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1
6
7 package cpmake;
8
9 import java.util.*;
10
11
12 class Printf
13 {
14 private static String  s_knownFlags = "dfxXs";
16 public static void main(String [] commandline)
17 {
18 Object [] args = new Object [1];
19
20 args[0] = new Double (1234.1234);
21 System.out.println(Printf.print("double = %2.2f", args));
22 }
23
24 public static String print(String pattern, Object [] args)
25 {
26 StringBuffer result = new StringBuffer ();
27 String [] parts = split(pattern);
28 int paramCount = 0;
29
30 for (int I = 0; I < parts.length; I++)
31 {
32 if (parts[I].startsWith("%"))
33 {
34 result.append(processArg(parts[I], args[paramCount]));
35 paramCount++;
36 }
37 else
38 result.append(parts[I]);
39 }
40
41 return (result.toString());
42 }
43
44 private static String processArg(String tag, Object arg)
46 {
47 char[] ctag = tag.toCharArray();
48 String ret = null;
49
50 switch (ctag[ctag.length-1])
51 {
52 case 'd':
53 case 'f':
54 case 'l':
55 ret = arg.toString();
56 if (ctag.length > 2)
57 ret = formatNumber(ret, new String (ctag, 1, ctag.length-2));
58 break;
59 case 'x':
60 ret = Long.toHexString(((Number )arg).longValue()).toLowerCase();
61 if (ctag.length > 2)
62 ret = formatNumber(ret, new String (ctag, 1, ctag.length-2));
63 break;
64 case 'X':
65 ret = Long.toHexString(((Number )arg).longValue()).toUpperCase();
66 if (ctag.length > 2)
67 ret = formatNumber(ret, new String (ctag, 1, ctag.length-2));
68 break;
69 case 's':
70 ret = arg.toString();
71 break;
72 default:
73 ret = arg.toString();
74 }
75
76 return (ret);
77 }
78
79 private static String formatNumber(String number, String format)
81 {
82 boolean leftJustify = false;
83 boolean zeroPad = false;
84 int startPos = 0;
85 int width = 0;
86 int numberWidth = 0;
87 int precision = 0;
88 boolean setPrecision = false;
89 int precisionIndex = 0;
90
91
92 if (format.startsWith("-"))
93 {
94 leftJustify = true;
95 startPos = 1;
96 }
97 else if (format.startsWith("0"))
98 {
99 zeroPad = true;
100 startPos = 1;
101 }
102
103 if ((precisionIndex = format.indexOf('.')) != -1)
104 {
105 setPrecision = true;
106 precision = Integer.parseInt(format.substring(precisionIndex+1, format.length()));
107 }
108 else
109 precisionIndex = format.length();
110
111 if (precisionIndex != startPos)
112 width = Integer.parseInt(format.substring(startPos, precisionIndex));
113
114 if (setPrecision)
115 {
116 int pind;
117
118 if ((pind = number.indexOf('.')) != -1)
119 {
120 number = String.valueOf(round(Double.parseDouble(number), precision));
121 pind = number.indexOf('.');
122 }
123 else
124 pind = number.length();
125
126 char[] newnum;
127 if ((pind + precision + 1) > number.length())
128 newnum = new char[pind + precision + 1];
129 else
130 newnum = new char[number.length()];
131 Arrays.fill(newnum, '0');
132 newnum[pind] = '.';
133 number = new String (copyArray(newnum, number.toCharArray()));
134 }
135
136 if (number.length() < width)
137 {
138 char[] newnum = new char[width];
139
140 if (zeroPad)
141 Arrays.fill(newnum, '0');
142 else
143 Arrays.fill(newnum, ' ');
144
145 if (leftJustify)
146 number = new String (copyArray(newnum, number.toCharArray()));
147 else
148 number = new String (copyArray(newnum, number.toCharArray(), width - number.length()));
149 }
150
151 return (number);
152 }
153
154 private static char[] copyArray(char[] dest, char[] src)
156 {
157 return (copyArray(dest, src, 0));
158 }
159
160 private static char[] copyArray(char[] dest, char[] src, int startOffset)
162 {
163 if (dest.length < src.length)
164 {
165 System.out.println("Source size = " + src.length);
166 System.out.println("Dest size = " + dest.length);
167 System.exit(1);
168 }
169
170 for (int I = 0; I < src.length; I++)
171 dest[I+startOffset] = src[I];
172
173 return (dest);
174 }
175
176 private static double round(double num, int precision)
178 {
179 long round;
180
181 round = Math.round(num * Math.pow(10, precision));
182 return (round / Math.pow(10, precision));
183 }
184
185 private static String [] split(String pattern)
187 {
188 char[] pat = pattern.toCharArray();
189 Vector ret = new Vector();
190 int lastIndex = 0;
191
192 for (int I = 0; I < (pat.length-1); I++)
194 {
195 if (pat[I] == '%')
196 {
197 if (pat[I+1] != '%')
198 {
199 ret.add(new String (pat, lastIndex, (I - lastIndex)));
200 lastIndex = I;
201 for (int J = I; J < pat.length; J++)
202 {
203 if (s_knownFlags.indexOf(pat[J]) != -1)
204 {
205 ret.add(new String (pat, lastIndex, (J - lastIndex)+1));
206 lastIndex = J+1;
207 I = J;
208 break;
209 }
210 }
211 }
212 else
213 {
214 I++;
215 ret.add(new String (pat, lastIndex, (I - lastIndex)));
216 lastIndex = I+1;
217 }
218 }
219 }
220
221 if (lastIndex < pat.length)
222 ret.add(new String (pat, lastIndex, (pat.length - lastIndex)));
223
224 return ((String [])ret.toArray(new String [1]));
225 }
226
227 }
228
229 |
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