/*
  Copyright 2006 by Sean Luke
  Licensed under the Academic Free License version 3.0
  See the file "LICENSE" for more information
*/


package ec.gp;
import ec.*;
import ec.util.*;

/* 
 * GPData.java
 * 
 * Created: Mon Oct 25 19:37:18 1999
 * By: Sean Luke
 */

/**
 * GPData is the parent class of data transferred between GPNodes.
 * If performed correctly, there need be only one GPData instance 
 * ever created in the evaluation of many individuals. 

 <p><b>Default Base</b><br>
 gp.data

 *
 * @author Sean Luke
 * @version 1.0 
 */

public abstract class GPData implements Prototype
    {
    public static final String P_GPDATA = "data";

    /** Modifies gpd so that gpd is equivalent to us. You may
        safely assume that gpd is of the same class as we are.
        Do not share pointers with the other object, except to
        read-only data: instead, copy any read-write data as necessary. */
    public abstract void copyTo(final GPData gpd);

    public Parameter defaultBase()
        {
        return GPDefaults.base().push(P_GPDATA);
        }

    public void setup(final EvolutionState state, final Parameter base)
        {
        }

    public Object clone()
        {
        try { return super.clone(); }
        catch (CloneNotSupportedException e) 
            { throw new InternalError(); } // never happens
        }
    }