND, NO_SENSORS_ON,
                INIT_STATE));

    }

    /**
     * this method finds the random path to the goal
     */
    public void findRandomPath() {

        int length = this.alphabet.length; // # char in alpha
        char letter;
        // numStates++; //starting at 2 because this is the next state in the
        // memory for the episodes

        do {
            numStates++;
            letter = randomChar(length);
            sensor = this.env.tick(letter); // updates sensor
            // encode sensors to make into an episode to store in memory
            int encodedSensorValue = encodeSensors(sensor);
            episodicMemory.add(new Episode(letter, encodedSensorValue,
                    numStates));

        } while (!sensor[IS_GOAL]);
    }

    /**
     * 
     */
    protected int encodeSensors(boolean[] sensors) {

        int encodedResult;
        if (sensors[IS_GOAL])
            encodedResult = MYSTERY_AND_GOAL_ON;
        else if (sensors[IS_NEW_STATE])
            encodedResult = MYSTERY_SENSOR_ON;
        else
            encodedResult = NO_SENSORS_ON;

        return encodedResult;
    }

    /**
     * returns a random char that is in the alphabet that the agent is using
     */
    protected char randomChar(int length) {

        int randomLetter = (int) (Math.random() * length);
        char letter = this.alphabet[randomLetter];
        return letter;
    }

    /**
     * printPath
     */
    public void printPath() {
        for (int i = 0; i < this.episodicMemory.size(); i++) {
            System.out.print(this.episodicMemory.get(i).command);
        }
        System.out.println();
        System.out.println(this.episodicMemory.size() - 1);
    }

}