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.common.Formatter;
020
021/**
022 * A simple Formatter falling back to the objects toString() method.
023 *
024 * @param <T>
025 */
026public class ToStringFormatter<T> implements Formatter<T> {
027
028    private final String nullString;
029
030    public ToStringFormatter() {
031        this("null");
032    }
033
034    public ToStringFormatter(String nullString) {
035        this.nullString = nullString;
036    }
037
038    public String format(T obj) {
039        return obj != null ? obj.toString() : nullString;
040    }
041
042}