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 * Copyright (c) 2015
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 * DEALINGS IN THE SOFTWARE.
 *******************************************************************************/
package jsettlers.common.logging;

/**
 * this class implements a simple stop watch.
 * 
 * @author Andreas Eberle
 * 
 */
public abstract class StopWatch {

	private long start;

	public StopWatch() {
		restart();
	}

	/**
	 * saves the current time.
	 */
	public final void restart() {
		start = now();
	}

	/**
	 * calculates the difference from start to now and prints the result.
	 * 
	 * @param leadingText
	 *            text to be pretended to the measured difference
	 */
	public void stop(String leadingText) {
		System.out.println(leadingText + ": " + getDiff() + " " + getUnit());
	}

	protected abstract String getUnit();

	/**
	 * 
	 * @return Returns the difference in time from the start (or last restart) to now.
	 */
	public final long getDiff() {
		return now() - start;
	}

	/**
	 * 
	 * @return Returns the current time in the unit of this {@link StopWatch}.
	 */
	public abstract long now();
}
