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.matchers;
018
019import org.parboiled.MatcherContext;
020import org.parboiled.matchervisitors.MatcherVisitor;
021
022import static org.parboiled.common.Preconditions.checkArgNotNull;
023import static org.parboiled.common.Preconditions.checkArgument;
024import static org.parboiled.common.StringUtils.escape;
025
026/**
027 * A {@link Matcher} matching a single character out of a given range of characters.
028 */
029public class CharRangeMatcher extends AbstractMatcher {
030    public final char cLow;
031    public final char cHigh;
032
033    public CharRangeMatcher(char cLow, char cHigh) {
034        super(escape(cLow) + ".." + escape(cHigh));
035        checkArgument(cLow < cHigh);
036        this.cLow = cLow;
037        this.cHigh = cHigh;
038    }
039
040    public boolean match(MatcherContext context) {
041        char c = context.getCurrentChar();
042        if (c < cLow || c > cHigh) return false;
043
044        context.advanceIndex(1);
045        context.createNode();
046        return true;
047    }
048
049    public <R> R accept(MatcherVisitor<R> visitor) {
050        checkArgNotNull(visitor, "visitor");
051        return visitor.visit(this);
052    }
053
054}