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1 package net.sf.saxon.functions;
2 import net.sf.saxon.expr.Expression;
3 import net.sf.saxon.expr.StaticContext;
4 import net.sf.saxon.expr.XPathContext;
5 import net.sf.saxon.om.Item;
6 import net.sf.saxon.trans.DynamicError;
7 import net.sf.saxon.trans.XPathException;
8 import net.sf.saxon.type.RegexTranslator;
9 import net.sf.saxon.value.AtomicValue;
10 import net.sf.saxon.value.StringValue;
11 import net.sf.saxon.value.Value;
12
13 import java.util.regex.Pattern  ;
14 import java.util.regex.PatternSyntaxException ;
15 import java.util.regex.Matcher ;
16
17
18
22
23 public class Replace extends SystemFunction {
24
25 private Pattern regexp;
26
27
31
32 public Expression simplify(StaticContext env) throws XPathException {
33 Expression e = simplifyArguments(env);
34
35 if (!(e instanceof Value)) {
37 regexp = Matches.tryToCompile(argument, 1, 3);
38
39 if (regexp != null && regexp.matcher("").matches()) {
41 DynamicError err = new DynamicError(
42 "The regular expression must not be one that matches a zero-length string");
43 err.setErrorCode("FORX0003");
44 throw err;
45 }
46 }
47
48 return e;
49 }
50
51
52
55
56 public Item evaluateItem(XPathContext c) throws XPathException {
57
58 AtomicValue arg0 = (AtomicValue)argument[0].evaluateItem(c);
59 if (arg0==null) {
60 arg0 = StringValue.EMPTY_STRING;
61 }
62
63 AtomicValue arg2 = (AtomicValue)argument[2].evaluateItem(c);
64 CharSequence replacement = arg2.getStringValueCS();
65 checkReplacement(replacement, c);
66
67 Pattern re = regexp;
68 if (re == null) {
69
70 AtomicValue arg1 = (AtomicValue)argument[1].evaluateItem(c);
71
72 CharSequence flags;
73
74 if (argument.length == 3) {
75 flags = "";
76 } else {
77 AtomicValue arg3 = (AtomicValue)argument[3].evaluateItem(c);
78 flags = arg3.getStringValueCS();
79 }
80
81 try {
82 String javaRegex = RegexTranslator.translate(
83 arg1.getStringValueCS(), true);
84 re = Pattern.compile(javaRegex, Matches.setFlags(flags));
85 } catch (RegexTranslator.RegexSyntaxException err) {
86 DynamicError de = new DynamicError(err);
87 de.setErrorCode("FORX0002");
88 de.setXPathContext(c);
89 throw de;
90 } catch (PatternSyntaxException err) {
91 DynamicError de = new DynamicError(err);
92 de.setErrorCode("FORX0002");
93 de.setXPathContext(c);
94 throw de;
95 }
96
97 if (re.matcher("").matches()) {
99 dynamicError(
100 "The regular expression must not be one that matches a zero-length string", "FORX0003", c);
101 }
102 }
103 String input = arg0.getStringValue();
104 Matcher matcher = re.matcher(input);
105 try {
106 String res = matcher.replaceAll(replacement.toString());
107 return StringValue.makeStringValue(res);
108 } catch (IndexOutOfBoundsException e) {
109 int gps = matcher.groupCount();
113 if (gps >= 9) {
114 throw e;
116 }
117 String r = replacement.toString();
118 String f = "\\$[" + (gps+1) + "-9]";
120 String rep = Pattern.compile(f).matcher(r).replaceAll("");
121 String res = matcher.replaceAll(rep);
122 return StringValue.makeStringValue(res);
123 }
124
125 }
126
127
130
131 private void checkReplacement(CharSequence rep, XPathContext context) throws XPathException {
132 for (int i=0; i<rep.length(); i++) {
133 char c = rep.charAt(i);
134 if (c == '$') {
135 if (i+1 < rep.length()) {
136 char next = rep.charAt(++i);
137 if (next < '0' || next > '9') {
138 dynamicError("Invalid replacement string in replace(): $ sign must be followed by digit 0-9",
139 "FORX0004", context);
140 }
141 } else {
142 dynamicError("Invalid replacement string in replace(): $ sign at end of string",
143 "FORX0004", context);
144 }
145 } else if (c == '\\') {
146 if (i+1 < rep.length()) {
147 char next = rep.charAt(++i);
148 if (next != '\\' && next != '$') {
149 dynamicError("Invalid replacement string in replace(): \\ character must be followed by \\ or $",
150 "FORX0004", context);
151 }
152 } else {
153 dynamicError("Invalid replacement string in replace(): \\ character at end of string",
154 "FORX0004", context);
155 }
156 }
157 }
158 }
159
160 }
161
162
163
164 |
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