org.sourcepit.ltk.jcomment.AbstractCommentLexer.java Source code

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Here is the source code for org.sourcepit.ltk.jcomment.AbstractCommentLexer.java

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/*
 * Copyright 2015 Bernd Vogt and others.
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 * http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.sourcepit.ltk.jcomment;

import org.antlr.v4.runtime.CharStream;
import org.antlr.v4.runtime.CommonToken;
import org.antlr.v4.runtime.Lexer;
import org.antlr.v4.runtime.Token;

/**
 * @author Bernd Vogt <bernd.vogt@sourcepit.org>
 */
public abstract class AbstractCommentLexer extends Lexer {

    public static final int JAVA_DOC_LINE_PREFIX = 2;

    protected boolean allowBlockTag;

    public AbstractCommentLexer(CharStream input) {
        super(input);
    }

    private Token cachedToken;

    @Override
    public Token nextToken() {
        if (cachedToken != null) {
            Token t = cachedToken;
            cachedToken = null;
            return t;
        }
        Token t = _nextToken();
        CommonToken aggregate = null;
        while (t.getType() == CommentLexer.CommentText) {
            if (aggregate == null) {
                aggregate = (CommonToken) t;
            } else {
                aggregate.setStopIndex(t.getStopIndex());
            }
            t = _nextToken();
        }
        if (aggregate == null) {
            return t;
        }
        cachedToken = t;
        return aggregate;
    }

    private Token _nextToken() {
        Token token = super.nextToken();
        switch (token.getType()) {
        case CommentLexer.DocCommentStart:
        case CommentLexer.BlockCommentStart:
        case CommentLexer.BlockCommentLinePrefix:
        case CommentLexer.Nl:
            allowBlockTag = true;
            break;
        case CommentLexer.Ws:
            break;
        default:
            allowBlockTag = false;
            break;
        }
        return token;
    }

    static boolean isTagStart(int c) {
        if (c >= 'A' && c <= 'Z') {
            return true;
        }
        if (c >= 'a' && c <= 'z') {
            return true;
        }
        return false;
    }

    static boolean isChar(int c, int... chars) {
        for (int _c : chars) {
            if (c == _c) {
                return true;
            }
        }
        return false;
    }

    static boolean isNotChar(int c, int... chars) {
        for (int _c : chars) {
            if (c == _c) {
                return false;
            }
        }
        return true;
    }

    protected int LA(int i) {
        return _input.LA(i);
    }
}