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1
16
19
20 package org.apache.xalan.xsltc.compiler;
21
22 import java.util.Enumeration  ;
23 import java.util.Vector ;
24
25 import org.apache.bcel.generic.ConstantPoolGen;
26 import org.apache.bcel.generic.INVOKESPECIAL;
27 import org.apache.bcel.generic.INVOKEVIRTUAL;
28 import org.apache.bcel.generic.Instruction;
29 import org.apache.bcel.generic.InstructionList;
30 import org.apache.bcel.generic.NEW;
31 import org.apache.xalan.xsltc.compiler.util.ClassGenerator;
32 import org.apache.xalan.xsltc.compiler.util.ErrorMsg;
33 import org.apache.xalan.xsltc.compiler.util.MethodGenerator;
34 import org.apache.xalan.xsltc.compiler.util.Type;
35 import org.apache.xalan.xsltc.compiler.util.TypeCheckError;
36
37
41 final class AttributeValueTemplate extends AttributeValue {
42
43 public AttributeValueTemplate(String value, Parser parser,
44 SyntaxTreeNode parent)
45 {
46 setParent(parent);
47 setParser(parser);
48 if (check(value, parser)) {
49 parseAVTemplate(0, value, parser);
50 }
51 }
52
53 private void parseAVTemplate(final int start, String text, Parser parser) {
54 String str;
55
56 if (text == null) return;
57
58 int open = start - 2;
60 do {
61 open = text.indexOf('{', open+2);
62 } while ((open != -1) &&
63 (open < (text.length()-1)) &&
64 (text.charAt(open+1) == '{'));
65
66 if (open != -1) {
67 int close = open - 2;
69 do {
70 close = text.indexOf('}', close+2);
71 } while ((close != -1) &&
72 (close < (text.length()-1)) &&
73 (text.charAt(close+1) == '}'));
74
75 if (open > start) {
77 str = removeDuplicateBraces(text.substring(start, open));
78 addElement(new LiteralExpr(str));
79 }
80 if (close > open + 1) {
82 str = text.substring(open + 1, close);
83 str = removeDuplicateBraces(text.substring(open+1,close));
84 addElement(parser.parseExpression(this, str));
85 }
86 parseAVTemplate(close + 1, text, parser);
88
89 }
90 else if (start < text.length()) {
91 str = removeDuplicateBraces(text.substring(start));
93 addElement(new LiteralExpr(str));
94 }
95 }
96
97 public String removeDuplicateBraces(String orig) {
98 String result = orig;
99 int index;
100
101 while ((index = result.indexOf("{{")) != -1) {
102 result = result.substring(0,index) +
103 result.substring(index+1,result.length());
104 }
105
106 while ((index = result.indexOf("}}")) != -1) {
107 result = result.substring(0,index) +
108 result.substring(index+1,result.length());
109 }
110
111 return(result);
112 }
113
114 public Type typeCheck(SymbolTable stable) throws TypeCheckError {
115 final Vector contents = getContents();
116 final int n = contents.size();
117 for (int i = 0; i < n; i++) {
118 final Expression exp = (Expression)contents.elementAt(i);
119 if (!exp.typeCheck(stable).identicalTo(Type.String)) {
120 contents.setElementAt(new CastExpr(exp, Type.String), i);
121 }
122 }
123 return _type = Type.String;
124 }
125
126 public String toString() {
127 final StringBuffer buffer = new StringBuffer ("AVT:[");
128 final int count = elementCount();
129 for (int i = 0; i < count; i++) {
130 buffer.append(elementAt(i).toString());
131 if (i < count - 1)
132 buffer.append(' ');
133 }
134 return buffer.append(']').toString();
135 }
136
137 public void translate(ClassGenerator classGen, MethodGenerator methodGen) {
138 if (elementCount() == 1) {
139 final Expression exp = (Expression)elementAt(0);
140 exp.translate(classGen, methodGen);
141 }
142 else {
143 final ConstantPoolGen cpg = classGen.getConstantPool();
144 final InstructionList il = methodGen.getInstructionList();
145 final int initBuffer = cpg.addMethodref(STRING_BUFFER_CLASS,
146 "<init>", "()V");
147 final Instruction append =
148 new INVOKEVIRTUAL(cpg.addMethodref(STRING_BUFFER_CLASS,
149 "append",
150 "(" + STRING_SIG + ")"
151 + STRING_BUFFER_SIG));
152
153 final int toString = cpg.addMethodref(STRING_BUFFER_CLASS,
154 "toString",
155 "()"+STRING_SIG);
156 il.append(new NEW(cpg.addClass(STRING_BUFFER_CLASS)));
157 il.append(DUP);
158 il.append(new INVOKESPECIAL(initBuffer));
159 final Enumeration elements = elements();
161 while (elements.hasMoreElements()) {
162 final Expression exp = (Expression)elements.nextElement();
163 exp.translate(classGen, methodGen);
164 il.append(append);
165 }
166 il.append(new INVOKEVIRTUAL(toString));
167 }
168 }
169
170 private boolean check(String value, Parser parser) {
171 if (value == null) return true;
173
174 final char[] chars = value.toCharArray();
175 int level = 0;
176 for (int i = 0; i < chars.length; i++) {
177 switch (chars[i]) {
178 case '{':
179 if (((i+1) == (chars.length)) || (chars[i+1] != '{'))
180 ++level;
181 else
182 i++;
183 break;
184 case '}':
185 if (((i+1) == (chars.length)) || (chars[i+1] != '}'))
186 --level;
187 else
188 i++;
189 break;
190 default:
191 continue;
192 }
193 switch (level) {
194 case 0:
195 case 1:
196 continue;
197 default:
198 reportError(getParent(), parser,
199 ErrorMsg.ATTR_VAL_TEMPLATE_ERR, value);
200 return false;
201 }
202 }
203 if (level != 0) {
204 reportError(getParent(), parser,
205 ErrorMsg.ATTR_VAL_TEMPLATE_ERR, value);
206 return false;
207 }
208 return true;
209 }
210 }
211 |
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