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1 package org.sapia.soto.state;
2
3 import org.sapia.soto.Debug;
4 import org.sapia.soto.state.config.Globals;
5
6 import org.sapia.util.xml.confix.ConfigurationException;
7 import org.sapia.util.xml.confix.ObjectHandlerIF;
8
9 import java.util.Iterator  ;
10
11
12
23 public class StateMachine implements ObjectHandlerIF {
24 private static final int TYPE_PRE = 0;
25 private static final int TYPE_POST = 1;
26 private static final int TYPE_ERR = 2;
27 private StaticContext _stmContext = new StaticContext();
28 private boolean _init;
29
30 public StateMachine() {
31 }
32
33
40 public State getState(String id) {
41 StateHolder sh = (StateHolder) _stmContext.getStates().get(id);
42
43 if (sh == null) {
44 return null;
45 }
46
47 return sh.getState();
48 }
49
50
56 public void addState(State state) throws ConfigurationException {
57 addStateHolder(new StateHolder(state));
58 }
59
60
66 public void addModule(Module mod) throws ConfigurationException {
67 if (_init) {
68 throw new IllegalStateException (
69 "Modules must be added prior to initialization");
70 }
71
72 if (mod.getName() != null) {
73 if (_stmContext.getModules().get(mod.getName()) != null) {
74 throw new ConfigurationException("Module already exists for: " +
75 mod.getName());
76 }
77
78 if (mod.getStateMachine(false) != null) {
79 mod.getStateMachine(false)._stmContext.setParent(this);
80 }
81
82 _stmContext.getModules().put(mod.getName(), mod);
83 } else {
84 if (mod.getStateMachine(false) != null) {
85 mod.getStateMachine(false)._stmContext.setParent(this);
86 }
87
88 _stmContext.getAnonymousModules().add(mod);
89 }
90 }
91
92
95 public void addGlobals(Globals gb) {
96 _stmContext._globals.merge(gb);
97 }
98
99
104 public void addStateExecListener(StateExecListener listener) {
105 _stmContext._listeners.add(listener);
106 }
107
108
117 public void merge(StateMachine machine) throws ConfigurationException {
118 Iterator itr = machine._stmContext._states.values().iterator();
119
120 while (itr.hasNext()) {
121 addStateHolder((StateHolder) itr.next());
122 }
123
124 itr = machine._stmContext._modules.values().iterator();
125
126 while (itr.hasNext()) {
127 addModule((Module) itr.next());
128 }
129
130 _stmContext._globals.merge(machine._stmContext._globals);
131 }
132
133
136 public void init() {
137 String id;
138 Iterator itr = _stmContext._states.keySet().iterator();
139 StateHolder sh;
140 State st;
141
142 while (itr.hasNext()) {
143 id = (String ) itr.next();
144 sh = (StateHolder) _stmContext._states.get(id);
145 st = sh.getState();
146 st = _stmContext._globals.applySteps(st);
147 sh.setState(st);
148 sh.setVisible(_stmContext._globals.applyRestriction(st));
149 }
150
151 itr = _stmContext._modules.values().iterator();
152
153 Module mod;
154
155 while (itr.hasNext()) {
156 mod = (Module) itr.next();
157
158 if (mod.getStateMachine(false) == null) {
159 throw new IllegalStateException (
160 "State machine instance not specified for module: " + mod.getName());
161 }
162
163 if (mod.isInheritGlobals() &&
164 (mod.getStateMachine(false)._stmContext._globals != null)) {
165 mod.getStateMachine(false)._stmContext._globals.setParent(_stmContext._globals);
166 }
167
168 if (mod.isInheritModules()) {
169 mod.getStateMachine(false)._stmContext._inheritModules = true;
170 }
171
172 mod.getStateMachine(false).init();
173 }
174 _stmContext.init();
175
176 _init = true;
177 }
178
179
191 public Result execute(String stateId, Context ctx)
192 throws UnknownStateException, StateExecException {
193 return doExecute(stateId, null, ctx, true);
194 }
195
196
209 public Result execute(String stateId, String module, Context ctx)
210 throws UnknownStateException, StateExecException {
211 return doExecute(stateId, module, ctx, true);
212 }
213
214 StaticContext getStmContext() {
215 return _stmContext;
216 }
217
218 protected void addStateHolder(StateHolder sh) throws ConfigurationException {
219 if (sh.getState().getId() != null) {
220 if (_stmContext._states.get(sh.getState().getId()) != null) {
221 throw new ConfigurationException("State already exists for: " +
222 sh.getState().getId());
223 }
224
225 _stmContext._states.put(sh.getState().getId(), sh);
226 } else {
227 throw new ConfigurationException("'id' attribute not specified on state");
228 }
229 }
230
231 private Module getModule(String name) {
232 Module mod = (Module) _stmContext._modules.get(name);
233
234 if (_stmContext._inheritModules && (_stmContext._parent != null)) {
235 mod = _stmContext._parent.getModule(name);
236 }
237
238 return mod;
239 }
240
241 private Result doExecute(String stateId, String module, Context ctx,
242 boolean fromOutside) throws UnknownStateException, StateExecException {
243 if (!_init) {
244 throw new IllegalStateException (
245 "State machine not initialized; call init() prior to using it.");
246 }
247
248 if (stateId == null) {
249 throw new IllegalArgumentException ("State id cannot be null");
250 }
251
252 if (module != null) {
253 if (Debug.DEBUG) {
254 Debug.debug("Executing state in module: " + module);
255 }
256
257 Module mod = getModule(module);
258
259 if (mod == null) {
260 throw new IllegalArgumentException ("Module does not exist: " + module);
261 }
262
263 StateMachine stm = mod.getStateMachine(true);
264
265 return stm.doExecute(stateId, null, ctx, fromOutside);
266 }
267
268 Result rs = new Result(this, ctx);
269 rs.setNextStateId(stateId);
270
271 StateHolder sh;
272 State st;
273 int count = 0;
274
275 while ((rs.getNextStateId() != null) && !rs.isError() && !rs.isAborted()) {
276 sh = (StateHolder) _stmContext.getStateFor(rs.getNextStateId());
277
278 if (sh == null) {
279 throw new UnknownStateException(rs.getNextStateId());
280 }
281
282 st = sh.getState();
283
284 if ((count == 0) && fromOutside && !sh.isVisible()) {
285 throw new StateAccessException("State '" + st.getId() +
286 "' cannot be executed by client application");
287 }
288
289 rs.setCurrentStateId(rs.getNextStateId());
290 rs.reset();
291 notifyListeners(st, rs, TYPE_PRE);
292
293 if (Debug.DEBUG) {
294 Debug.debug("Executing: " + st.getId() + " (" +
295 st.getClass().getName() + ")");
296 }
297
298 st.execute(rs);
299
300 if (rs.isError()) {
301 notifyListeners(st, rs, TYPE_ERR);
302 } else {
303 notifyListeners(st, rs, TYPE_POST);
304 }
305
306 count++;
307 }
308
309 if (rs.isError() && !rs.isErrorHandled()) {
310 if ((rs.getError().getThrowable() != null) &&
311 rs.getError().getThrowable() instanceof StateExecException) {
312 throw (StateExecException) rs.getError().getThrowable();
313 }
314
315 throw new StateExecException(rs.getError());
316 }
317
318 return rs;
319 }
320
321 void execute(String stateId, String module, Result rs)
322 throws StateExecException {
323 doExecute(stateId, module, rs.getContext(), false);
324 }
325
326 private void notifyListeners(State f, Result st, int type) {
327 StateExecListener listener;
328
329 for (int i = 0; i < _stmContext._listeners.size(); i++) {
330 listener = (StateExecListener) _stmContext._listeners.get(i);
331
332 if (type == TYPE_PRE) {
333 listener.onPreExec(st, f.getId());
334 } else if (type == TYPE_POST) {
335 listener.onPostExec(st, f.getId());
336 } else {
337 listener.onError(st, f.getId(), st.getError());
338 }
339 }
340 }
341
342
345 public void handleObject(String name, Object obj)
346 throws ConfigurationException {
347 if (obj instanceof State) {
348 State state = (State) obj;
349 addState(state);
350 } else if (obj instanceof Globals) {
351 _stmContext._globals.merge((Globals) obj);
352 } else if (obj instanceof Module) {
353 addModule((Module) obj);
354 }
355 }
356 }
357 |
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