plugins/org.eclipse.dltk.javascript.parser/src/org/eclipse/dltk/javascript/parser/LineTracker.java

/*******************************************************************************
 * Copyright (c) 2010 xored software, Inc.
 *
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     xored software, Inc. - initial API and Implementation (Alex Panchenko)
 *******************************************************************************/
package org.eclipse.dltk.javascript.parser;

import org.antlr.runtime.CommonToken;
import org.antlr.runtime.Token;
import org.eclipse.dltk.core.ISourceRange;
import org.eclipse.dltk.core.SourceRange;
import org.eclipse.dltk.core.builder.ISourceLineTracker;

class LineTracker {

	private final ISourceLineTracker lineTracker;

	public LineTracker(ISourceLineTracker lineTracker) {
		this.lineTracker = lineTracker;
	}

	public int getOffset(int line, int column) {
		return line > 0 ? lineTracker.getLineOffset(line - 1)
				+ Math.max(column, 0) : 0;
	}

	public final int getLineNumberOfOffset(int offset) {
		return lineTracker.getLineNumberOfOffset(offset);
	}

	public final int getLength() {
		return lineTracker.getLength();
	}

	public final int getNumberOfLines() {
		return lineTracker.getNumberOfLines();
	}

	public int getOffset(Token token) {
		if (token.getLine() >= lineTracker.getNumberOfLines()
				&& token instanceof CommonToken) {
			final CommonToken commonToken = (CommonToken) token;
			if (commonToken.getStartIndex() <= lineTracker.getLength()) {
				return commonToken.getStartIndex();
			}
		}
		return getOffset(token.getLine(), token.getCharPositionInLine());
	}

	public int length(Token token) {
		final String sm = token.getText();
		return sm != null ? sm.length() : 1;
	}

	public ISourceRange toSourceRange(Token token) {
		return new SourceRange(getOffset(token), length(token));
	}

}