import brs.*;

/**
 * Computes a String representation of a BiTree in in-order traversal.
 * Has extra new line characters when left and/or right subtrees are empty.
 * These new line characters can ge best handled by helper visitors.
 * @author D.X. Nguyen - Copyright 2001 - All Rights Reserved
 */
public class DictToString implements IVisitor {

    public static final DictToString Singleton = new DictToString();

    private DictToString() {
    }

    public Object emptyCase(BiTree host, Object inp) {
        return "";
    }

    public Object nonEmptyCase(BiTree host, Object inp) {
        return host.getLeftSubTree().execute(this, null) + "\n"
            + host.getRootDat().toString() + "\n"
            + host.getRightSubTree().execute(this, null);
    }
}