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1
8
9 package mx4j.loading;
10
11 import java.lang.reflect.Constructor  ;
12 import java.util.ArrayList ;
13 import java.util.List ;
14
15 import javax.management.MalformedObjectNameException ;
16 import javax.management.ObjectName ;
17 import javax.management.loading.MLet ;
18
19
27 public class MLetParser
28 {
29 public static final String OPEN_COMMENT = "<!--";
30 public static final String CLOSE_COMMENT = "-->";
31
32 public static final String OPEN_BRACKET = "<";
33 public static final String CLOSE_BRACKET = ">";
34
35 public static final String MLET_TAG = "MLET";
36 public static final String CODE_ATTR = "CODE";
37 public static final String OBJECT_ATTR = "OBJECT";
38 public static final String ARCHIVE_ATTR = "ARCHIVE";
39 public static final String CODEBASE_ATTR = "CODEBASE";
40 public static final String NAME_ATTR = "NAME";
41 public static final String VERSION_ATTR = "VERSION";
42
43 public static final String ARG_TAG = "ARG";
44 public static final String TYPE_ATTR = "TYPE";
45 public static final String VALUE_ATTR = "VALUE";
46
47 private MLet mlet;
48
49
52 public MLetParser()
53 {
54 }
55
56
60 public MLetParser(MLet mlet)
61 {
62 this.mlet = mlet;
63 }
64
65
72 public List parse(String content) throws MLetParseException
73 {
74 if (content == null) throw new MLetParseException("MLet file content cannot be null");
75
76 content = stripComments(content.trim());
78 content = convertToUpperCase(content);
79
80 ArrayList mlets = parseMLets(content);
81 if (mlets.size() < 1) throw new MLetParseException("MLet file is empty");
82
83 ArrayList mletTags = new ArrayList ();
84 for (int i = 0; i < mlets.size(); ++i)
85 {
86 String mletTag = (String )mlets.get(i);
87
88 MLetTag tag = parseMLet(mletTag);
89 mletTags.add(tag);
90 }
91
92 return mletTags;
93 }
94
95 private MLetTag parseMLet(String content) throws MLetParseException
96 {
97 MLetTag tag = new MLetTag();
98 parseMLetAttributes(tag, content);
99 parseMLetArguments(tag, content);
100 return tag;
101 }
102
103 private ArrayList parseMLets(String content) throws MLetParseException
104 {
105 ArrayList list = new ArrayList ();
106 int start = 0;
107 int current = -1;
108 while ((current = findOpenTag(content, start, MLET_TAG)) >= 0)
109 {
110 int end = findCloseTag(content, current + 1, MLET_TAG, true);
111 if (end < 0) throw new MLetParseException("MLET tag not closed at index: " + current);
112
113 String mlet = content.substring(current, end);
114 list.add(mlet);
115
116 start = end + 1;
117 }
118 return list;
119 }
120
121 private void parseMLetArguments(MLetTag tag, String content) throws MLetParseException
122 {
123 int start = 0;
124 int current = -1;
125 while ((current = findOpenTag(content, start, ARG_TAG)) >= 0)
126 {
127 int end = findCloseTag(content, current + 1, ARG_TAG, false);
128 if (end < 0) throw new MLetParseException("ARG tag not closed");
129
130 String arg = content.substring(current, end);
131
132 int type = arg.indexOf(TYPE_ATTR);
133 if (type < 0) throw new MLetParseException("Missing TYPE attribute");
134
135 int value = arg.indexOf(VALUE_ATTR);
136 if (value < 0) throw new MLetParseException("Missing VALUE attribute");
137
138 String className = findAttributeValue(arg, type, TYPE_ATTR);
139 tag.addArg(className, convertToObject(className, findAttributeValue(arg, value, VALUE_ATTR)));
140
141 start = end + 1;
142 }
143 }
144
145 private void parseMLetAttributes(MLetTag tag, String content) throws MLetParseException
146 {
147 int end = content.indexOf(CLOSE_BRACKET);
148 String attributes = content.substring(0, end);
149
150 int archive = -1;
152 int object = -1;
153 int code = -1;
154
155 archive = attributes.indexOf(ARCHIVE_ATTR);
156 if (archive < 0) throw new MLetParseException("Missing ARCHIVE attribute");
157
158 code = attributes.indexOf(CODE_ATTR);
159 object = attributes.indexOf(OBJECT_ATTR);
160 if (code < 0 && object < 0) throw new MLetParseException("Missing CODE or OBJECT attribute");
161 if (code > 0 && object > 0) throw new MLetParseException("CODE and OBJECT attributes cannot be both present");
162
163 if (code >= 0)
164 tag.setCode(findAttributeValue(attributes, code, CODE_ATTR));
165 else
166 tag.setObject(findAttributeValue(attributes, object, OBJECT_ATTR));
167
168 tag.setArchive(findAttributeValue(attributes, archive, ARCHIVE_ATTR));
169
170 int codebase = attributes.indexOf(CODEBASE_ATTR);
172 if (codebase >= 0) tag.setCodeBase(findAttributeValue(attributes, codebase, CODEBASE_ATTR));
173
174 int name = attributes.indexOf(NAME_ATTR);
175 if (name >= 0)
176 {
177 String objectName = findAttributeValue(attributes, name, NAME_ATTR);
178 try
179 {
180 tag.setName(new ObjectName (objectName));
181 }
182 catch (MalformedObjectNameException x)
183 {
184 throw new MLetParseException("Invalid ObjectName: " + objectName);
185 }
186 }
187
188 int version = attributes.indexOf(VERSION_ATTR);
189 if (version >= 0) tag.setVersion(findAttributeValue(attributes, version, VERSION_ATTR));
190 }
191
192 private String findAttributeValue(String content, int start, String attribute) throws MLetParseException
193 {
194 int equal = content.indexOf('=', start);
195 if (equal < 0) throw new MLetParseException("Missing '=' for attribute");
196
197 if (!attribute.equals(content.substring(start, equal).trim())) throw new MLetParseException("Invalid attribute");
199
200 int begin = content.indexOf('"', equal + 1);
201 if (begin < 0) throw new MLetParseException("Missing quotes for attribute value");
202
203 if (content.substring(equal + 1, begin).trim().length() != 0) throw new MLetParseException("Invalid attribute value");
205
206 int end = content.indexOf('"', begin + 1);
207 if (end < 0) throw new MLetParseException("Missing quote for attribute value");
208
209 return content.substring(begin + 1, end).trim();
210 }
211
212 private int findOpenTag(String content, int start, String tag)
213 {
214 String opening = new StringBuffer (OPEN_BRACKET).append(tag).toString();
215 return content.indexOf(opening, start);
216 }
217
218 private int findCloseTag(String content, int start, String tag, boolean strictSyntax)
219 {
220 int count = 1;
221
222 do
223 {
224 int close = content.indexOf(CLOSE_BRACKET, start);
225 if (close < 0)
226 {
227 return -1;
228 }
229 int open = content.indexOf(OPEN_BRACKET, start);
230 if (open >= 0 && close > open)
231 {
232 ++count;
233 }
234 else
235 {
236 --count;
237 if (count == 0)
238 {
239 if (!strictSyntax || (strictSyntax && content.charAt(close - 1) == '/'))
242 {
243 return close + 1;
245 }
246 else
247 {
248 String closing = new StringBuffer (OPEN_BRACKET).append("/").append(tag).append(CLOSE_BRACKET).toString();
250 close = content.indexOf(closing, start);
251 if (close < 0)
252 return -1;
253 else
254 return close + closing.length();
255 }
256 }
257 }
258
259 start = close + 1;
260 }
261 while (true);
262 }
263
264 private String stripComments(String content) throws MLetParseException
265 {
266 StringBuffer buffer = new StringBuffer ();
267 int start = 0;
268 int current = -1;
269 while ((current = content.indexOf(OPEN_COMMENT, start)) >= 0)
270 {
271 int end = content.indexOf(CLOSE_COMMENT, current + 1);
272
273 if (end < 0) throw new MLetParseException("Missing close comment tag at index: " + current);
274
275 String stripped = content.substring(start, current);
276 buffer.append(stripped);
277 start = end + CLOSE_COMMENT.length();
278 }
279 String stripped = content.substring(start, content.length());
280 buffer.append(stripped);
281 return buffer.toString();
282 }
283
284 private String convertToUpperCase(String content) throws MLetParseException
285 {
286 StringBuffer buffer = new StringBuffer ();
287 int start = 0;
288 int current = -1;
289 while ((current = content.indexOf("\"", start)) >= 0)
290 {
291 int end = content.indexOf("\"", current + 1);
292
293 if (end < 0) throw new MLetParseException("Missing closing quote at index: " + current);
294
295 String converted = content.substring(start, current).toUpperCase();
296 buffer.append(converted);
297 String quoted = content.substring(current, end + 1);
298 buffer.append(quoted);
299 start = end + 1;
300 }
301 String converted = content.substring(start, content.length()).toUpperCase();
302 buffer.append(converted);
303 return buffer.toString();
304 }
305
306 private Object convertToObject(String clsName, String value) throws MLetParseException
307 {
308 try
309 {
310 if (clsName.equals("boolean") || clsName.equals("java.lang.Boolean"))
311 return Boolean.valueOf(value);
312 else if (clsName.equals("byte") || clsName.equals("java.lang.Byte"))
313 return Byte.valueOf(value);
314 else if (clsName.equals("char") || clsName.equals("java.lang.Character"))
315 {
316 char ch = 0;
317 if (value.length() > 0) ch = value.charAt(0);
318 return new Character (ch);
319 }
320 else if (clsName.equals("short") || clsName.equals("java.lang.Short"))
321 return Short.valueOf(value);
322 else if (clsName.equals("int") || clsName.equals("java.lang.Integer"))
323 return Integer.valueOf(value);
324 else if (clsName.equals("long") || clsName.equals("java.lang.Long"))
325 return Long.valueOf(value);
326 else if (clsName.equals("float") || clsName.equals("java.lang.Float"))
327 return Float.valueOf(value);
328 else if (clsName.equals("double") || clsName.equals("java.lang.Double"))
329 return Double.valueOf(value);
330 else if (clsName.equals("java.lang.String"))
331 return value;
332 else if (mlet != null)
333 {
334 try
335 {
336 Class cls = mlet.loadClass(clsName);
337 Constructor ctor = cls.getConstructor(new Class []{String .class});
338 return ctor.newInstance(new Object []{value});
339 }
340 catch (Exception ignored)
341 {
342 }
343 }
344 }
345 catch (NumberFormatException x)
346 {
347 throw new MLetParseException("Invalid value: " + value);
348 }
349 return null;
350 }
351 }
352 |
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