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1 package com.thaiopensource.util;
2
3 import java.net.URL  ;
4 import java.net.MalformedURLException ;
5 import java.io.UnsupportedEncodingException ;
6
7 public class Uri {
8 private static String utf8 = "UTF-8";
9
10 public static boolean isValid(String s) {
11 return isValidPercent(s) && isValidFragment(s) && isValidScheme(s);
12 }
13
14 private static final String HEX_DIGITS = "0123456789abcdef";
15
16 public static String escapeDisallowedChars(String s) {
17 StringBuffer buf = null;
18 int len = s.length();
19 int done = 0;
20 for (;;) {
21 int i = done;
22 for (;;) {
23 if (i == len) {
24 if (done == 0)
25 return s;
26 break;
27 }
28 if (isExcluded(s.charAt(i)))
29 break;
30 i++;
31 }
32 if (buf == null)
33 buf = new StringBuffer ();
34 if (i > done) {
35 buf.append(s.substring(done, i));
36 done = i;
37 }
38 if (i == len)
39 break;
40 for (i++; i < len && isExcluded(s.charAt(i)); i++)
41 ;
42 String tem = s.substring(done, i);
43 byte[] bytes;
44 try {
45 bytes = tem.getBytes(utf8);
46 }
47 catch (UnsupportedEncodingException e) {
48 utf8 = "UTF8";
49 try {
50 bytes = tem.getBytes(utf8);
51 }
52 catch (UnsupportedEncodingException e2) {
53 return s;
55 }
56 }
57 for (int j = 0; j < bytes.length; j++) {
58 buf.append('%');
59 buf.append(HEX_DIGITS.charAt((bytes[j] & 0xFF) >> 4));
60 buf.append(HEX_DIGITS.charAt(bytes[j] & 0xF));
61 }
62 done = i;
63 }
64 return buf.toString();
65 }
66
67 private static final String excluded = "<>\"{}|\\^`";
68
69 private static boolean isExcluded(char c) {
70 return c <= 0x20 || c >= 0x7F || excluded.indexOf(c) >= 0;
71 }
72
73 private static boolean isAlpha(char c) {
74 return ('a' <= c && c <= 'z') || ('A' <= c && c <= 'Z');
75 }
76
77 private static boolean isHexDigit(char c) {
78 return ('a' <= c && c <= 'f') || ('A' <= c && c <= 'F') || isDigit(c);
79 }
80
81 private static boolean isDigit(char c) {
82 return '0' <= c && c <= '9';
83 }
84
85 private static boolean isSchemeChar(char c) {
86 return isAlpha(c) || isDigit(c) || c == '+' || c == '-' || c =='.';
87 }
88
89 private static boolean isValidPercent(String s) {
90 int len = s.length();
91 for (int i = 0; i < len; i++)
92 if (s.charAt(i) == '%') {
93 if (i + 2 >= len)
94 return false;
95 else if (!isHexDigit(s.charAt(i + 1))
96 || !isHexDigit(s.charAt(i + 2)))
97 return false;
98 }
99 return true;
100 }
101
102 private static boolean isValidFragment(String s) {
103 int i = s.indexOf('#');
104 return i < 0 || s.indexOf('#', i + 1) < 0;
105 }
106
107 private static boolean isValidScheme(String s) {
108 if (!isAbsolute(s))
109 return true;
110 int i = s.indexOf(':');
111 if (i == 0
112 || i + 1 == s.length()
113 || !isAlpha(s.charAt(0)))
114 return false;
115 while (--i > 0)
116 if (!isSchemeChar(s.charAt(i)))
117 return false;
118 return true;
119 }
120
121 public static String resolve(String baseUri, String uriReference) {
122 if (!isAbsolute(uriReference) && baseUri != null && isAbsolute(baseUri)) {
123 try {
124 return new URL (new URL (baseUri), uriReference).toString();
125 }
126 catch (MalformedURLException e) { }
127 }
128 return uriReference;
129 }
130
131 public static boolean hasFragmentId(String uri) {
132 return uri.indexOf('#') >= 0;
133 }
134
135 public static boolean isAbsolute(String uri) {
136 int i = uri.indexOf(':');
137 if (i < 0)
138 return false;
139 while (--i >= 0) {
140 switch (uri.charAt(i)) {
141 case '#':
142 case '/':
143 case '?':
144 return false;
145 }
146 }
147 return true;
148 }
149 }
150 |
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