Copyright (c) 2000, 2013 IBM Corporation and others.
This program and the accompanying materials
are made available under the terms of the Eclipse Public License 2.0
which accompanies this distribution, and is available at
https://www.eclipse.org/legal/epl-2.0/
SPDX-License-Identifier: EPL-2.0
Contributors:
    IBM Corporation - initial API and implementation
/*******************************************************************************
 * Copyright (c) 2000, 2013 IBM Corporation and others.
 *
 * This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License 2.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-2.0/
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.debug.internal.core.sourcelookup;

import java.util.Comparator;

Comparator for source locator mementos. Ignores whitespace differences.
Since:
3.0/**
 * Comparator for source locator mementos. Ignores whitespace differences.
 *
 * @since 3.0
 */
public class SourceLocatorMementoComparator implements Comparator<String> {

	@Override
	public int compare(String o1, String o2) {
		String m1 = o1;
		String m2 = o2;
		int i1 = 0, i2 = 0;
		while (i1 < m1.length()) {
			i1 = skipWhitespace(m1, i1);
			i2 = skipWhitespace(m2, i2);
			if (i1 < m1.length() && i2 < m2.length()) {
				if (m1.charAt(i1) != m2.charAt(i2)) {
					return -1;
				}
				i1++;
				i2++;
			} else {
				if (i2 < m2.length()) {
					return -1;
				}
				return 0;
			}
		}
		return 0;
	}

	private int skipWhitespace(String string, int offset) {
		int off = offset;
		while (off < string.length() && Character.isWhitespace(string.charAt(off))) {
			off++;
		}
		return off;
	}
}