source: trunk/src/org/expeditee/gui/TimeKeeper.java@ 1428

/**
 *    TimeKeeper.java
 *    Copyright (C) 2010 New Zealand Digital Library, http://expeditee.org
 *
 *    This program is free software: you can redistribute it and/or modify
 *    it under the terms of the GNU General Public License as published by
 *    the Free Software Foundation, either version 3 of the License, or
 *    (at your option) any later version.
 *
 *    This program is distributed in the hope that it will be useful,
 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *    GNU General Public License for more details.
 *
 *    You should have received a copy of the GNU General Public License
 *    along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

package org.expeditee.gui;

import java.text.DecimalFormat;

/**
 * Provides methods an easy way of measuring time. Currently uses
 * System.nanoTime to get the most precise time measurement available, results
 * are then converted to milliseconds.
 * 
 * @author jdm18
 */
public class TimeKeeper {

        /**
         * The Unit of measure for the returned time values
         */
        public static DecimalFormat Formatter = new DecimalFormat("0.00");

        private long _start = 0;

        private static String MILLIS = "ms";

        private static String SECONDS = "sec";

        /**
         * Constructs a new TimeKeeper object and initiates the starting time
         */
        public TimeKeeper() {
                restart();
        }

        /**
         * Returns the time Sandbox has been running, in the time unit set in UNIT.
         * 
         * @return The amount of time Sandbox has been running.
         */
        public static long getCurrentTime() {
                long nanoTime = System.nanoTime();

                nanoTime /= 1000000;

                return nanoTime;
        }

        /**
         * Resets the starting time of this TimeKeeper to the value returned by
         * getCurrentTime()
         */
        public void restart() {
                _start = getCurrentTime();
        }

        /**
         * Returns the difference between the current time (getCurrentTime()) and
         * this TimeKeeper's starting time.
         * 
         * @return The time that has elapsed since this TimeKeeper's start time.
         */
        public long getElapsedMillis() {
                return getCurrentTime() - _start;
        }

        /**
         * The same result as getElapsed() but with the unit of measure (UNIT)
         * appended.
         * 
         * @return The time that has elapsed since this TimeKeeper's start time,
         *         with the unit of measure displayed.
         */
        public String getElapsedStringMillis() {
                return getElapsedMillis() + MILLIS;
        }

        public String getElapsedStringMillis(int pad) {
                long time = getElapsedMillis();
                String padding = "";
                for (int i = 0; i < pad; i++)
                        if (time == 0)
                                padding += " ";
                        else
                                time /= 10;

                return padding + getElapsedMillis() + MILLIS;
        }

        // returns the string in mm:ss format, with seconds shown to 3 decimal
        // places
        public String getElapsedStringFull() {
                int mins = (int) Math.floor(getElapsedSeconds() / 60f);
                float secs = getElapsedSeconds() - (mins * 60);

                return mins + ":" + Formatter.format(secs);
        }

        public String getElapsedStringSeconds() {
                return Formatter.format(getElapsedSeconds()) + SECONDS;
        }

        public float getElapsedSeconds() {
                return getElapsedMillis() / 1000f;
        }
}