Huffman.java

 public static Map<Character, EncodedString> buildEncodingMap(Node tree) {
        return buildEncodingMap(tree, new EncodedString());
    }

    public static Map<Character, EncodedString> buildEncodingMap(Node node, EncodedString string)
    {
        if (node.character != 0)
        {
            // The node has a character, frequency mapping
            HashMap<Character, EncodedString> map = new HashMap<Character, EncodedString>();
            map.put(node.character, string);
            return map;
        }
        else
        {
            // Traverse the tree, and recursively build the map
            return traverseAndBuild(node, string);
        }
    }


    protected static Map<Character, EncodedString> traverseAndBuild(Node node, EncodedString string)
    {
        Iterator iter = string.iterator();

        EncodedString left = new EncodedString();
        EncodedString right = new EncodedString();

        while(iter.hasNext())
        {
            Byte next = (Byte) iter.next();
            if (next == EncodedString.ONE)
            {
                left.one();
            }
            else if (next == EncodedString.ZERO)
            {
                left.zero();
            }
        }
        left.zero();

        iter = string.iterator();
        while(iter.hasNext())
        {
            Byte next = (Byte) iter.next();
            if (next == EncodedString.ONE)
            {
                right.one();
            }
            else if (next == EncodedString.ZERO)
            {
                right.zero();
            }
        }
        right.one();

        return mergeMaps(buildEncodingMap(node.left, left), buildEncodingMap(node.right, right));
    }