服务器之家

服务器之家 > 正文

Java计时器StopWatch实现方法代码实例

时间:2020-07-07 13:29     来源/作者:BarryW

下面提供三种计时器的写法供大家参考,大家可以自行选择自己钟爱的使用。

写法一(Spring 包提供的计时器):

?
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
import java.text.NumberFormat;
import java.util.LinkedList;
import java.util.List;
 
/**
 * Simple stop watch, allowing for timing of a number of tasks,
 * exposing total running time and running time for each named task.
 *
 * <p>Conceals use of {@code System.currentTimeMillis()}, improving the
 * readability of application code and reducing the likelihood of calculation errors.
 *
 * <p>Note that this object is not designed to be thread-safe and does not
 * use synchronization.
 *
 * <p>This class is normally used to verify performance during proof-of-concepts
 * and in development, rather than as part of production applications.
 *
 * @author Rod Johnson
 * @author Juergen Hoeller
 * @author Sam Brannen
 * @since May 2, 2001
 */
public class StopWatch {
 
  /**
   * Identifier of this stop watch.
   * Handy when we have output from multiple stop watches
   * and need to distinguish between them in log or console output.
   */
  private final String id;
 
  private boolean keepTaskList = true;
 
  private final List<TaskInfo> taskList = new LinkedList<TaskInfo>();
 
  /** Start time of the current task */
  private long startTimeMillis;
 
  /** Is the stop watch currently running? */
  private boolean running;
 
  /** Name of the current task */
  private String currentTaskName;
 
  private TaskInfo lastTaskInfo;
 
  private int taskCount;
 
  /** Total running time */
  private long totalTimeMillis;
 
 
  /**
   * Construct a new stop watch. Does not start any task.
   */
  public StopWatch() {
    this("");
  }
 
  /**
   * Construct a new stop watch with the given id.
   * Does not start any task.
   * @param id identifier for this stop watch.
   * Handy when we have output from multiple stop watches
   * and need to distinguish between them.
   */
  public StopWatch(String id) {
    this.id = id;
  }
 
 
  /**
   * Return the id of this stop watch, as specified on construction.
   * @return the id (empty String by default)
   * @since 4.2.2
   * @see #StopWatch(String)
   */
  public String getId() {
    return this.id;
  }
 
  /**
   * Determine whether the TaskInfo array is built over time. Set this to
   * "false" when using a StopWatch for millions of intervals, or the task
   * info structure will consume excessive memory. Default is "true".
   */
  public void setKeepTaskList(boolean keepTaskList) {
    this.keepTaskList = keepTaskList;
  }
 
 
  /**
   * Start an unnamed task. The results are undefined if {@link #stop()}
   * or timing methods are called without invoking this method.
   * @see #stop()
   */
  public void start() throws IllegalStateException {
    start("");
  }
 
  /**
   * Start a named task. The results are undefined if {@link #stop()}
   * or timing methods are called without invoking this method.
   * @param taskName the name of the task to start
   * @see #stop()
   */
  public void start(String taskName) throws IllegalStateException {
    if (this.running) {
      throw new IllegalStateException("Can't start StopWatch: it's already running");
    }
    this.running = true;
    this.currentTaskName = taskName;
    this.startTimeMillis = System.currentTimeMillis();
  }
 
  /**
   * Stop the current task. The results are undefined if timing
   * methods are called without invoking at least one pair
   * {@code start()} / {@code stop()} methods.
   * @see #start()
   */
  public void stop() throws IllegalStateException {
    if (!this.running) {
      throw new IllegalStateException("Can't stop StopWatch: it's not running");
    }
    long lastTime = System.currentTimeMillis() - this.startTimeMillis;
    this.totalTimeMillis += lastTime;
    this.lastTaskInfo = new TaskInfo(this.currentTaskName, lastTime);
    if (this.keepTaskList) {
      this.taskList.add(lastTaskInfo);
    }
    ++this.taskCount;
    this.running = false;
    this.currentTaskName = null;
  }
 
  /**
   * Return whether the stop watch is currently running.
   * @see #currentTaskName()
   */
  public boolean isRunning() {
    return this.running;
  }
 
  /**
   * Return the name of the currently running task, if any.
   * @since 4.2.2
   * @see #isRunning()
   */
  public String currentTaskName() {
    return this.currentTaskName;
  }
 
 
  /**
   * Return the time taken by the last task.
   */
  public long getLastTaskTimeMillis() throws IllegalStateException {
    if (this.lastTaskInfo == null) {
      throw new IllegalStateException("No tasks run: can't get last task interval");
    }
    return this.lastTaskInfo.getTimeMillis();
  }
 
  /**
   * Return the name of the last task.
   */
  public String getLastTaskName() throws IllegalStateException {
    if (this.lastTaskInfo == null) {
      throw new IllegalStateException("No tasks run: can't get last task name");
    }
    return this.lastTaskInfo.getTaskName();
  }
 
  /**
   * Return the last task as a TaskInfo object.
   */
  public TaskInfo getLastTaskInfo() throws IllegalStateException {
    if (this.lastTaskInfo == null) {
      throw new IllegalStateException("No tasks run: can't get last task info");
    }
    return this.lastTaskInfo;
  }
 
 
  /**
   * Return the total time in milliseconds for all tasks.
   */
  public long getTotalTimeMillis() {
    return this.totalTimeMillis;
  }
 
  /**
   * Return the total time in seconds for all tasks.
   */
  public double getTotalTimeSeconds() {
    return this.totalTimeMillis / 1000.0;
  }
 
  /**
   * Return the number of tasks timed.
   */
  public int getTaskCount() {
    return this.taskCount;
  }
 
  /**
   * Return an array of the data for tasks performed.
   */
  public TaskInfo[] getTaskInfo() {
    if (!this.keepTaskList) {
      throw new UnsupportedOperationException("Task info is not being kept!");
    }
    return this.taskList.toArray(new TaskInfo[this.taskList.size()]);
  }
 
 
  /**
   * Return a short description of the total running time.
   */
  public String shortSummary() {
    return "StopWatch '" + getId() + "': running time (millis) = " + getTotalTimeMillis();
  }
 
  /**
   * Return a string with a table describing all tasks performed.
   * For custom reporting, call getTaskInfo() and use the task info directly.
   */
  public String prettyPrint() {
    StringBuilder sb = new StringBuilder(shortSummary());
    sb.append('\n');
    if (!this.keepTaskList) {
      sb.append("No task info kept");
    }
    else {
      sb.append("-----------------------------------------\n");
      sb.append("ms   %   Task name\n");
      sb.append("-----------------------------------------\n");
      NumberFormat nf = NumberFormat.getNumberInstance();
      nf.setMinimumIntegerDigits(5);
      nf.setGroupingUsed(false);
      NumberFormat pf = NumberFormat.getPercentInstance();
      pf.setMinimumIntegerDigits(3);
      pf.setGroupingUsed(false);
      for (TaskInfo task : getTaskInfo()) {
        sb.append(nf.format(task.getTimeMillis())).append(" ");
        sb.append(pf.format(task.getTimeSeconds() / getTotalTimeSeconds())).append(" ");
        sb.append(task.getTaskName()).append("\n");
      }
    }
    return sb.toString();
  }
 
  /**
   * Return an informative string describing all tasks performed
   * For custom reporting, call {@code getTaskInfo()} and use the task info directly.
   */
  @Override
  public String toString() {
    StringBuilder sb = new StringBuilder(shortSummary());
    if (this.keepTaskList) {
      for (TaskInfo task : getTaskInfo()) {
        sb.append("; [").append(task.getTaskName()).append("] took ").append(task.getTimeMillis());
        long percent = Math.round((100.0 * task.getTimeSeconds()) / getTotalTimeSeconds());
        sb.append(" = ").append(percent).append("%");
      }
    }
    else {
      sb.append("; no task info kept");
    }
    return sb.toString();
  }
 
 
  /**
   * Inner class to hold data about one task executed within the stop watch.
   */
  public static final class TaskInfo {
 
    private final String taskName;
 
    private final long timeMillis;
 
    TaskInfo(String taskName, long timeMillis) {
      this.taskName = taskName;
      this.timeMillis = timeMillis;
    }
 
    /**
     * Return the name of this task.
     */
    public String getTaskName() {
      return this.taskName;
    }
 
    /**
     * Return the time in milliseconds this task took.
     */
    public long getTimeMillis() {
      return this.timeMillis;
    }
 
    /**
     * Return the time in seconds this task took.
     */
    public double getTimeSeconds() {
      return (this.timeMillis / 1000.0);
    }
  }
 
}

下面写一个调用:

?
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
public static void main(String[] args) throws InterruptedException {
//    StopWatchTest.test0();
   StopWatchTest.test1();
}
 
public static void test1() throws InterruptedException {
   StopWatch sw = new StopWatch("test");
   sw.start("task1");
   // do something
  Thread.sleep(100);
  sw.stop();
  sw.start("task2");
  // do something
  Thread.sleep(200);
  sw.stop();
  System.out.println("sw.prettyPrint()~~~~~~~~~~~~~~~~~");
  System.out.println(sw.prettyPrint());
}

运行结果:

sw.prettyPrint()~~~~~~~~~~~~~~~~~
StopWatch 'test': running time (millis) = 308
-----------------------------------------
ms % Task name
-----------------------------------------
00104 034% task1
00204 066% task2
---------------------

start开始记录,stop停止记录,然后通过StopWatch的prettyPrint方法,可直观的输出代码执行耗时,以及执行时间百分比,瞬间感觉比之前的方式高大上了一个档次。

 除此之外,还有以下两个方法shortSummary,getTotalTimeMillis,查看程序执行时间。

写法二(apache.commons实现的计时器):

?
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
import java.util.concurrent.TimeUnit;
 
/**
 * <p>
 * <code>StopWatch</code> provides a convenient API for timings.
 * </p>
 *
 * <p>
 * To start the watch, call {@link #start()} or {@link StopWatch#createStarted()}. 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>
 *
 * <p>
 * NOTE: As from v2.1, the methods protect against inappropriate calls. Thus you cannot now call stop before start,
 * resume before suspend or unsplit before split.
 * </p>
 *
 * <p>
 * 1. split(), suspend(), or stop() cannot be invoked twice<br>
 * 2. unsplit() may only be called if the watch has been split()<br>
 * 3. resume() may only be called if the watch has been suspend()<br>
 * 4. start() cannot be called twice without calling reset()
 * </p>
 *
 * <p>This class is not thread-safe</p>
 *
 * @since 2.0
 */
public class StopWatch {
 
  private static final long NANO_2_MILLIS = 1000000L;
 
 
  /**
   * Provides a started stopwatch for convenience.
   *
   * @return StopWatch a stopwatch that's already been started.
   *
   * @since 3.5
   */
  public static StopWatch createStarted() {
    final StopWatch sw = new StopWatch();
    sw.start();
    return sw;
  }
 
  /**
   * Enumeration type which indicates the status of stopwatch.
   */
  private enum State {
 
    UNSTARTED {
      @Override
      boolean isStarted() {
        return false;
      }
      @Override
      boolean isStopped() {
        return true;
      }
      @Override
      boolean isSuspended() {
        return false;
      }
    },
    RUNNING {
      @Override
      boolean isStarted() {
        return true;
      }
      @Override
      boolean isStopped() {
        return false;
      }
      @Override
      boolean isSuspended() {
        return false;
      }
    },
    STOPPED {
      @Override
      boolean isStarted() {
        return false;
      }
      @Override
      boolean isStopped() {
        return true;
      }
      @Override
      boolean isSuspended() {
        return false;
      }
    },
    SUSPENDED {
      @Override
      boolean isStarted() {
        return true;
      }
      @Override
      boolean isStopped() {
        return false;
      }
      @Override
      boolean isSuspended() {
        return true;
      }
    };
 
    /**
     * <p>
     * The method is used to find out if the StopWatch is started. A suspended
     * StopWatch is also started watch.
     * </p>
 
     * @return boolean
     *       If the StopWatch is started.
     */
    abstract boolean isStarted();
 
    /**
     * <p>
     * This method is used to find out whether the StopWatch is stopped. The
     * stopwatch which's not yet started and explicitly stopped stopwatch is
     * considered as stopped.
     * </p>
     *
     * @return boolean
     *       If the StopWatch is stopped.
     */
    abstract boolean isStopped();
 
    /**
     * <p>
     * This method is used to find out whether the StopWatch is suspended.
     * </p>
     *
     * @return boolean
     *       If the StopWatch is suspended.
     */
    abstract boolean isSuspended();
  }
 
  /**
   * Enumeration type which indicates the split status of stopwatch.
   */
  private enum SplitState {
    SPLIT,
    UNSPLIT
  }
  /**
   * The current running state of the StopWatch.
   */
  private State runningState = State.UNSTARTED;
 
  /**
   * Whether the stopwatch has a split time recorded.
   */
  private SplitState splitState = SplitState.UNSPLIT;
 
  /**
   * The start time.
   */
  private long startTime;
 
  /**
   * The start time in Millis - nanoTime is only for elapsed time so we
   * need to also store the currentTimeMillis to maintain the old
   * getStartTime API.
   */
  private long startTimeMillis;
 
  /**
   * The stop time.
   */
  private long stopTime;
 
  /**
   * <p>
   * Constructor.
   * </p>
   */
  public StopWatch() {
    super();
  }
 
  /**
   * <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. ");
    }
    this.startTime = System.nanoTime();
    this.startTimeMillis = 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. ");
    }
    if (this.runningState == State.RUNNING) {
      this.stopTime = System.nanoTime();
    }
    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 = SplitState.UNSPLIT;
  }
 
  /**
   * <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. ");
    }
    this.stopTime = System.nanoTime();
    this.splitState = SplitState.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 != SplitState.SPLIT) {
      throw new IllegalStateException("Stopwatch has not been split. ");
    }
    this.splitState = SplitState.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. ");
    }
    this.stopTime = System.nanoTime();
    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. ");
    }
    this.startTime += System.nanoTime() - this.stopTime;
    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() {
    return getNanoTime() / NANO_2_MILLIS;
  }
 
  /**
   * <p>
   * Get the time on the stopwatch in the specified TimeUnit.
   * </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. The resulting time will be expressed in the desired TimeUnit with any remainder rounded down.
   * For example, if the specified unit is {@code TimeUnit.HOURS} and the stopwatch time is 59 minutes, then the
   * result returned will be {@code 0}.
   * </p>
   *
   * @param timeUnit the unit of time, not null
   * @return the time in the specified TimeUnit, rounded down
   * @since 3.5
   */
  public long getTime(final TimeUnit timeUnit) {
    return timeUnit.convert(getNanoTime(), TimeUnit.NANOSECONDS);
  }
 
  /**
   * <p>
   * Get the time on the stopwatch in nanoseconds.
   * </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 nanoseconds
   * @since 3.0
   */
  public long getNanoTime() {
    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.nanoTime() - this.startTime;
    }
    throw new RuntimeException("Illegal running state has occurred.");
  }
 
  /**
   * <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.
   * @since 2.1
   */
  public long getSplitTime() {
    return getSplitNanoTime() / NANO_2_MILLIS;
  }
  /**
   * <p>
   * Get the split time on the stopwatch in nanoseconds.
   * </p>
   *
   * <p>
   * This is the time between start and latest split.
   * </p>
   *
   * @return the split time in nanoseconds
   *
   * @throws IllegalStateException
   *       if the StopWatch has not yet been split.
   * @since 3.0
   */
  public long getSplitNanoTime() {
    if (this.splitState != SplitState.SPLIT) {
      throw new IllegalStateException("Stopwatch must be split to get the split time. ");
    }
    return this.stopTime - this.startTime;
  }
 
  /**
   * Returns the time this stopwatch was started.
   *
   * @return the time this stopwatch was started
   * @throws IllegalStateException
   *       if this StopWatch has not been started
   * @since 2.4
   */
  public long getStartTime() {
    if (this.runningState == State.UNSTARTED) {
      throw new IllegalStateException("Stopwatch has not been started");
    }
    // System.nanoTime is for elapsed time
    return this.startTimeMillis;
  }
 
  /**
   * <p>
   * Gets a summary of the time that the stopwatch recorded as a string.
   * </p>
   *
   * <p>
   * The format used is ISO 8601-like, <i>hours</i>:<i>minutes</i>:<i>seconds</i>.<i>milliseconds</i>.
   * </p>
   *
   * @return the time as a String
   */
  @Override
  public String toString() {
    return DurationFormatUtils.formatDurationHMS(getTime());
  }
 
  /**
   * <p>
   * Gets a summary of the split time that the stopwatch recorded as a string.
   * </p>
   *
   * <p>
   * The format used is ISO 8601-like, <i>hours</i>:<i>minutes</i>:<i>seconds</i>.<i>milliseconds</i>.
   * </p>
   *
   * @return the split time as a String
   * @since 2.1
   */
  public String toSplitString() {
    return DurationFormatUtils.formatDurationHMS(getSplitTime());
  }
 
  /**
   * <p>
   * The method is used to find out if the StopWatch is started. A suspended
   * StopWatch is also started watch.
   * </p>
   *
   * @return boolean
   *       If the StopWatch is started.
   * @since 3.2
   */
  public boolean isStarted() {
    return runningState.isStarted();
  }
 
  /**
   * <p>
   * This method is used to find out whether the StopWatch is suspended.
   * </p>
   *
   * @return boolean
   *       If the StopWatch is suspended.
   * @since 3.2
   */
  public boolean isSuspended() {
    return runningState.isSuspended();
  }
 
  /**
   * <p>
   * This method is used to find out whether the StopWatch is stopped. The
   * stopwatch which's not yet started and explicitly stopped stopwatch is
   * considered as stopped.
   * </p>
   *
   * @return boolean
   *       If the StopWatch is stopped.
   * @since 3.2
   */
  public boolean isStopped() {
    return runningState.isStopped();
  }
 
}

写法三(Scala函数写法):

?
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
import org.slf4j.LoggerFactory
 
/**
 * 类功能描述:Debug日志追踪
 *
 * @author barry create at 18-8-29 下午3:41
 * @version 1.0.0
 */
object Debug {
 val LOGGER = LoggerFactory.getLogger(getClass)
 val counter = collection.mutable.Map[String, Int]() // label -> count
 val times = collection.mutable.Map[String, Long]() // label - time(ns)
 
 /**
  *追踪代码块
  * @param label 标签名
  * @param codeBlock 代码块
  * @tparam T 返回结果类型
  * @return
  */
 def trace[T](label: String)(codeBlock: => T) = {
  val t0 = System.nanoTime()
  val result = codeBlock
  val t1 = System.nanoTime()
  counter.get(label).map(_counter => counter.put(label, _counter + 1)).orElse(counter.put(label, 1))
  times.get(label).map(cost => times.put(label, cost + (t1 - t0))).orElse(times.put(label, t1 - t0))
  result
 }
 
 /**
  * 打印日志
  */
 def info(): Unit = {
  LOGGER.warn("FinallyDone...")
  LOGGER.warn(s"counter:${counter}")
  LOGGER.warn(s"times:${times.map { case (label, cost) => (label, cost / 1000000)}}ms")
 }
 
 /**
  * 重新计数
  */
 def reset(): Unit = {
  counter.clear()
  times.clear()
 }
}

参考下面测试代码:

java版本:

?
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
/**
 * @author WangXueXing create at 19-7-31 下午1:46
 * @version 1.0.0
 */
public class StopWatchDemo {
  public static void main(String[] args){
    Debug.trace("方法1调用次数及用时", ()->{
      try {
        Thread.sleep(2000);
      } catch (InterruptedException e) {
        e.printStackTrace();
      }
      return "";
    });
 
    Debug.trace("方法1调用次数及用时", ()->{
      try {
        Thread.sleep(2000);
      } catch (InterruptedException e) {
        e.printStackTrace();
      }
      return "";
    });
 
    Debug.trace("方法2调用次数及用时", ()->{
      try {
        Thread.sleep(2000);
      } catch (InterruptedException e) {
        e.printStackTrace();
      }
      return 10;
    });
 
    Debug.info();
  }
}

输出结果:

15:29:32.228 [main] WARN test.Debug$ - FinallyDone...
15:29:32.361 [main] WARN test.Debug$ - counter:Map(方法2调用次数及用时 -> 1, 方法1调用次数及用时 -> 2)
15:29:32.364 [main] WARN test.Debug$ - times:Map(方法2调用次数及用时 -> 2000, 方法1调用次数及用时 -> 4000)ms

scala版本:

?
1
2
3
4
5
6
7
8
9
10
11
12
/**
 * @author WangXueXing create at 19-8-1 下午3:40
 * @version 1.0.0
 */
object StopWatchTest {
 def main(args: Array[String]): Unit = {
  Debug.trace("方法1调用次数及用时")( Thread.sleep(200))
  Debug.trace("方法1调用次数及用时")( Thread.sleep(200))
  Debug.trace("方法2调用次数及用时")( Thread.sleep(200))
  Debug.info()
 }
}

输出结果:

15:43:58.601 [main] WARN test.stopwatch.Debug$ - FinallyDone...
15:43:58.735 [main] WARN test.stopwatch.Debug$ - counter:Map(方法2调用次数及用时 -> 1, 方法1调用次数及用时 -> 2)
15:43:58.739 [main] WARN test.stopwatch.Debug$ - times:Map(方法2调用次数及用时 -> 200, 方法1调用次数及用时 -> 400)ms

对比java版本与scala版本,是不是看到scala的简洁及强大了吧!

以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持服务器之家。

原文链接:https://www.cnblogs.com/barrywxx/p/11282215.html

标签:

相关文章

热门资讯

2020微信伤感网名听哭了 让对方看到心疼的伤感网名大全
2020微信伤感网名听哭了 让对方看到心疼的伤感网名大全 2019-12-26
歪歪漫画vip账号共享2020_yy漫画免费账号密码共享
歪歪漫画vip账号共享2020_yy漫画免费账号密码共享 2020-04-07
沙雕群名称大全2019精选 今年最火的微信群名沙雕有创意
沙雕群名称大全2019精选 今年最火的微信群名沙雕有创意 2019-07-07
男生常说24816是什么意思?女生说13579是什么意思?
男生常说24816是什么意思?女生说13579是什么意思? 2019-09-17
玄元剑仙肉身有什么用 玄元剑仙肉身境界等级划分
玄元剑仙肉身有什么用 玄元剑仙肉身境界等级划分 2019-06-21
返回顶部