| /* |
| * Copyright 2002-2004 The Apache Software Foundation. |
| * |
| * 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 org.apache.commons.lang.time; |
| |
| /** |
| * <p><code>StopWatch</code> provides a convenient API for timings.</p> |
| * |
| * <p>The methods do <b>not</b> protect against inappropriate calls. Thus you |
| * can call stop before start, resume before suspend or unsplit before split. |
| * The results are indeterminate in these cases.</p> |
| * |
| * <p>To start the watch, call {@link #start()}. At this point you can:</p> |
| * <ul> |
| * <li>{@link #split()} the watch to get the time whilst the watch continues in the |
| * background. {@link #unsplit()} will remove the effect of the split. At this point, |
| * these three options are available again.</li> |
| * <li>{@link #suspend()} the watch to pause it. {@link #resume()} allows the watch |
| * to continue. Any time between the suspend and resume will not be counted in |
| * the total. At this point, these three options are available again.</li> |
| * <li>{@link #stop()} the watch to complete the timing session.</li> |
| * </ul> |
| * |
| * <p>It is intended that the output methods {@link #toString()} and {@link #getTime()} |
| * should only be called after stop, split or suspend, however a suitable result will |
| * be returned at other points.</p> |
| |
| 1. split(), suspend(), or stop() cannot be invoked twice. |
| 2. unsplit() may only be called if the watch has been split() |
| 3. resume() may only be called if the watch has been suspend() |
| 4. start() cannot be called twice. |
| |
| * |
| * @author Henri Yandell |
| * @author Stephen Colebourne |
| * @since 2.0 |
| * @version $Id: StopWatch.java,v 1.9 2004/07/25 07:31:36 bayard Exp $ |
| */ |
| public class StopWatch { |
| |
| // running states |
| private static final int STATE_UNSTARTED = 0; |
| private static final int STATE_RUNNING = 1; |
| private static final int STATE_STOPPED = 2; |
| private static final int STATE_SUSPENDED = 3; |
| |
| // split state |
| private static final int STATE_UNSPLIT = 10; |
| private static final int STATE_SPLIT = 11; |
| |
| /** |
| * The current running state of the StopWatch. |
| */ |
| private int runningState = STATE_UNSTARTED; |
| |
| /** |
| * Whether the stopwatch has a split time recorded. |
| */ |
| private int splitState = STATE_UNSPLIT; |
| |
| /** |
| * The start time. |
| */ |
| private long startTime = -1; |
| /** |
| * The stop time. |
| */ |
| private long stopTime = -1; |
| |
| /** |
| * <p>Constructor.</p> |
| */ |
| public StopWatch() { |
| } |
| |
| /** |
| * <p>Start the stopwatch.</p> |
| * |
| * <p>This method starts a new timing session, clearing any previous values.</p> |
| * |
| * @throws IllegalStateException if the StopWatch is already running. |
| */ |
| public void start() { |
| if(this.runningState == STATE_STOPPED) { |
| throw new IllegalStateException("Stopwatch must be reset before being restarted. "); |
| } |
| if(this.runningState != STATE_UNSTARTED) { |
| throw new IllegalStateException("Stopwatch already started. "); |
| } |
| stopTime = -1; |
| startTime = System.currentTimeMillis(); |
| this.runningState = STATE_RUNNING; |
| } |
| |
| /** |
| * <p>Stop the stopwatch.</p> |
| * |
| * <p>This method ends a new timing session, allowing the time to be retrieved.</p> |
| * |
| * @throws IllegalStateException if the StopWatch is not running. |
| */ |
| public void stop() { |
| if(this.runningState != STATE_RUNNING && this.runningState != STATE_SUSPENDED) { |
| throw new IllegalStateException("Stopwatch is not running. "); |
| } |
| stopTime = System.currentTimeMillis(); |
| this.runningState = STATE_STOPPED; |
| } |
| |
| /** |
| * <p>Resets the stopwatch. Stops it if need be. </p> |
| * |
| * <p>This method clears the internal values to allow the object to be reused.</p> |
| */ |
| public void reset() { |
| this.runningState = STATE_UNSTARTED; |
| this.splitState = STATE_UNSPLIT; |
| startTime = -1; |
| stopTime = -1; |
| } |
| |
| /** |
| * <p>Split the time.</p> |
| * |
| * <p>This method sets the stop time of the watch to allow a time to be extracted. |
| * The start time is unaffected, enabling {@link #unsplit()} to continue the |
| * timing from the original start point.</p> |
| * |
| * @throws IllegalStateException if the StopWatch is not running. |
| */ |
| public void split() { |
| if(this.runningState != STATE_RUNNING) { |
| throw new IllegalStateException("Stopwatch is not running. "); |
| } |
| stopTime = System.currentTimeMillis(); |
| this.splitState = STATE_SPLIT; |
| } |
| |
| /** |
| * <p>Remove a split.</p> |
| * |
| * <p>This method clears the stop time. The start time is unaffected, enabling |
| * timing from the original start point to continue.</p> |
| * |
| * @throws IllegalStateException if the StopWatch has not been split. |
| */ |
| public void unsplit() { |
| if(this.splitState != STATE_SPLIT) { |
| throw new IllegalStateException("Stopwatch has not been split. "); |
| } |
| stopTime = -1; |
| this.splitState = STATE_UNSPLIT; |
| } |
| |
| /** |
| * <p>Suspend the stopwatch for later resumption.</p> |
| * |
| * <p>This method suspends the watch until it is resumed. The watch will not include |
| * time between the suspend and resume calls in the total time.</p> |
| * |
| * @throws IllegalStateException if the StopWatch is not currently running. |
| */ |
| public void suspend() { |
| if(this.runningState != STATE_RUNNING) { |
| throw new IllegalStateException("Stopwatch must be running to suspend. "); |
| } |
| stopTime = System.currentTimeMillis(); |
| this.runningState = STATE_SUSPENDED; |
| } |
| |
| /** |
| * <p>Resume the stopwatch after a suspend.</p> |
| * |
| * <p>This method resumes the watch after it was suspended. The watch will not include |
| * time between the suspend and resume calls in the total time.</p> |
| * |
| * @throws IllegalStateException if the StopWatch has not been suspended. |
| */ |
| public void resume() { |
| if(this.runningState != STATE_SUSPENDED) { |
| throw new IllegalStateException("Stopwatch must be suspended to resume. "); |
| } |
| startTime += (System.currentTimeMillis() - stopTime); |
| stopTime = -1; |
| this.runningState = STATE_RUNNING; |
| } |
| |
| /** |
| * <p>Get the time on the stopwatch.</p> |
| * |
| * <p>This is either the time between the start and the moment this method |
| * is called, or the amount of time between start and stop.</p> |
| * |
| * @return the time in milliseconds |
| */ |
| public long getTime() { |
| if(this.runningState == STATE_STOPPED || this.runningState == STATE_SUSPENDED) { |
| return (this.stopTime - this.startTime); |
| } else |
| if(this.runningState == STATE_UNSTARTED) { |
| return 0; |
| } else |
| if(this.runningState == STATE_RUNNING) { |
| return (System.currentTimeMillis() - this.startTime); |
| } |
| throw new RuntimeException("Illegal running state has occured. "); |
| } |
| |
| /** |
| * <p>Get the split time on the stopwatch.</p> |
| * |
| * <p>This is the time between start and latest split. </p> |
| * |
| * @return the split time in milliseconds |
| * |
| * @throws IllegalStateException if the StopWatch has not yet been split. |
| */ |
| public long getSplitTime() { |
| if(this.splitState != STATE_SPLIT) { |
| throw new IllegalStateException("Stopwatch must be split to get the split time. "); |
| } |
| return (this.stopTime - this.startTime); |
| } |
| |
| /** |
| * <p>Gets a summary of the time that the stopwatch recorded as a string.</p> |
| * |
| * <p>The format used is ISO8601-like, |
| * <i>hours</i>:<i>minutes</i>:<i>seconds</i>.<i>milliseconds</i>.</p> |
| * |
| * @return the time as a String |
| */ |
| public String toString() { |
| return DurationFormatUtils.formatISO(getTime()); |
| } |
| |
| /** |
| * <p>Gets a summary of the split time that the stopwatch recorded as a string.</p> |
| * |
| * <p>The format used is ISO8601-like, |
| * <i>hours</i>:<i>minutes</i>:<i>seconds</i>.<i>milliseconds</i>.</p> |
| * |
| * @return the split time as a String |
| */ |
| public String toSplitString() { |
| return DurationFormatUtils.formatISO(getSplitTime()); |
| } |
| |
| } |