-
Notifications
You must be signed in to change notification settings - Fork 420
/
picocli-2.0-groovy-scripts-on-steroids.html
893 lines (872 loc) · 56.6 KB
/
picocli-2.0-groovy-scripts-on-steroids.html
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
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta name="generator" content="Asciidoctor 2.0.18">
<title>Picocli 2.0: Groovy Scripts on Steroids</title>
<link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans:300,300italic,400,400italic,600,600italic%7CNoto+Serif:400,400italic,700,700italic%7CDroid+Sans+Mono:400,700">
<style>
/*! Asciidoctor default stylesheet | MIT License | https://asciidoctor.org */
/* Uncomment the following line when using as a custom stylesheet */
/* @import "https://fonts.googleapis.com/css?family=Open+Sans:300,300italic,400,400italic,600,600italic%7CNoto+Serif:400,400italic,700,700italic%7CDroid+Sans+Mono:400,700"; */
html{font-family:sans-serif;-webkit-text-size-adjust:100%}
a{background:none}
a:focus{outline:thin dotted}
a:active,a:hover{outline:0}
h1{font-size:2em;margin:.67em 0}
b,strong{font-weight:bold}
abbr{font-size:.9em}
abbr[title]{cursor:help;border-bottom:1px dotted #dddddf;text-decoration:none}
dfn{font-style:italic}
hr{height:0}
mark{background:#ff0;color:#000}
code,kbd,pre,samp{font-family:monospace;font-size:1em}
pre{white-space:pre-wrap}
q{quotes:"\201C" "\201D" "\2018" "\2019"}
small{font-size:80%}
sub,sup{font-size:75%;line-height:0;position:relative;vertical-align:baseline}
sup{top:-.5em}
sub{bottom:-.25em}
img{border:0}
svg:not(:root){overflow:hidden}
figure{margin:0}
audio,video{display:inline-block}
audio:not([controls]){display:none;height:0}
fieldset{border:1px solid silver;margin:0 2px;padding:.35em .625em .75em}
legend{border:0;padding:0}
button,input,select,textarea{font-family:inherit;font-size:100%;margin:0}
button,input{line-height:normal}
button,select{text-transform:none}
button,html input[type=button],input[type=reset],input[type=submit]{-webkit-appearance:button;cursor:pointer}
button[disabled],html input[disabled]{cursor:default}
input[type=checkbox],input[type=radio]{padding:0}
button::-moz-focus-inner,input::-moz-focus-inner{border:0;padding:0}
textarea{overflow:auto;vertical-align:top}
table{border-collapse:collapse;border-spacing:0}
*,::before,::after{box-sizing:border-box}
html,body{font-size:100%}
body{background:#fff;color:rgba(0,0,0,.8);padding:0;margin:0;font-family:"Noto Serif","DejaVu Serif",serif;line-height:1;position:relative;cursor:auto;-moz-tab-size:4;-o-tab-size:4;tab-size:4;word-wrap:anywhere;-moz-osx-font-smoothing:grayscale;-webkit-font-smoothing:antialiased}
a:hover{cursor:pointer}
img,object,embed{max-width:100%;height:auto}
object,embed{height:100%}
img{-ms-interpolation-mode:bicubic}
.left{float:left!important}
.right{float:right!important}
.text-left{text-align:left!important}
.text-right{text-align:right!important}
.text-center{text-align:center!important}
.text-justify{text-align:justify!important}
.hide{display:none}
img,object,svg{display:inline-block;vertical-align:middle}
textarea{height:auto;min-height:50px}
select{width:100%}
.subheader,.admonitionblock td.content>.title,.audioblock>.title,.exampleblock>.title,.imageblock>.title,.listingblock>.title,.literalblock>.title,.stemblock>.title,.openblock>.title,.paragraph>.title,.quoteblock>.title,table.tableblock>.title,.verseblock>.title,.videoblock>.title,.dlist>.title,.olist>.title,.ulist>.title,.qlist>.title,.hdlist>.title{line-height:1.45;color:#7a2518;font-weight:400;margin-top:0;margin-bottom:.25em}
div,dl,dt,dd,ul,ol,li,h1,h2,h3,#toctitle,.sidebarblock>.content>.title,h4,h5,h6,pre,form,p,blockquote,th,td{margin:0;padding:0}
a{color:#2156a5;text-decoration:underline;line-height:inherit}
a:hover,a:focus{color:#1d4b8f}
a img{border:0}
p{line-height:1.6;margin-bottom:1.25em;text-rendering:optimizeLegibility}
p aside{font-size:.875em;line-height:1.35;font-style:italic}
h1,h2,h3,#toctitle,.sidebarblock>.content>.title,h4,h5,h6{font-family:"Open Sans","DejaVu Sans",sans-serif;font-weight:300;font-style:normal;color:#ba3925;text-rendering:optimizeLegibility;margin-top:1em;margin-bottom:.5em;line-height:1.0125em}
h1 small,h2 small,h3 small,#toctitle small,.sidebarblock>.content>.title small,h4 small,h5 small,h6 small{font-size:60%;color:#e99b8f;line-height:0}
h1{font-size:2.125em}
h2{font-size:1.6875em}
h3,#toctitle,.sidebarblock>.content>.title{font-size:1.375em}
h4,h5{font-size:1.125em}
h6{font-size:1em}
hr{border:solid #dddddf;border-width:1px 0 0;clear:both;margin:1.25em 0 1.1875em}
em,i{font-style:italic;line-height:inherit}
strong,b{font-weight:bold;line-height:inherit}
small{font-size:60%;line-height:inherit}
code{font-family:"Droid Sans Mono","DejaVu Sans Mono",monospace;font-weight:400;color:rgba(0,0,0,.9)}
ul,ol,dl{line-height:1.6;margin-bottom:1.25em;list-style-position:outside;font-family:inherit}
ul,ol{margin-left:1.5em}
ul li ul,ul li ol{margin-left:1.25em;margin-bottom:0}
ul.circle{list-style-type:circle}
ul.disc{list-style-type:disc}
ul.square{list-style-type:square}
ul.circle ul:not([class]),ul.disc ul:not([class]),ul.square ul:not([class]){list-style:inherit}
ol li ul,ol li ol{margin-left:1.25em;margin-bottom:0}
dl dt{margin-bottom:.3125em;font-weight:bold}
dl dd{margin-bottom:1.25em}
blockquote{margin:0 0 1.25em;padding:.5625em 1.25em 0 1.1875em;border-left:1px solid #ddd}
blockquote,blockquote p{line-height:1.6;color:rgba(0,0,0,.85)}
@media screen and (min-width:768px){h1,h2,h3,#toctitle,.sidebarblock>.content>.title,h4,h5,h6{line-height:1.2}
h1{font-size:2.75em}
h2{font-size:2.3125em}
h3,#toctitle,.sidebarblock>.content>.title{font-size:1.6875em}
h4{font-size:1.4375em}}
table{background:#fff;margin-bottom:1.25em;border:1px solid #dedede;word-wrap:normal}
table thead,table tfoot{background:#f7f8f7}
table thead tr th,table thead tr td,table tfoot tr th,table tfoot tr td{padding:.5em .625em .625em;font-size:inherit;color:rgba(0,0,0,.8);text-align:left}
table tr th,table tr td{padding:.5625em .625em;font-size:inherit;color:rgba(0,0,0,.8)}
table tr.even,table tr.alt{background:#f8f8f7}
table thead tr th,table tfoot tr th,table tbody tr td,table tr td,table tfoot tr td{line-height:1.6}
h1,h2,h3,#toctitle,.sidebarblock>.content>.title,h4,h5,h6{line-height:1.2;word-spacing:-.05em}
h1 strong,h2 strong,h3 strong,#toctitle strong,.sidebarblock>.content>.title strong,h4 strong,h5 strong,h6 strong{font-weight:400}
.center{margin-left:auto;margin-right:auto}
.stretch{width:100%}
.clearfix::before,.clearfix::after,.float-group::before,.float-group::after{content:" ";display:table}
.clearfix::after,.float-group::after{clear:both}
:not(pre).nobreak{word-wrap:normal}
:not(pre).nowrap{white-space:nowrap}
:not(pre).pre-wrap{white-space:pre-wrap}
:not(pre):not([class^=L])>code{font-size:.9375em;font-style:normal!important;letter-spacing:0;padding:.1em .5ex;word-spacing:-.15em;background:#f7f7f8;border-radius:4px;line-height:1.45;text-rendering:optimizeSpeed}
pre{color:rgba(0,0,0,.9);font-family:"Droid Sans Mono","DejaVu Sans Mono",monospace;line-height:1.45;text-rendering:optimizeSpeed}
pre code,pre pre{color:inherit;font-size:inherit;line-height:inherit}
pre>code{display:block}
pre.nowrap,pre.nowrap pre{white-space:pre;word-wrap:normal}
em em{font-style:normal}
strong strong{font-weight:400}
.keyseq{color:rgba(51,51,51,.8)}
kbd{font-family:"Droid Sans Mono","DejaVu Sans Mono",monospace;display:inline-block;color:rgba(0,0,0,.8);font-size:.65em;line-height:1.45;background:#f7f7f7;border:1px solid #ccc;border-radius:3px;box-shadow:0 1px 0 rgba(0,0,0,.2),inset 0 0 0 .1em #fff;margin:0 .15em;padding:.2em .5em;vertical-align:middle;position:relative;top:-.1em;white-space:nowrap}
.keyseq kbd:first-child{margin-left:0}
.keyseq kbd:last-child{margin-right:0}
.menuseq,.menuref{color:#000}
.menuseq b:not(.caret),.menuref{font-weight:inherit}
.menuseq{word-spacing:-.02em}
.menuseq b.caret{font-size:1.25em;line-height:.8}
.menuseq i.caret{font-weight:bold;text-align:center;width:.45em}
b.button::before,b.button::after{position:relative;top:-1px;font-weight:400}
b.button::before{content:"[";padding:0 3px 0 2px}
b.button::after{content:"]";padding:0 2px 0 3px}
p a>code:hover{color:rgba(0,0,0,.9)}
#header,#content,#footnotes,#footer{width:100%;margin:0 auto;max-width:62.5em;*zoom:1;position:relative;padding-left:.9375em;padding-right:.9375em}
#header::before,#header::after,#content::before,#content::after,#footnotes::before,#footnotes::after,#footer::before,#footer::after{content:" ";display:table}
#header::after,#content::after,#footnotes::after,#footer::after{clear:both}
#content{margin-top:1.25em}
#content::before{content:none}
#header>h1:first-child{color:rgba(0,0,0,.85);margin-top:2.25rem;margin-bottom:0}
#header>h1:first-child+#toc{margin-top:8px;border-top:1px solid #dddddf}
#header>h1:only-child,body.toc2 #header>h1:nth-last-child(2){border-bottom:1px solid #dddddf;padding-bottom:8px}
#header .details{border-bottom:1px solid #dddddf;line-height:1.45;padding-top:.25em;padding-bottom:.25em;padding-left:.25em;color:rgba(0,0,0,.6);display:flex;flex-flow:row wrap}
#header .details span:first-child{margin-left:-.125em}
#header .details span.email a{color:rgba(0,0,0,.85)}
#header .details br{display:none}
#header .details br+span::before{content:"\00a0\2013\00a0"}
#header .details br+span.author::before{content:"\00a0\22c5\00a0";color:rgba(0,0,0,.85)}
#header .details br+span#revremark::before{content:"\00a0|\00a0"}
#header #revnumber{text-transform:capitalize}
#header #revnumber::after{content:"\00a0"}
#content>h1:first-child:not([class]){color:rgba(0,0,0,.85);border-bottom:1px solid #dddddf;padding-bottom:8px;margin-top:0;padding-top:1rem;margin-bottom:1.25rem}
#toc{border-bottom:1px solid #e7e7e9;padding-bottom:.5em}
#toc>ul{margin-left:.125em}
#toc ul.sectlevel0>li>a{font-style:italic}
#toc ul.sectlevel0 ul.sectlevel1{margin:.5em 0}
#toc ul{font-family:"Open Sans","DejaVu Sans",sans-serif;list-style-type:none}
#toc li{line-height:1.3334;margin-top:.3334em}
#toc a{text-decoration:none}
#toc a:active{text-decoration:underline}
#toctitle{color:#7a2518;font-size:1.2em}
@media screen and (min-width:768px){#toctitle{font-size:1.375em}
body.toc2{padding-left:15em;padding-right:0}
#toc.toc2{margin-top:0!important;background:#f8f8f7;position:fixed;width:15em;left:0;top:0;border-right:1px solid #e7e7e9;border-top-width:0!important;border-bottom-width:0!important;z-index:1000;padding:1.25em 1em;height:100%;overflow:auto}
#toc.toc2 #toctitle{margin-top:0;margin-bottom:.8rem;font-size:1.2em}
#toc.toc2>ul{font-size:.9em;margin-bottom:0}
#toc.toc2 ul ul{margin-left:0;padding-left:1em}
#toc.toc2 ul.sectlevel0 ul.sectlevel1{padding-left:0;margin-top:.5em;margin-bottom:.5em}
body.toc2.toc-right{padding-left:0;padding-right:15em}
body.toc2.toc-right #toc.toc2{border-right-width:0;border-left:1px solid #e7e7e9;left:auto;right:0}}
@media screen and (min-width:1280px){body.toc2{padding-left:20em;padding-right:0}
#toc.toc2{width:20em}
#toc.toc2 #toctitle{font-size:1.375em}
#toc.toc2>ul{font-size:.95em}
#toc.toc2 ul ul{padding-left:1.25em}
body.toc2.toc-right{padding-left:0;padding-right:20em}}
#content #toc{border:1px solid #e0e0dc;margin-bottom:1.25em;padding:1.25em;background:#f8f8f7;border-radius:4px}
#content #toc>:first-child{margin-top:0}
#content #toc>:last-child{margin-bottom:0}
#footer{max-width:none;background:rgba(0,0,0,.8);padding:1.25em}
#footer-text{color:hsla(0,0%,100%,.8);line-height:1.44}
#content{margin-bottom:.625em}
.sect1{padding-bottom:.625em}
@media screen and (min-width:768px){#content{margin-bottom:1.25em}
.sect1{padding-bottom:1.25em}}
.sect1:last-child{padding-bottom:0}
.sect1+.sect1{border-top:1px solid #e7e7e9}
#content h1>a.anchor,h2>a.anchor,h3>a.anchor,#toctitle>a.anchor,.sidebarblock>.content>.title>a.anchor,h4>a.anchor,h5>a.anchor,h6>a.anchor{position:absolute;z-index:1001;width:1.5ex;margin-left:-1.5ex;display:block;text-decoration:none!important;visibility:hidden;text-align:center;font-weight:400}
#content h1>a.anchor::before,h2>a.anchor::before,h3>a.anchor::before,#toctitle>a.anchor::before,.sidebarblock>.content>.title>a.anchor::before,h4>a.anchor::before,h5>a.anchor::before,h6>a.anchor::before{content:"\00A7";font-size:.85em;display:block;padding-top:.1em}
#content h1:hover>a.anchor,#content h1>a.anchor:hover,h2:hover>a.anchor,h2>a.anchor:hover,h3:hover>a.anchor,#toctitle:hover>a.anchor,.sidebarblock>.content>.title:hover>a.anchor,h3>a.anchor:hover,#toctitle>a.anchor:hover,.sidebarblock>.content>.title>a.anchor:hover,h4:hover>a.anchor,h4>a.anchor:hover,h5:hover>a.anchor,h5>a.anchor:hover,h6:hover>a.anchor,h6>a.anchor:hover{visibility:visible}
#content h1>a.link,h2>a.link,h3>a.link,#toctitle>a.link,.sidebarblock>.content>.title>a.link,h4>a.link,h5>a.link,h6>a.link{color:#ba3925;text-decoration:none}
#content h1>a.link:hover,h2>a.link:hover,h3>a.link:hover,#toctitle>a.link:hover,.sidebarblock>.content>.title>a.link:hover,h4>a.link:hover,h5>a.link:hover,h6>a.link:hover{color:#a53221}
details,.audioblock,.imageblock,.literalblock,.listingblock,.stemblock,.videoblock{margin-bottom:1.25em}
details{margin-left:1.25rem}
details>summary{cursor:pointer;display:block;position:relative;line-height:1.6;margin-bottom:.625rem;outline:none;-webkit-tap-highlight-color:transparent}
details>summary::-webkit-details-marker{display:none}
details>summary::before{content:"";border:solid transparent;border-left:solid;border-width:.3em 0 .3em .5em;position:absolute;top:.5em;left:-1.25rem;transform:translateX(15%)}
details[open]>summary::before{border:solid transparent;border-top:solid;border-width:.5em .3em 0;transform:translateY(15%)}
details>summary::after{content:"";width:1.25rem;height:1em;position:absolute;top:.3em;left:-1.25rem}
.admonitionblock td.content>.title,.audioblock>.title,.exampleblock>.title,.imageblock>.title,.listingblock>.title,.literalblock>.title,.stemblock>.title,.openblock>.title,.paragraph>.title,.quoteblock>.title,table.tableblock>.title,.verseblock>.title,.videoblock>.title,.dlist>.title,.olist>.title,.ulist>.title,.qlist>.title,.hdlist>.title{text-rendering:optimizeLegibility;text-align:left;font-family:"Noto Serif","DejaVu Serif",serif;font-size:1rem;font-style:italic}
table.tableblock.fit-content>caption.title{white-space:nowrap;width:0}
.paragraph.lead>p,#preamble>.sectionbody>[class=paragraph]:first-of-type p{font-size:1.21875em;line-height:1.6;color:rgba(0,0,0,.85)}
.admonitionblock>table{border-collapse:separate;border:0;background:none;width:100%}
.admonitionblock>table td.icon{text-align:center;width:80px}
.admonitionblock>table td.icon img{max-width:none}
.admonitionblock>table td.icon .title{font-weight:bold;font-family:"Open Sans","DejaVu Sans",sans-serif;text-transform:uppercase}
.admonitionblock>table td.content{padding-left:1.125em;padding-right:1.25em;border-left:1px solid #dddddf;color:rgba(0,0,0,.6);word-wrap:anywhere}
.admonitionblock>table td.content>:last-child>:last-child{margin-bottom:0}
.exampleblock>.content{border:1px solid #e6e6e6;margin-bottom:1.25em;padding:1.25em;background:#fff;border-radius:4px}
.exampleblock>.content>:first-child{margin-top:0}
.exampleblock>.content>:last-child{margin-bottom:0}
.sidebarblock{border:1px solid #dbdbd6;margin-bottom:1.25em;padding:1.25em;background:#f3f3f2;border-radius:4px}
.sidebarblock>:first-child{margin-top:0}
.sidebarblock>:last-child{margin-bottom:0}
.sidebarblock>.content>.title{color:#7a2518;margin-top:0;text-align:center}
.exampleblock>.content>:last-child>:last-child,.exampleblock>.content .olist>ol>li:last-child>:last-child,.exampleblock>.content .ulist>ul>li:last-child>:last-child,.exampleblock>.content .qlist>ol>li:last-child>:last-child,.sidebarblock>.content>:last-child>:last-child,.sidebarblock>.content .olist>ol>li:last-child>:last-child,.sidebarblock>.content .ulist>ul>li:last-child>:last-child,.sidebarblock>.content .qlist>ol>li:last-child>:last-child{margin-bottom:0}
.literalblock pre,.listingblock>.content>pre{border-radius:4px;overflow-x:auto;padding:1em;font-size:.8125em}
@media screen and (min-width:768px){.literalblock pre,.listingblock>.content>pre{font-size:.90625em}}
@media screen and (min-width:1280px){.literalblock pre,.listingblock>.content>pre{font-size:1em}}
.literalblock pre,.listingblock>.content>pre:not(.highlight),.listingblock>.content>pre[class=highlight],.listingblock>.content>pre[class^="highlight "]{background:#f7f7f8}
.literalblock.output pre{color:#f7f7f8;background:rgba(0,0,0,.9)}
.listingblock>.content{position:relative}
.listingblock code[data-lang]::before{display:none;content:attr(data-lang);position:absolute;font-size:.75em;top:.425rem;right:.5rem;line-height:1;text-transform:uppercase;color:inherit;opacity:.5}
.listingblock:hover code[data-lang]::before{display:block}
.listingblock.terminal pre .command::before{content:attr(data-prompt);padding-right:.5em;color:inherit;opacity:.5}
.listingblock.terminal pre .command:not([data-prompt])::before{content:"$"}
.listingblock pre.highlightjs{padding:0}
.listingblock pre.highlightjs>code{padding:1em;border-radius:4px}
.listingblock pre.prettyprint{border-width:0}
.prettyprint{background:#f7f7f8}
pre.prettyprint .linenums{line-height:1.45;margin-left:2em}
pre.prettyprint li{background:none;list-style-type:inherit;padding-left:0}
pre.prettyprint li code[data-lang]::before{opacity:1}
pre.prettyprint li:not(:first-child) code[data-lang]::before{display:none}
table.linenotable{border-collapse:separate;border:0;margin-bottom:0;background:none}
table.linenotable td[class]{color:inherit;vertical-align:top;padding:0;line-height:inherit;white-space:normal}
table.linenotable td.code{padding-left:.75em}
table.linenotable td.linenos,pre.pygments .linenos{border-right:1px solid;opacity:.35;padding-right:.5em;-webkit-user-select:none;-moz-user-select:none;-ms-user-select:none;user-select:none}
pre.pygments span.linenos{display:inline-block;margin-right:.75em}
.quoteblock{margin:0 1em 1.25em 1.5em;display:table}
.quoteblock:not(.excerpt)>.title{margin-left:-1.5em;margin-bottom:.75em}
.quoteblock blockquote,.quoteblock p{color:rgba(0,0,0,.85);font-size:1.15rem;line-height:1.75;word-spacing:.1em;letter-spacing:0;font-style:italic;text-align:justify}
.quoteblock blockquote{margin:0;padding:0;border:0}
.quoteblock blockquote::before{content:"\201c";float:left;font-size:2.75em;font-weight:bold;line-height:.6em;margin-left:-.6em;color:#7a2518;text-shadow:0 1px 2px rgba(0,0,0,.1)}
.quoteblock blockquote>.paragraph:last-child p{margin-bottom:0}
.quoteblock .attribution{margin-top:.75em;margin-right:.5ex;text-align:right}
.verseblock{margin:0 1em 1.25em}
.verseblock pre{font-family:"Open Sans","DejaVu Sans",sans-serif;font-size:1.15rem;color:rgba(0,0,0,.85);font-weight:300;text-rendering:optimizeLegibility}
.verseblock pre strong{font-weight:400}
.verseblock .attribution{margin-top:1.25rem;margin-left:.5ex}
.quoteblock .attribution,.verseblock .attribution{font-size:.9375em;line-height:1.45;font-style:italic}
.quoteblock .attribution br,.verseblock .attribution br{display:none}
.quoteblock .attribution cite,.verseblock .attribution cite{display:block;letter-spacing:-.025em;color:rgba(0,0,0,.6)}
.quoteblock.abstract blockquote::before,.quoteblock.excerpt blockquote::before,.quoteblock .quoteblock blockquote::before{display:none}
.quoteblock.abstract blockquote,.quoteblock.abstract p,.quoteblock.excerpt blockquote,.quoteblock.excerpt p,.quoteblock .quoteblock blockquote,.quoteblock .quoteblock p{line-height:1.6;word-spacing:0}
.quoteblock.abstract{margin:0 1em 1.25em;display:block}
.quoteblock.abstract>.title{margin:0 0 .375em;font-size:1.15em;text-align:center}
.quoteblock.excerpt>blockquote,.quoteblock .quoteblock{padding:0 0 .25em 1em;border-left:.25em solid #dddddf}
.quoteblock.excerpt,.quoteblock .quoteblock{margin-left:0}
.quoteblock.excerpt blockquote,.quoteblock.excerpt p,.quoteblock .quoteblock blockquote,.quoteblock .quoteblock p{color:inherit;font-size:1.0625rem}
.quoteblock.excerpt .attribution,.quoteblock .quoteblock .attribution{color:inherit;font-size:.85rem;text-align:left;margin-right:0}
p.tableblock:last-child{margin-bottom:0}
td.tableblock>.content{margin-bottom:1.25em;word-wrap:anywhere}
td.tableblock>.content>:last-child{margin-bottom:-1.25em}
table.tableblock,th.tableblock,td.tableblock{border:0 solid #dedede}
table.grid-all>*>tr>*{border-width:1px}
table.grid-cols>*>tr>*{border-width:0 1px}
table.grid-rows>*>tr>*{border-width:1px 0}
table.frame-all{border-width:1px}
table.frame-ends{border-width:1px 0}
table.frame-sides{border-width:0 1px}
table.frame-none>colgroup+*>:first-child>*,table.frame-sides>colgroup+*>:first-child>*{border-top-width:0}
table.frame-none>:last-child>:last-child>*,table.frame-sides>:last-child>:last-child>*{border-bottom-width:0}
table.frame-none>*>tr>:first-child,table.frame-ends>*>tr>:first-child{border-left-width:0}
table.frame-none>*>tr>:last-child,table.frame-ends>*>tr>:last-child{border-right-width:0}
table.stripes-all>*>tr,table.stripes-odd>*>tr:nth-of-type(odd),table.stripes-even>*>tr:nth-of-type(even),table.stripes-hover>*>tr:hover{background:#f8f8f7}
th.halign-left,td.halign-left{text-align:left}
th.halign-right,td.halign-right{text-align:right}
th.halign-center,td.halign-center{text-align:center}
th.valign-top,td.valign-top{vertical-align:top}
th.valign-bottom,td.valign-bottom{vertical-align:bottom}
th.valign-middle,td.valign-middle{vertical-align:middle}
table thead th,table tfoot th{font-weight:bold}
tbody tr th{background:#f7f8f7}
tbody tr th,tbody tr th p,tfoot tr th,tfoot tr th p{color:rgba(0,0,0,.8);font-weight:bold}
p.tableblock>code:only-child{background:none;padding:0}
p.tableblock{font-size:1em}
ol{margin-left:1.75em}
ul li ol{margin-left:1.5em}
dl dd{margin-left:1.125em}
dl dd:last-child,dl dd:last-child>:last-child{margin-bottom:0}
li p,ul dd,ol dd,.olist .olist,.ulist .ulist,.ulist .olist,.olist .ulist{margin-bottom:.625em}
ul.checklist,ul.none,ol.none,ul.no-bullet,ol.no-bullet,ol.unnumbered,ul.unstyled,ol.unstyled{list-style-type:none}
ul.no-bullet,ol.no-bullet,ol.unnumbered{margin-left:.625em}
ul.unstyled,ol.unstyled{margin-left:0}
li>p:empty:only-child::before{content:"";display:inline-block}
ul.checklist>li>p:first-child{margin-left:-1em}
ul.checklist>li>p:first-child>.fa-square-o:first-child,ul.checklist>li>p:first-child>.fa-check-square-o:first-child{width:1.25em;font-size:.8em;position:relative;bottom:.125em}
ul.checklist>li>p:first-child>input[type=checkbox]:first-child{margin-right:.25em}
ul.inline{display:flex;flex-flow:row wrap;list-style:none;margin:0 0 .625em -1.25em}
ul.inline>li{margin-left:1.25em}
.unstyled dl dt{font-weight:400;font-style:normal}
ol.arabic{list-style-type:decimal}
ol.decimal{list-style-type:decimal-leading-zero}
ol.loweralpha{list-style-type:lower-alpha}
ol.upperalpha{list-style-type:upper-alpha}
ol.lowerroman{list-style-type:lower-roman}
ol.upperroman{list-style-type:upper-roman}
ol.lowergreek{list-style-type:lower-greek}
.hdlist>table,.colist>table{border:0;background:none}
.hdlist>table>tbody>tr,.colist>table>tbody>tr{background:none}
td.hdlist1,td.hdlist2{vertical-align:top;padding:0 .625em}
td.hdlist1{font-weight:bold;padding-bottom:1.25em}
td.hdlist2{word-wrap:anywhere}
.literalblock+.colist,.listingblock+.colist{margin-top:-.5em}
.colist td:not([class]):first-child{padding:.4em .75em 0;line-height:1;vertical-align:top}
.colist td:not([class]):first-child img{max-width:none}
.colist td:not([class]):last-child{padding:.25em 0}
.thumb,.th{line-height:0;display:inline-block;border:4px solid #fff;box-shadow:0 0 0 1px #ddd}
.imageblock.left{margin:.25em .625em 1.25em 0}
.imageblock.right{margin:.25em 0 1.25em .625em}
.imageblock>.title{margin-bottom:0}
.imageblock.thumb,.imageblock.th{border-width:6px}
.imageblock.thumb>.title,.imageblock.th>.title{padding:0 .125em}
.image.left,.image.right{margin-top:.25em;margin-bottom:.25em;display:inline-block;line-height:0}
.image.left{margin-right:.625em}
.image.right{margin-left:.625em}
a.image{text-decoration:none;display:inline-block}
a.image object{pointer-events:none}
sup.footnote,sup.footnoteref{font-size:.875em;position:static;vertical-align:super}
sup.footnote a,sup.footnoteref a{text-decoration:none}
sup.footnote a:active,sup.footnoteref a:active{text-decoration:underline}
#footnotes{padding-top:.75em;padding-bottom:.75em;margin-bottom:.625em}
#footnotes hr{width:20%;min-width:6.25em;margin:-.25em 0 .75em;border-width:1px 0 0}
#footnotes .footnote{padding:0 .375em 0 .225em;line-height:1.3334;font-size:.875em;margin-left:1.2em;margin-bottom:.2em}
#footnotes .footnote a:first-of-type{font-weight:bold;text-decoration:none;margin-left:-1.05em}
#footnotes .footnote:last-of-type{margin-bottom:0}
#content #footnotes{margin-top:-.625em;margin-bottom:0;padding:.75em 0}
div.unbreakable{page-break-inside:avoid}
.big{font-size:larger}
.small{font-size:smaller}
.underline{text-decoration:underline}
.overline{text-decoration:overline}
.line-through{text-decoration:line-through}
.aqua{color:#00bfbf}
.aqua-background{background:#00fafa}
.black{color:#000}
.black-background{background:#000}
.blue{color:#0000bf}
.blue-background{background:#0000fa}
.fuchsia{color:#bf00bf}
.fuchsia-background{background:#fa00fa}
.gray{color:#606060}
.gray-background{background:#7d7d7d}
.green{color:#006000}
.green-background{background:#007d00}
.lime{color:#00bf00}
.lime-background{background:#00fa00}
.maroon{color:#600000}
.maroon-background{background:#7d0000}
.navy{color:#000060}
.navy-background{background:#00007d}
.olive{color:#606000}
.olive-background{background:#7d7d00}
.purple{color:#600060}
.purple-background{background:#7d007d}
.red{color:#bf0000}
.red-background{background:#fa0000}
.silver{color:#909090}
.silver-background{background:#bcbcbc}
.teal{color:#006060}
.teal-background{background:#007d7d}
.white{color:#bfbfbf}
.white-background{background:#fafafa}
.yellow{color:#bfbf00}
.yellow-background{background:#fafa00}
span.icon>.fa{cursor:default}
a span.icon>.fa{cursor:inherit}
.admonitionblock td.icon [class^="fa icon-"]{font-size:2.5em;text-shadow:1px 1px 2px rgba(0,0,0,.5);cursor:default}
.admonitionblock td.icon .icon-note::before{content:"\f05a";color:#19407c}
.admonitionblock td.icon .icon-tip::before{content:"\f0eb";text-shadow:1px 1px 2px rgba(155,155,0,.8);color:#111}
.admonitionblock td.icon .icon-warning::before{content:"\f071";color:#bf6900}
.admonitionblock td.icon .icon-caution::before{content:"\f06d";color:#bf3400}
.admonitionblock td.icon .icon-important::before{content:"\f06a";color:#bf0000}
.conum[data-value]{display:inline-block;color:#fff!important;background:rgba(0,0,0,.8);border-radius:50%;text-align:center;font-size:.75em;width:1.67em;height:1.67em;line-height:1.67em;font-family:"Open Sans","DejaVu Sans",sans-serif;font-style:normal;font-weight:bold}
.conum[data-value] *{color:#fff!important}
.conum[data-value]+b{display:none}
.conum[data-value]::after{content:attr(data-value)}
pre .conum[data-value]{position:relative;top:-.125em}
b.conum *{color:inherit!important}
.conum:not([data-value]):empty{display:none}
dt,th.tableblock,td.content,div.footnote{text-rendering:optimizeLegibility}
h1,h2,p,td.content,span.alt,summary{letter-spacing:-.01em}
p strong,td.content strong,div.footnote strong{letter-spacing:-.005em}
p,blockquote,dt,td.content,span.alt,summary{font-size:1.0625rem}
p{margin-bottom:1.25rem}
.sidebarblock p,.sidebarblock dt,.sidebarblock td.content,p.tableblock{font-size:1em}
.exampleblock>.content{background:#fffef7;border-color:#e0e0dc;box-shadow:0 1px 4px #e0e0dc}
.print-only{display:none!important}
@page{margin:1.25cm .75cm}
@media print{*{box-shadow:none!important;text-shadow:none!important}
html{font-size:80%}
a{color:inherit!important;text-decoration:underline!important}
a.bare,a[href^="#"],a[href^="mailto:"]{text-decoration:none!important}
a[href^="http:"]:not(.bare)::after,a[href^="https:"]:not(.bare)::after{content:"(" attr(href) ")";display:inline-block;font-size:.875em;padding-left:.25em}
abbr[title]{border-bottom:1px dotted}
abbr[title]::after{content:" (" attr(title) ")"}
pre,blockquote,tr,img,object,svg{page-break-inside:avoid}
thead{display:table-header-group}
svg{max-width:100%}
p,blockquote,dt,td.content{font-size:1em;orphans:3;widows:3}
h2,h3,#toctitle,.sidebarblock>.content>.title{page-break-after:avoid}
#header,#content,#footnotes,#footer{max-width:none}
#toc,.sidebarblock,.exampleblock>.content{background:none!important}
#toc{border-bottom:1px solid #dddddf!important;padding-bottom:0!important}
body.book #header{text-align:center}
body.book #header>h1:first-child{border:0!important;margin:2.5em 0 1em}
body.book #header .details{border:0!important;display:block;padding:0!important}
body.book #header .details span:first-child{margin-left:0!important}
body.book #header .details br{display:block}
body.book #header .details br+span::before{content:none!important}
body.book #toc{border:0!important;text-align:left!important;padding:0!important;margin:0!important}
body.book #toc,body.book #preamble,body.book h1.sect0,body.book .sect1>h2{page-break-before:always}
.listingblock code[data-lang]::before{display:block}
#footer{padding:0 .9375em}
.hide-on-print{display:none!important}
.print-only{display:block!important}
.hide-for-print{display:none!important}
.show-for-print{display:inherit!important}}
@media amzn-kf8,print{#header>h1:first-child{margin-top:1.25rem}
.sect1{padding:0!important}
.sect1+.sect1{border:0}
#footer{background:none}
#footer-text{color:rgba(0,0,0,.6);font-size:.9em}}
@media amzn-kf8{#header,#content,#footnotes,#footer{padding:0}}
</style>
<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/4.7.0/css/font-awesome.min.css">
<style>
/*! Stylesheet for CodeRay to loosely match GitHub themes | MIT License */
pre.CodeRay{background:#f7f7f8}
.CodeRay .line-numbers{border-right:1px solid;opacity:.35;padding:0 .5em 0 0;-webkit-user-select:none;-moz-user-select:none;-ms-user-select:none;user-select:none}
.CodeRay span.line-numbers{display:inline-block;margin-right:.75em}
.CodeRay .line-numbers strong{color:#000}
table.CodeRay{border-collapse:separate;border:0;margin-bottom:0;background:none}
table.CodeRay td{vertical-align:top;line-height:inherit}
table.CodeRay td.line-numbers{text-align:right}
table.CodeRay td.code{padding:0 0 0 .75em}
.CodeRay .debug{color:#fff!important;background:navy!important}
.CodeRay .annotation{color:#007}
.CodeRay .attribute-name{color:navy}
.CodeRay .attribute-value{color:#700}
.CodeRay .binary{color:#509}
.CodeRay .comment{color:#998;font-style:italic}
.CodeRay .char{color:#04d}
.CodeRay .char .content{color:#04d}
.CodeRay .char .delimiter{color:#039}
.CodeRay .class{color:#458;font-weight:bold}
.CodeRay .complex{color:#a08}
.CodeRay .constant,.CodeRay .predefined-constant{color:teal}
.CodeRay .color{color:#099}
.CodeRay .class-variable{color:#369}
.CodeRay .decorator{color:#b0b}
.CodeRay .definition{color:#099}
.CodeRay .delimiter{color:#000}
.CodeRay .doc{color:#970}
.CodeRay .doctype{color:#34b}
.CodeRay .doc-string{color:#d42}
.CodeRay .escape{color:#666}
.CodeRay .entity{color:#800}
.CodeRay .error{color:#808}
.CodeRay .exception{color:inherit}
.CodeRay .filename{color:#099}
.CodeRay .function{color:#900;font-weight:bold}
.CodeRay .global-variable{color:teal}
.CodeRay .hex{color:#058}
.CodeRay .integer,.CodeRay .float{color:#099}
.CodeRay .include{color:#555}
.CodeRay .inline{color:#000}
.CodeRay .inline .inline{background:#ccc}
.CodeRay .inline .inline .inline{background:#bbb}
.CodeRay .inline .inline-delimiter{color:#d14}
.CodeRay .inline-delimiter{color:#d14}
.CodeRay .important{color:#555;font-weight:bold}
.CodeRay .interpreted{color:#b2b}
.CodeRay .instance-variable{color:teal}
.CodeRay .label{color:#970}
.CodeRay .local-variable{color:#963}
.CodeRay .octal{color:#40e}
.CodeRay .predefined{color:#369}
.CodeRay .preprocessor{color:#579}
.CodeRay .pseudo-class{color:#555}
.CodeRay .directive{font-weight:bold}
.CodeRay .type{font-weight:bold}
.CodeRay .predefined-type{color:inherit}
.CodeRay .reserved,.CodeRay .keyword{color:#000;font-weight:bold}
.CodeRay .key{color:#808}
.CodeRay .key .delimiter{color:#606}
.CodeRay .key .char{color:#80f}
.CodeRay .value{color:#088}
.CodeRay .regexp .delimiter{color:#808}
.CodeRay .regexp .content{color:#808}
.CodeRay .regexp .modifier{color:#808}
.CodeRay .regexp .char{color:#d14}
.CodeRay .regexp .function{color:#404;font-weight:bold}
.CodeRay .string{color:#d20}
.CodeRay .string .string .string{background:#ffd0d0}
.CodeRay .string .content{color:#d14}
.CodeRay .string .char{color:#d14}
.CodeRay .string .delimiter{color:#d14}
.CodeRay .shell{color:#d14}
.CodeRay .shell .delimiter{color:#d14}
.CodeRay .symbol{color:#990073}
.CodeRay .symbol .content{color:#a60}
.CodeRay .symbol .delimiter{color:#630}
.CodeRay .tag{color:teal}
.CodeRay .tag-special{color:#d70}
.CodeRay .variable{color:#036}
.CodeRay .insert{background:#afa}
.CodeRay .delete{background:#faa}
.CodeRay .change{color:#aaf;background:#007}
.CodeRay .head{color:#f8f;background:#505}
.CodeRay .insert .insert{color:#080}
.CodeRay .delete .delete{color:#800}
.CodeRay .change .change{color:#66f}
.CodeRay .head .head{color:#f4f}
</style>
<style>
.hidden {
display: none;
}
.switch {
border-width: 1px 1px 0 1px;
border-style: solid;
border-color: #7a2518;
display: inline-block;
}
.switch--item {
padding: 10px;
background-color: #ffffff;
color: #7a2518;
display: inline-block;
cursor: pointer;
}
.switch--item.selected {
background-color: #7a2519;
color: #ffffff;
}
</style>
<script src="https://cdnjs.cloudflare.com/ajax/libs/zepto/1.2.0/zepto.min.js"></script>
<script type="text/javascript">
function addBlockSwitches() {
$('.primary').each(function() {
primary = $(this);
createSwitchItem(primary, createBlockSwitch(primary)).item.addClass("selected");
primary.children('.title').remove();
});
$('.secondary').each(function(idx, node) {
secondary = $(node);
primary = findPrimary(secondary);
switchItem = createSwitchItem(secondary, primary.children('.switch'));
switchItem.content.addClass('hidden');
findPrimary(secondary).append(switchItem.content);
secondary.remove();
});
}
function createBlockSwitch(primary) {
blockSwitch = $('<div class="switch"></div>');
primary.prepend(blockSwitch);
return blockSwitch;
}
function findPrimary(secondary) {
candidate = secondary.prev();
while (!candidate.is('.primary')) {
candidate = candidate.prev();
}
return candidate;
}
function createSwitchItem(block, blockSwitch) {
blockName = block.children('.title').text();
content = block.children('.content').first().append(block.next('.colist'));
item = $('<div class="switch--item">' + blockName + '</div>');
item.on('click', '', content, function(e) {
$(this).addClass('selected');
$(this).siblings().removeClass('selected');
e.data.siblings('.content').addClass('hidden');
e.data.removeClass('hidden');
});
blockSwitch.append(item);
return {'item': item, 'content': content};
}
$(addBlockSwitches);
</script>
</head>
<body class="article">
<div id="header">
<h1>Picocli 2.0: Groovy Scripts on Steroids</h1>
<div class="details">
<span id="revnumber">version 4.7.4</span>
</div>
</div>
<div id="content">
<div id="preamble">
<div class="sectionbody">
<div class="paragraph">
<p>Picocli 2.0 adds improved support for other JVM languages, especially Groovy.
Why use picocli when the Groovy language has built-in CLI support with the <a href="http://docs.groovy-lang.org/2.4.7/html/gapi/groovy/util/CliBuilder.html">CliBuilder</a> class?</p>
</div>
<div class="paragraph">
<p>You may like picocli’s usage help, which shows ANSI <a href="http://picocli.info/#_ansi_colors_and_styles">colors and styles</a>
by default. Another feature you may fancy is the command line
<a href="http://picocli.info/autocomplete.html">TAB autocompletion</a>. Finally, there is a slew of smaller features,
like the fact that your script needs zero lines of command line parsing code,
picocli’s <a href="http://picocli.info/#_subcommands">subcommand</a> support,
<a href="http://picocli.info/#_strongly_typed_everything">type conversion</a> for both options and positional parameters,
and <a href="http://picocli.info/#_tracing">parser tracing</a>, to name a few.</p>
</div>
<div class="paragraph text-center">
<p><span class="image"><img src="images/cli.jpg" alt="cli" width="20%"></span></p>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_example">Example</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Let’s take a look at an example. The <code>checksum.groovy</code> script below takes one or more file parameters,
and for each file prints out a checksum and the file name. The "checksum" algorithm is MD5 by default,
but users may specify a different MessageDigest algorithm. Users can request usage help with the
<code>-h</code> or <code>--help</code> option.</p>
</div>
<div class="listingblock">
<div class="content">
<pre class="CodeRay highlight nowrap"><code data-lang="groovy"><span class="annotation">@Grab</span>(<span class="string"><span class="delimiter">'</span><span class="content">info.picocli:picocli:2.0.3</span><span class="delimiter">'</span></span>)
<span class="annotation">@picocli</span>.groovy.PicocliScript
<span class="keyword">import</span> <span class="include">groovy.transform.Field</span>
<span class="keyword">import</span> <span class="include">java.security.MessageDigest</span>
<span class="keyword">import</span> <span class="include">static</span> <span class="include">picocli.CommandLine.*</span>
<span class="annotation">@Parameters</span>(arity=<span class="string"><span class="delimiter">"</span><span class="content">1</span><span class="delimiter">"</span></span>, paramLabel=<span class="string"><span class="delimiter">"</span><span class="content">FILE</span><span class="delimiter">"</span></span>, description=<span class="string"><span class="delimiter">"</span><span class="content">The file(s) whose checksum to calculate.</span><span class="delimiter">"</span></span>)
<span class="annotation">@Field</span> <span class="predefined-type">File</span><span class="type">[]</span> files
<span class="annotation">@Option</span>(names = [<span class="string"><span class="delimiter">"</span><span class="content">-a</span><span class="delimiter">"</span></span>, <span class="string"><span class="delimiter">"</span><span class="content">--algorithm</span><span class="delimiter">"</span></span>], description = [
<span class="string"><span class="delimiter">"</span><span class="content">MD2, MD5, SHA-1, SHA-256, SHA-384, SHA-512,</span><span class="delimiter">"</span></span>,
<span class="string"><span class="delimiter">"</span><span class="content"> or any other MessageDigest algorithm.</span><span class="delimiter">"</span></span>])
<span class="annotation">@Field</span> <span class="predefined-type">String</span> algorithm = <span class="string"><span class="delimiter">"</span><span class="content">MD5</span><span class="delimiter">"</span></span>
<span class="annotation">@Option</span>(names= [<span class="string"><span class="delimiter">"</span><span class="content">-h</span><span class="delimiter">"</span></span>, <span class="string"><span class="delimiter">"</span><span class="content">--help</span><span class="delimiter">"</span></span>], usageHelp= <span class="predefined-constant">true</span>, description= <span class="string"><span class="delimiter">"</span><span class="content">Show this help message and exit.</span><span class="delimiter">"</span></span>)
<span class="annotation">@Field</span> <span class="type">boolean</span> helpRequested
files.each {
println <span class="predefined-type">MessageDigest</span>.getInstance(algorithm).digest(<span class="local-variable">it</span>.bytes).encodeHex().toString() + <span class="string"><span class="delimiter">"</span><span class="char">\t</span><span class="delimiter">"</span></span> + <span class="local-variable">it</span>
}</code></pre>
</div>
</div>
<div class="paragraph">
<p>When run in the <code>$picocli-home/examples/src/main/groovy/picocli/examples</code> directory,
this example script gives the following results:</p>
</div>
<div class="listingblock">
<div class="content">
<pre class="CodeRay highlight nowrap"><code data-lang="bash">$ groovy checksum.groovy *.*
4995d24bbb3adf67e2120c36dd3027b7 checksum.groovy
a03c852de017f9303fcc373c7adafac6 checksum-with-banner.groovy
1ee567193bf41cc835ce76b6ca29ed30 checksum-without-base.groovy</code></pre>
</div>
</div>
<div class="paragraph">
<p>Invoking the script with the <code>-h</code> or <code>--help</code> option shows the usage help message
with ANSI colors and styles below:</p>
</div>
<div class="paragraph">
<p><span class="image"><img src="images/GroovyChecksum.png" alt="Usage help with ANSI colors and styles"></span></p>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_wheres_the_code">Where’s the Code?</h2>
<div class="sectionbody">
<div class="paragraph">
<p>You may have noticed that the above script does not contain any logic for parsing the command
line arguments or for handling requests for usage help.</p>
</div>
<div class="paragraph text-center">
<p><span class="image"><img src="images/WhereIsMyCode.png" alt="Dude" width="35%"></span></p>
</div>
<div class="paragraph">
<p>Without the <code>@picocli.groovy.PicocliScript</code> annotation, the script code would look something like this:</p>
</div>
<div class="listingblock">
<div class="content">
<pre class="CodeRay highlight nowrap"><code data-lang="groovy"><span class="type">class</span> <span class="class">Checksum</span> {
<span class="annotation">@Parameters</span>(arity = <span class="string"><span class="delimiter">"</span><span class="content">1</span><span class="delimiter">"</span></span>, paramLabel = <span class="string"><span class="delimiter">"</span><span class="content">FILE</span><span class="delimiter">"</span></span>, description = <span class="string"><span class="delimiter">"</span><span class="content">...</span><span class="delimiter">"</span></span>)
<span class="predefined-type">File</span><span class="type">[]</span> files
<span class="annotation">@Option</span>(names = [<span class="string"><span class="delimiter">"</span><span class="content">-a</span><span class="delimiter">"</span></span>, <span class="string"><span class="delimiter">"</span><span class="content">--algorithm</span><span class="delimiter">"</span></span>], description = [<span class="string"><span class="delimiter">"</span><span class="content">...</span><span class="delimiter">"</span></span>])
<span class="predefined-type">String</span> algorithm = <span class="string"><span class="delimiter">"</span><span class="content">MD5</span><span class="delimiter">"</span></span>
<span class="annotation">@Option</span>(names = [<span class="string"><span class="delimiter">"</span><span class="content">-h</span><span class="delimiter">"</span></span>, <span class="string"><span class="delimiter">"</span><span class="content">--help</span><span class="delimiter">"</span></span>], usageHelp = <span class="predefined-constant">true</span>, description = <span class="string"><span class="delimiter">"</span><span class="content">...</span><span class="delimiter">"</span></span>)
<span class="type">boolean</span> helpRequested
}
<span class="predefined-type">Checksum</span> checksum = <span class="keyword">new</span> <span class="predefined-type">Checksum</span>()
CommandLine commandLine = <span class="keyword">new</span> CommandLine(checksum)
<span class="keyword">try</span> {
commandLine.parse(args)
<span class="keyword">if</span> (commandLine.usageHelpRequested) {
commandLine.usage(<span class="predefined-type">System</span>.out)
} <span class="keyword">else</span> {
checksum.files.each {
<span class="type">byte</span><span class="type">[]</span> digest = <span class="predefined-type">MessageDigest</span>.getInstance(checksum.algorithm).digest(<span class="local-variable">it</span>.bytes)
println digest.encodeHex().toString() + <span class="string"><span class="delimiter">"</span><span class="char">\t</span><span class="delimiter">"</span></span> + <span class="local-variable">it</span>
}
}
} <span class="keyword">catch</span> (ParameterException ex) {
println ex.message
commandLine.usage(<span class="predefined-type">System</span>.out)
}</code></pre>
</div>
</div>
<div class="paragraph">
<p>The above example has explicit code to parse the command line, deal with invalid user input,
and check for usage help requests.
The first version of the script did not have any of this boilerplate code.</p>
</div>
<div class="paragraph">
<p>Let’s take a look at how this works.</p>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_basescript">Basescript</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Scripts annotated with <code>@picocli.groovy.PicocliScript</code> are automatically transformed to use
<code>picocli.groovy.PicocliBaseScript</code> as their base class.
This turns a Groovy script into a picocli-based command line application.</p>
</div>
<div class="paragraph text-center">
<p><span class="image"><img src="images/AllYourBase.png" alt="AllYourBase" width="35%"></span></p>
</div>
<div class="paragraph">
<p>When the script is run, Groovy calls the script’s <code>run</code> method.
The <code>PicocliBaseScript::run</code> method takes care of parsing the command line and populating the script
fields with the results. The run method does the following:</p>
</div>
<div class="ulist">
<ul>
<li>
<p>First, <code>@Field</code> variables annotated with <code>@Option</code> or <code>@Parameters</code> are initialized from the command line arguments.</p>
</li>
<li>
<p>If the user input was invalid, an error message is printed followed by the usage help message.</p>
</li>
<li>
<p>If the user requested usage help or version information, this is printed to the console and the script exits.</p>
</li>
<li>
<p>Otherwise, the script body is executed.</p>
</li>
</ul>
</div>
<div class="paragraph">
<p>This behavior can be customized, see the <a href="http://picocli.info/apidocs-all/info.picocli.groovy/picocli/groovy/PicocliBaseScript.html#run--">PicocliBaseScript javadoc</a> for more details.</p>
</div>
<div class="paragraph">
<p>In addition to changing the script base class, the <code>@PicocliScript</code> annotation also allows Groovy
scripts to use the <code>@Command</code> annotation directly, without introducing a helper class.
The picocli parser will look for this annotation on the
class containing the <code>@Option</code> and <code>@Parameters</code>-annotated fields. The same custom
<a href="http://picocli.info/apidocs-all/info.picocli.groovy/picocli/groovy/PicocliScriptASTTransformation.html">AST transformation</a>
that changes the script’s base class also moves any <code>@Command</code> annotation in the script to this
transformed class so the picocli parser can pick it up.</p>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_usage_help_with_colors">Usage Help With Colors</h2>
<div class="sectionbody">
<div class="paragraph">
<p>The <code>@Command</code> annotation lets you customize parts of the <a href="http://picocli.info/#_usage_help">usage help</a> message like command name, description, headers, footers etc.</p>
</div>
<div class="paragraph">
<p>Let’s add some bells and whistles to the example script.
(Credit to <a href="http://patorjk.com/software/taag/" class="bare">http://patorjk.com/software/taag/</a> for the ASCII Art Generator.)</p>
</div>
<div class="listingblock">
<div class="content">
<pre class="CodeRay highlight nowrap"><code data-lang="groovy"><span class="annotation">@Grab</span>(<span class="string"><span class="delimiter">'</span><span class="content">info.picocli:picocli:2.0.3</span><span class="delimiter">'</span></span>)
<span class="annotation">@Command</span>(header = [
<span class="error">$</span><span class="regexp"><span class="delimiter">/</span><span class="content">@|bold,green ___ ___ _ _ |@</span><span class="delimiter">/</span></span><span class="error">$</span>,
<span class="error">$</span><span class="regexp"><span class="delimiter">/</span><span class="content">@|bold,green </span><span class="delimiter">/</span></span> __|_ _ ___ _____ ___ _ / __| |_ ___ __| |__ ____ _ _ __ |<span class="error">@</span><span class="regexp"><span class="delimiter">/</span><span class="content">$</span><span class="content">,</span></span><span class="error">
</span> <span class="error">$</span>/<span class="error">@</span>|bold,green | (_ | <span class="string"><span class="delimiter">'</span><span class="content">_/ _ \/ _ \ V / || | | (__| </span><span class="delimiter">'</span></span> <span class="error">\</span>/ -_) _| <span class="regexp"><span class="delimiter">/</span><span class="content"> </span><span class="delimiter">/</span></span>(_-< || | <span class="string"><span class="delimiter">'</span><span class="content"> \ |@/$,</span></span><span class="error">
</span> <span class="error">$</span>/<span class="error">@</span>|bold,green <span class="error">\</span>___|_| <span class="error">\</span>___/<span class="error">\</span>___/<span class="error">\</span>_/ <span class="error">\</span>_, | <span class="error">\</span>___|_||_<span class="error">\</span>___<span class="error">\</span>__|_<span class="error">\</span>_<span class="error">\</span>/__/<span class="error">\</span>_,_|_|_|_||<span class="error">@</span><span class="regexp"><span class="delimiter">/</span><span class="content">$</span><span class="content">,</span></span><span class="error">
</span> <span class="error">$</span>/<span class="error">@</span>|bold,green |__/ |<span class="error">@</span><span class="regexp"><span class="delimiter">/</span><span class="content">$</span></span><span class="error">
</span> ],
description = <span class="string"><span class="delimiter">"</span><span class="content">Print a checksum of each specified FILE.</span><span class="delimiter">"</span></span>,
version = <span class="string"><span class="delimiter">'</span><span class="content">checksum v1.2.3</span><span class="delimiter">'</span></span>, showDefaultValues = <span class="predefined-constant">true</span>,
footerHeading = <span class="string"><span class="delimiter">"</span><span class="content">%nFor more details, see:%n</span><span class="delimiter">"</span></span>,
footer = [<span class="string"><span class="delimiter">"</span><span class="content">[1] https://docs.oracle.com/javase/9/docs/specs/security/standard-names.html</span><span class="delimiter">"</span></span>,
<span class="string"><span class="delimiter">"</span><span class="content">ASCII Art thanks to http://patorjk.com/software/taag/</span><span class="delimiter">"</span></span>]
)
<span class="annotation">@picocli</span>.groovy.PicocliScript
<span class="keyword">import</span> <span class="include">groovy.transform.Field</span>
<span class="keyword">import</span> <span class="include">java.security.MessageDigest</span>
<span class="keyword">import</span> <span class="include">static</span> <span class="include">picocli.CommandLine.*</span>
<span class="annotation">@Parameters</span>(arity=<span class="string"><span class="delimiter">"</span><span class="content">1</span><span class="delimiter">"</span></span>, paramLabel=<span class="string"><span class="delimiter">"</span><span class="content">FILE</span><span class="delimiter">"</span></span>, description=<span class="string"><span class="delimiter">"</span><span class="content">The file(s) whose checksum to calculate.</span><span class="delimiter">"</span></span>)
<span class="annotation">@Field</span> <span class="directive">private</span> <span class="predefined-type">File</span><span class="type">[]</span> files
<span class="annotation">@Option</span>(names = [<span class="string"><span class="delimiter">"</span><span class="content">-a</span><span class="delimiter">"</span></span>, <span class="string"><span class="delimiter">"</span><span class="content">--algorithm</span><span class="delimiter">"</span></span>], description = [
<span class="string"><span class="delimiter">"</span><span class="content">MD2, MD5, SHA-1, SHA-256, SHA-384, SHA-512, or</span><span class="delimiter">"</span></span>,
<span class="string"><span class="delimiter">"</span><span class="content"> any other MessageDigest algorithm. See [1] for more details.</span><span class="delimiter">"</span></span>])
<span class="annotation">@Field</span> <span class="directive">private</span> <span class="predefined-type">String</span> algorithm = <span class="string"><span class="delimiter">"</span><span class="content">MD5</span><span class="delimiter">"</span></span>
<span class="annotation">@Option</span>(names= [<span class="string"><span class="delimiter">"</span><span class="content">-h</span><span class="delimiter">"</span></span>, <span class="string"><span class="delimiter">"</span><span class="content">--help</span><span class="delimiter">"</span></span>], usageHelp=<span class="predefined-constant">true</span>, description=<span class="string"><span class="delimiter">"</span><span class="content">Show this help message and exit.</span><span class="delimiter">"</span></span>)
<span class="annotation">@Field</span> <span class="directive">private</span> <span class="type">boolean</span> helpRequested
<span class="annotation">@Option</span>(names= [<span class="string"><span class="delimiter">"</span><span class="content">-V</span><span class="delimiter">"</span></span>, <span class="string"><span class="delimiter">"</span><span class="content">--version</span><span class="delimiter">"</span></span>], versionHelp=<span class="predefined-constant">true</span>, description=<span class="string"><span class="delimiter">"</span><span class="content">Show version info and exit.</span><span class="delimiter">"</span></span>)
<span class="annotation">@Field</span> <span class="directive">private</span> <span class="type">boolean</span> versionInfoRequested
files.each {
println <span class="predefined-type">MessageDigest</span>.getInstance(algorithm).digest(<span class="local-variable">it</span>.bytes).encodeHex().toString() + <span class="string"><span class="delimiter">"</span><span class="char">\t</span><span class="delimiter">"</span></span> + <span class="local-variable">it</span>
}</code></pre>
</div>
</div>
<div class="paragraph">
<p>The new version of the script adds a header and footer, and the ability to print version information.
All text displayed in the usage help message and version information may contain format specifiers
like the <code>%n</code> line separator.</p>
</div>
<div class="paragraph">
<p>The usage help message can also display ANSI colors and styles.
Picocli supports a simple markup syntax where <code>@|</code> starts an ANSI styled section and <code>|@</code> ends it.
Immediately following the <code>@|</code> is a comma-separated list of colors and styles,
like <code>@|STYLE1[,STYLE2]…​ text|@</code>.
See the picocli <a href="http://picocli.info/#_usage_help_with_styles_and_colors">user manual</a> for details on what colors and styles are available.</p>
</div>
<div class="paragraph">
<p>The usage help message for the new script looks like this:</p>
</div>
<div class="paragraph">
<p><span class="image"><img src="images/GroovyChecksumWithBanner.png" alt="Customized header and footer with styles and colors"></span></p>
</div>
<div class="paragraph">
<p>The <code>@Command</code> annotation also has a <code>version = "checksum v1.2.3"</code> attribute.
This version string is printed when the user specifies <code>--version</code> on the command line because
we declared an <code>@Option</code> with that name with attribute <code>versionHelp = true</code>.</p>
</div>
<div class="listingblock">
<div class="content">
<pre class="CodeRay highlight nowrap"><code data-lang="bash">$ groovy checksum-with-banner.groovy --version
checksum v1.2.3</code></pre>
</div>
</div>
<div class="paragraph">
<p>For more details, see the <a href="http://picocli.info/#_version_help">Version Help</a> section of the user manual.</p>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_conclusion">Conclusion</h2>
<div class="sectionbody">
<div class="paragraph">
<p>The <code>@PicocliScript</code> annotation allows Groovy scripts to omit boilerplate code and while adding powerful common command line application functionality.
In the final version of our example script, most of the code is actually description text for the usage help message.</p>
</div>
<div class="paragraph">
<p>There is a lot more to picocli, give it a try!</p>
</div>
<div class="paragraph">
<p>Please star the <a href="https://github.com/remkop/picocli">project on GitHub</a> if you like it and tell your friends!</p>
</div>
</div>
</div>
</div>
<div id="footer">
<div id="footer-text">
Version 4.7.4<br>
Last updated 2023-03-12 17:36:44 +0900
</div>
</div>
</body>
</html>