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1
29 package jegg.impl;
30
31 import java.io.File  ;
32 import java.io.FileInputStream ;
33 import java.io.FileNotFoundException ;
34 import java.io.IOException ;
35 import java.io.InputStream ;
36 import java.util.HashMap ;
37 import java.util.Iterator ;
38 import java.util.Map ;
39 import java.util.Properties ;
40
41 import javax.xml.parsers.ParserConfigurationException ;
42
43
44
45 import org.apache.commons.logging.Log;
46 import org.apache.commons.logging.LogFactory;
47 import org.xml.sax.Attributes ;
48 import org.xml.sax.InputSource ;
49 import org.xml.sax.SAXException ;
50 import org.xml.sax.SAXParseException ;
51 import org.xml.sax.helpers.DefaultHandler ;
52
53
58 public class AppXMLContentHandler extends DefaultHandler
59 {
60 private static final Log LOG = LogFactory.getLog(AppXMLContentHandler.class);
61
62 private static final String BASKET = "basket";
64 private static final String EGG = "egg";
65 private static final String USES = "uses";
66 private static final String INCLUDE = "include";
67 private static final String VAR = "var";
68 private static final String PROPERTY = "property";
69
70 private static final String NAME = "name";
72 private static final String HANDLER = "handler";
73 private static final String LOAD = "load";
74 private static final String VALUE = "value";
75
76 private static final String EARLY = "early";
78 private static final String LATE = "late";
79
80 private Map _environment;
81 private boolean _resolve;
82
83 private String _currentDispatcherName;
84 private EggInfo _currentEgg;
85 private String _currentInclude;
86 private Map _currentVars = new HashMap ();
87
88 public AppXMLContentHandler(final Map vars, final boolean resolve)
89 {
90 if (null != vars)
91 {
92 _environment = new HashMap ();
93 _environment.putAll(vars);
94 }
95 _resolve = resolve;
96 }
97
98 public void warn(SAXParseException e)
99 {
100 LOG.warn(e);
101 }
102
103 public void error(SAXParseException e)
104 {
105 LOG.error(e);
106 }
107
108 public void fatalError(SAXParseException e)
109 {
110 LOG.fatal(e);
111 }
112
113 public void startDocument() throws SAXException
114 {
115 try
116 {
117 HenHouse.getHenHouse().hatch("root-port-registry", "jegg.impl.PortRegistry", null, true, false);
118 }
119 catch (HatchException e)
120 {
121 throw new SAXException ("unable to create root port registry");
122 }
123 }
124
125 public void startElement(String uri, String localName, String qName, Attributes attributes)
126 throws SAXException
127 {
128 if (LOG.isDebugEnabled())
129 LOG.debug("startElement (qName=" + qName+")");
130
131 if (qName.equals(BASKET))
132 {
133 String name = attributes.getValue(NAME);
136 if (null != name)
137 _currentDispatcherName = expand(name,_environment);
138 else
139 _currentDispatcherName = null;
140
141 if (LOG.isDebugEnabled())
142 LOG.debug("CurrentDispatcher: " + _currentDispatcherName);
143 _currentEgg = null;
144 }
145 else
146 if (qName.equals(EGG))
147 {
148 String name = attributes.getValue(NAME);
149 String expandedName = expand(name,_environment);
150 String handlerName = attributes.getValue(HANDLER);
151 String handler = expand(handlerName,_environment);
152 String load = attributes.getValue(LOAD);
153 load = (null == load) ? EARLY : load;
154
155 if (!load.equalsIgnoreCase(EARLY) &&
156 !load.equalsIgnoreCase(LATE))
157 {
158 throw new SAXException ("Invalid 'load' attribute: " +load);
159 }
160
161 if (LOG.isDebugEnabled())
162 LOG.debug("Creating egg "+expandedName);
163
164 _currentEgg = new EggInfo(
165 expandedName,
166 handler,
167 _currentDispatcherName,
168 (null==load) ? false : load.equalsIgnoreCase(EARLY));
169
170 HenHouse hh = HenHouse.getHenHouse();
171 hh.add(_currentEgg);
172 }
173 else
174 if (qName.equals(USES))
175 {
176 String name = attributes.getValue(NAME);
177 String expandedName = expand(name,_environment);
178 if (LOG.isDebugEnabled())
179 LOG.debug(_currentEgg.getEggName()+" uses "+expandedName);
180 _currentEgg.addDependency(expandedName);
181 }
182 else
183 if (qName.equals(PROPERTY))
184 {
185 String propName = attributes.getValue(NAME);
186 String expandedPropName = expand(propName,_environment);
187 String propValue = attributes.getValue(VALUE);
188 String expandedPropValue = expand(propValue,_environment);
189 if (LOG.isDebugEnabled())
190 LOG.debug("Environment setting: " + expandedPropName+"="+expandedPropValue);
191 _currentEgg.addProperty(expandedPropName, expandedPropValue);
192 }
193 else
194 if (qName.equals(INCLUDE))
195 {
196 String name = attributes.getValue(NAME);
197 _currentInclude = expand(name,_environment);
198 if (LOG.isDebugEnabled())
199 LOG.debug("Include name: " +_currentInclude);
200 _currentVars.clear();
201 if (null != _environment)
202 _currentVars.putAll(_environment);
203 }
204 else if (qName.equals(VAR))
205 {
206 String varName = attributes.getValue(NAME);
207 String expandedVarName = expand(varName,_environment);
208 String varValue = attributes.getValue(VALUE);
209 String expandedVarValue = expand(varValue,_environment);
210 if (LOG.isDebugEnabled())
211 LOG.debug("Environment setting: " + expandedVarName+"="+expandedVarValue);
212 _currentVars.put(expandedVarName,expandedVarValue);
213 }
214 }
215
216 public void endElement(String uri, String localName, String qName) throws SAXException
217 {
218 if (LOG.isDebugEnabled())
219 LOG.debug("endElement (qName=" + qName+")");
220
221 if (qName.equals(EGG))
222 {
223 if (_currentEgg.shouldBindEarly())
224 {
225 try
226 {
227 HenHouse.getHenHouse().hatch(_currentEgg, false, false);
229 }
230 catch (HatchException e)
231 {
232 throw new SAXException (e);
233 }
234 }
235 }
236 else
237 if (qName.equals(INCLUDE))
238 {
239 InputSource in = null;
240
241 File xml = new File (_currentInclude);
242 if (xml.exists() && xml.canRead())
243 {
244 try
245 {
246 FileInputStream fis = new FileInputStream (xml);
247 in = new InputSource (fis);
248 }
249 catch (FileNotFoundException e)
250 {
251 throw new SAXException (e);
252 }
253 }
254 else
255 {
256 ClassLoader cl = ClassLoader.getSystemClassLoader();
258 InputStream is = cl.getResourceAsStream(_currentInclude);
259 if (null != is)
260 in = new InputSource (is);
261 }
262 if (null != in)
263 {
264 if (LOG.isDebugEnabled())
265 LOG.debug("Loading "+_currentInclude);
266 try { AppRunner.load(in,_currentVars, false); }
267 catch (IOException e) {LOG.error(e); throw new SAXException (e);}
268 catch (ParserConfigurationException e) {LOG.error(e); throw new SAXException (e);}
269 }
270 }
271 }
272
273 public void endDocument() throws SAXException
274 {
275 if (!_resolve) {return;}
276
277 HenHouse henHouse = HenHouse.getHenHouse();
278 for (Iterator it = henHouse.iterator(); it.hasNext(); )
279 {
280 EggInfo info = (EggInfo) it.next();
281 if (info.shouldBindEarly())
282 {
283 try
284 {
285 henHouse.hatch(info,true, false);
286 }
287 catch (HatchException e)
288 {
289 throw new SAXException (e);
290 }
291 }
292 }
293
294 for (Iterator it = Dispatcher.iterator(); it.hasNext(); )
296 {
297 Dispatcher d = (Dispatcher) it.next();
298 if (!d.isAlive())
299 d.start();
300 }
301 }
302
303 private static final String BEGIN_TOKEN = "${";
304 private static final String END_TOKEN = "}";
305
306 String expand(String raw, Map env)
307 {
308 if (null == raw) {return null;}
309
310 StringBuffer buf = null;
311 int pos = 0;
312 while(true)
313 {
314 int newpos = raw.indexOf(BEGIN_TOKEN, pos);
315 if (0 > newpos) {break;}
316 int end = raw.indexOf(END_TOKEN,newpos+BEGIN_TOKEN.length());
317 if (0 > end) {break;}
318 if (null == buf) {buf = new StringBuffer ();}
319 buf.append(raw.substring(pos,newpos));
320 newpos += BEGIN_TOKEN.length();
321 String key = raw.substring(newpos,end);
322 if (null != env)
323 {
324 String val = (String ) env.get(key);
325 if (null != val)
326 buf.append(val);
327 }
328 pos = end+1;
329 if (pos >= raw.length()) {break;}
330 }
331
332 if (null != buf)
333 {
334 if (pos < raw.length())
335 {
336 buf.append(raw.substring(pos));
337 }
338 }
339 return (null == buf) ? raw : buf.toString();
340 }
341 }
342 |
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