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1 package gnu.text;
2 import java.text.FieldPosition  ;
3
4 public class RomanIntegerFormat extends java.text.NumberFormat
5 {
6 private static RomanIntegerFormat newRoman;
7 private static RomanIntegerFormat oldRoman;
8
9 public boolean oldStyle;
10
11 public RomanIntegerFormat(boolean oldStyle)
12 {
13 this.oldStyle = oldStyle;
14 }
15
16 public RomanIntegerFormat()
17 {
18 }
19
20 public static RomanIntegerFormat getInstance (boolean oldStyle)
21 {
22 if (oldStyle)
23 {
24 if (oldRoman == null)
25 oldRoman = new RomanIntegerFormat(true);
26 return oldRoman;
27 }
28 else
29 {
30 if (newRoman == null)
31 newRoman = new RomanIntegerFormat(false);
32 return newRoman;
33 }
34 }
35
36 static final String codes = "IVXLCDM";
37
38 public static String format(int num, boolean oldStyle)
39 {
40 if (num <= 0 || num >= 4999)
41 return Integer.toString(num);
42 StringBuffer sbuf = new StringBuffer (20);
43 int power = 3;
44 int unit = 1000;
45 for ( ; power >= 0; unit = unit / 10, power--)
46 {
47 int digit = num / unit;
48 num -= digit * unit;
49 if (digit == 0)
50 continue;
51 if (! oldStyle && (digit == 4 || digit == 9))
52 {
53 sbuf.append(codes.charAt(2 * power));
54 sbuf.append(codes.charAt(2 * power + (digit + 1) / 5));
55 continue;
56 }
57 int rest = digit;
58 if (rest >= 5)
59 {
60 sbuf.append(codes.charAt(2 * power + 1));
61 rest -= 5;
62 }
63 while (--rest >= 0)
64 {
65 sbuf.append(codes.charAt(2 * power));
66 }
67 }
68 return sbuf.toString();
69 }
70
71 public static String format(int num)
72 {
73 return format(num, false);
74 }
75
76 public StringBuffer format(long num, StringBuffer sbuf, FieldPosition fpos)
77 {
78 String str;
79 if (num > 0 && num < (oldStyle ? 4999 : 3999))
80 str = format((int) num, oldStyle);
81 else
82 str = Long.toString(num);
83 if (fpos != null)
84 {
85 long tval = 1;
87 int len = str.length();
88 for (int i = len; --i > 0; )
89 tval = 10 * tval + 9;
90 StringBuffer tbuf = new StringBuffer (len);
92 new java.text.DecimalFormat ("0").format(tval, tbuf, fpos);
93 }
94 sbuf.append(str);
95 return sbuf;
96 }
97
98 public StringBuffer format(double num, StringBuffer sbuf, FieldPosition fpos)
99 {
100 long inum = (long) num;
101 if ((double) inum == num)
102 return format(inum, sbuf, fpos);
103 sbuf.append(Double.toString(num));
104 return sbuf;
105 }
106
107 public java.lang.Number parse(String text, java.text.ParsePosition status)
108 {
109 throw new Error ("RomanIntegerFormat.parseObject - not implemented");
110 }
111 }
112 |
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