[ GroovyGN ] Padding Strings

Source From Here
Preface
Groovy extends the String class with a couple of padding methods. These methods allows us to define a fixed width a String value must occupy. If the Stringitself is less than the fixed width then the space is padded with spaces or any other character or String we define. We can pad to the left or the right of the Stringor both left and right and put the String in the center.

Sample Code
These methods are especially useful when we create Groovy scripts that run on the console and we want to format some output.

view plaincopy to clipboardprint?

1. assert '   Groovy   ' == 'Groovy'.center(12)  
2. assert 'Groovy      ' == "Groovy".padRight(12)  
3. assert '      Groovy' == /Groovy/.padLeft(12)  
4.   
5. assert '---Groovy---' == "Groovy".center(12, '-')  
6. assert 'Groovy * * *' == "Groovy".padRight(12, ' *')  
7. assert 'Groovy Groovy Groovy' == 'Groovy'.padLeft(20, 'Groovy ')  
8.   
9. def createOutput = {  
10.     def table = [  
11.         // Page,    Response time, Size  
12.         ['page1.html',        200, 1201],  
13.         ['page2.html',         42, 8853],  
14.         ['page3.html',         98, 3432],  
15.         ['page4.html',        432, 9081]  
16.     ]  
17.   
18.     def total = { data, index ->  
19.         data.inject(0) { result, row -> result += row[index] }  
20.     }  
21.     def totalTime = total.curry(table, 1)  
22.     def totalSize = total.curry(table, 2)  
23.   
24.     def out = new StringBuffer()  
25.     out << ' Summary '.center(15, "*") << '\n\n'  
26.     out << 'Total pages:'.padRight(25)  
27.     out << table.size().toString().padLeft(6) << '\n'  
28.     out << 'Total response time (ms):'.padRight(25)  
29.     out << totalTime().toString().padLeft(6) << '\n'  
30.     out << 'Total size (KB):'.padRight(25)  
31.     out << totalSize().toString().padLeft(6) << '\n\n'  
32.   
33.     out << ' Details '.center(15, "*") << '\n\n'  
34.     table.each {  
35.         out << it[0].padRight(14)  
36.         out << it[1].toString().padLeft(5)  
37.         out << it[2].toString().padLeft(8)  
38.         out << '\n'  
39.     }  
40.     out.toString()  
41. }  
42.   
43. assert '''\  
44. *** Summary ***  
45.   
46. Total pages:                  4  
47. Total response time (ms):   772  
48. Total size (KB):          22567  
49.            
50. *** Details ***  
51.   
52. page1.html      200    1201  
53. page2.html       42    8853  
54. page3.html       98    3432  
55. page4.html      432    9081  
56. ''' == createOutput()