001/*
002 * Copyright (C) 2009-2011 Mathias Doenitz
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 * http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016
017package org.parboiled.support;
018
019import org.parboiled.Node;
020import org.parboiled.buffers.InputBuffer;
021import org.parboiled.common.Formatter;
022import org.parboiled.common.StringUtils;
023
024import static org.parboiled.common.Preconditions.checkArgNotNull;
025
026/**
027 * A simple {@literal Formatter<Node>} that provides String representation for parse tree nodes.
028 */
029public class NodeFormatter<V> implements Formatter<Node<V>> {
030
031    private final InputBuffer inputBuffer;
032
033    /**
034     * Creates a new NodeFormatter.
035     *
036     * @param inputBuffer the input buffer underlying the parse tree whose nodes are to be formatted.
037     */
038    public NodeFormatter(InputBuffer inputBuffer) {
039        this.inputBuffer = checkArgNotNull(inputBuffer, "inputBuffer");
040    }
041
042    public String format(Node<V> node) {
043        String nodeLabel = node.toString();
044        String nodeText = StringUtils.escape(ParseTreeUtils.getNodeText(node, inputBuffer));
045        return StringUtils.isEmpty(nodeText) ? nodeLabel : nodeLabel + " '" + nodeText + '\'';
046    }
047
048}