annis.ql.parser.ListTokenSource.java Source code

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Here is the source code for annis.ql.parser.ListTokenSource.java

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/*
 * Copyright 2013 SFB 632.
 *
 * 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 annis.ql.parser;

import com.google.common.base.Preconditions;
import java.util.List;
import org.antlr.v4.runtime.CharStream;
import org.antlr.v4.runtime.CommonToken;
import org.antlr.v4.runtime.Lexer;
import org.antlr.v4.runtime.Token;
import org.antlr.v4.runtime.TokenFactory;
import org.antlr.v4.runtime.TokenSource;

/**
 *
 * @author Thomas Krause <krauseto@hu-berlin.de>
 */
public class ListTokenSource implements TokenSource {
    private final List<Token> token;
    private TokenFactory factory;
    private final CommonToken eofToken = new CommonToken(Lexer.EOF, "");

    public ListTokenSource(List<Token> token) {
        this.token = token;
        Preconditions.checkNotNull(token);
        Preconditions.checkArgument(!token.isEmpty(), "Internal token list must not be empty");

        for (Token t : token) {
            if (t.getTokenSource() != null) {
                this.factory = t.getTokenSource().getTokenFactory();
                break;
            }
        }
        Preconditions.checkNotNull(this.factory, "Internal token list needs a valid TokenSource");

        Token lastToken = token.get(token.size() - 1);
        eofToken.setLine(lastToken.getLine());
        eofToken.setCharPositionInLine(lastToken.getCharPositionInLine());
    }

    @Override
    public Token nextToken() {
        if (token.isEmpty()) {
            return eofToken;
        } else {
            return token.remove(0);
        }
    }

    @Override
    public int getLine() {
        if (token.isEmpty()) {
            return eofToken.getLine();
        } else {
            return token.get(0).getLine();
        }
    }

    @Override
    public int getCharPositionInLine() {
        if (token.isEmpty()) {
            return eofToken.getCharPositionInLine();
        } else {
            return token.get(0).getCharPositionInLine();
        }
    }

    @Override
    public CharStream getInputStream() {
        if (token.isEmpty()) {
            return eofToken.getInputStream();
        } else {
            return token.get(0).getInputStream();
        }
    }

    @Override
    public String getSourceName() {
        if (token.isEmpty()) {
            return eofToken.getInputStream().getSourceName();
        } else {
            return token.get(0).getInputStream().getSourceName();
        }
    }

    @Override
    public TokenFactory getTokenFactory() {
        return factory;
    }

    @Override
    public void setTokenFactory(TokenFactory factory) {
        this.factory = factory;
    }

}