diff options
Diffstat (limited to 'subprojects/viatra-runtime/src/main/java/tools/refinery/viatra/runtime/internal/engine/ModelUpdateProvider.java')
-rw-r--r-- | subprojects/viatra-runtime/src/main/java/tools/refinery/viatra/runtime/internal/engine/ModelUpdateProvider.java | 214 |
1 files changed, 214 insertions, 0 deletions
diff --git a/subprojects/viatra-runtime/src/main/java/tools/refinery/viatra/runtime/internal/engine/ModelUpdateProvider.java b/subprojects/viatra-runtime/src/main/java/tools/refinery/viatra/runtime/internal/engine/ModelUpdateProvider.java new file mode 100644 index 00000000..1f2c27e8 --- /dev/null +++ b/subprojects/viatra-runtime/src/main/java/tools/refinery/viatra/runtime/internal/engine/ModelUpdateProvider.java | |||
@@ -0,0 +1,214 @@ | |||
1 | /******************************************************************************* | ||
2 | * Copyright (c) 2010-2013, Abel Hegedus, Istvan Rath and Daniel Varro | ||
3 | * This program and the accompanying materials are made available under the | ||
4 | * terms of the Eclipse Public License v. 2.0 which is available at | ||
5 | * http://www.eclipse.org/legal/epl-v20.html. | ||
6 | * | ||
7 | * SPDX-License-Identifier: EPL-2.0 | ||
8 | *******************************************************************************/ | ||
9 | package tools.refinery.viatra.runtime.internal.engine; | ||
10 | |||
11 | import java.util.ArrayList; | ||
12 | import java.util.Collection; | ||
13 | import java.util.Collections; | ||
14 | import java.util.EnumMap; | ||
15 | import java.util.HashSet; | ||
16 | import java.util.Map; | ||
17 | import java.util.Map.Entry; | ||
18 | |||
19 | import org.apache.log4j.Logger; | ||
20 | import tools.refinery.viatra.runtime.api.AdvancedViatraQueryEngine; | ||
21 | import tools.refinery.viatra.runtime.api.IMatchUpdateListener; | ||
22 | import tools.refinery.viatra.runtime.api.IPatternMatch; | ||
23 | import tools.refinery.viatra.runtime.api.ViatraQueryEngineLifecycleListener; | ||
24 | import tools.refinery.viatra.runtime.api.ViatraQueryMatcher; | ||
25 | import tools.refinery.viatra.runtime.api.ViatraQueryModelUpdateListener; | ||
26 | import tools.refinery.viatra.runtime.api.ViatraQueryModelUpdateListener.ChangeLevel; | ||
27 | import tools.refinery.viatra.runtime.api.scope.ViatraBaseIndexChangeListener; | ||
28 | import tools.refinery.viatra.runtime.exception.ViatraQueryException; | ||
29 | import tools.refinery.viatra.runtime.matchers.util.CollectionsFactory; | ||
30 | |||
31 | public final class ModelUpdateProvider extends ListenerContainer<ViatraQueryModelUpdateListener> { | ||
32 | |||
33 | private final AdvancedViatraQueryEngine queryEngine; | ||
34 | private ChangeLevel currentChange = ChangeLevel.NO_CHANGE; | ||
35 | private ChangeLevel maxLevel = ChangeLevel.NO_CHANGE; | ||
36 | private final Map<ChangeLevel, Collection<ViatraQueryModelUpdateListener>> listenerMap; | ||
37 | private final Logger logger; | ||
38 | |||
39 | public ModelUpdateProvider(AdvancedViatraQueryEngine queryEngine, Logger logger) { | ||
40 | super(); | ||
41 | this.queryEngine = queryEngine; | ||
42 | this.logger = logger; | ||
43 | listenerMap = new EnumMap<>(ChangeLevel.class); | ||
44 | } | ||
45 | |||
46 | @Override | ||
47 | protected void listenerAdded(ViatraQueryModelUpdateListener listener) { | ||
48 | // check ChangeLevel | ||
49 | // create callback for given level if required | ||
50 | if(listenerMap.isEmpty()) { | ||
51 | try { | ||
52 | this.queryEngine.getBaseIndex().addBaseIndexChangeListener(indexListener); | ||
53 | // add listener to new matchers (use lifecycle listener) | ||
54 | this.queryEngine.addLifecycleListener(selfListener); | ||
55 | } catch (ViatraQueryException e) { | ||
56 | throw new IllegalStateException("Model update listener used on engine without base index", e); | ||
57 | } | ||
58 | } | ||
59 | |||
60 | ChangeLevel changeLevel = listener.getLevel(); | ||
61 | listenerMap.computeIfAbsent(changeLevel, k -> CollectionsFactory.createSet()).add(listener); | ||
62 | // increase or keep max level of listeners | ||
63 | ChangeLevel oldMaxLevel = maxLevel; | ||
64 | maxLevel = maxLevel.changeOccured(changeLevel); | ||
65 | if(!maxLevel.equals(oldMaxLevel) && ChangeLevel.MATCHSET.compareTo(oldMaxLevel) > 0 && ChangeLevel.MATCHSET.compareTo(maxLevel) <= 0) { | ||
66 | // add matchUpdateListener to all matchers | ||
67 | for (ViatraQueryMatcher<?> matcher : this.queryEngine.getCurrentMatchers()) { | ||
68 | this.queryEngine.addMatchUpdateListener(matcher, matchSetListener, false); | ||
69 | } | ||
70 | } | ||
71 | } | ||
72 | |||
73 | @Override | ||
74 | protected void listenerRemoved(ViatraQueryModelUpdateListener listener) { | ||
75 | ChangeLevel changeLevel = listener.getLevel(); | ||
76 | Collection<ViatraQueryModelUpdateListener> old = listenerMap.getOrDefault(changeLevel, Collections.emptySet()); | ||
77 | boolean removed = old.remove(listener); | ||
78 | if(removed) { | ||
79 | if (old.isEmpty()) listenerMap.remove(changeLevel); | ||
80 | } else { | ||
81 | handleUnsuccesfulRemove(listener); | ||
82 | } | ||
83 | |||
84 | updateMaxLevel(); | ||
85 | |||
86 | if(listenerMap.isEmpty()) { | ||
87 | this.queryEngine.removeLifecycleListener(selfListener); | ||
88 | removeBaseIndexChangeListener(); | ||
89 | } | ||
90 | } | ||
91 | |||
92 | private void removeBaseIndexChangeListener() { | ||
93 | try { | ||
94 | this.queryEngine.getBaseIndex().removeBaseIndexChangeListener(indexListener); | ||
95 | } catch (ViatraQueryException e) { | ||
96 | throw new IllegalStateException("Model update listener used on engine without base index", e); | ||
97 | } | ||
98 | } | ||
99 | |||
100 | private void updateMaxLevel() { | ||
101 | if(!listenerMap.containsKey(maxLevel)) { | ||
102 | ChangeLevel newMaxLevel = ChangeLevel.NO_CHANGE; | ||
103 | for (ChangeLevel level : new HashSet<>(listenerMap.keySet())) { | ||
104 | newMaxLevel = newMaxLevel.changeOccured(level); | ||
105 | } | ||
106 | maxLevel = newMaxLevel; | ||
107 | } | ||
108 | if(maxLevel.compareTo(ChangeLevel.MATCHSET) < 0) { | ||
109 | // remove listener from matchers | ||
110 | for (ViatraQueryMatcher<?> matcher : this.queryEngine.getCurrentMatchers()) { | ||
111 | this.queryEngine.removeMatchUpdateListener(matcher, matchSetListener); | ||
112 | } | ||
113 | } | ||
114 | } | ||
115 | |||
116 | private void handleUnsuccesfulRemove(ViatraQueryModelUpdateListener listener) { | ||
117 | for (Entry<ChangeLevel, Collection<ViatraQueryModelUpdateListener>> entry : listenerMap.entrySet()) { | ||
118 | Collection<ViatraQueryModelUpdateListener> existingListeners = entry.getValue(); | ||
119 | // if the listener is contained in some other bucket, remove it from there | ||
120 | if(existingListeners.remove(listener)) { | ||
121 | logger.error("Listener "+listener+" change level changed since initialization!"); | ||
122 | if (existingListeners.isEmpty()) listenerMap.remove(entry.getKey()); | ||
123 | return; // listener is contained only once | ||
124 | } | ||
125 | } | ||
126 | logger.error("Listener "+listener+" already removed from map (e.g. engine was already disposed)!"); | ||
127 | } | ||
128 | |||
129 | private void notifyListeners() { | ||
130 | |||
131 | // any change that occurs after this point should be regarded as a new event | ||
132 | // FIXME what should happen when a listener creates new notifications? | ||
133 | // -> other listeners will get events in different order | ||
134 | ChangeLevel tempLevel = currentChange; | ||
135 | currentChange = ChangeLevel.NO_CHANGE; | ||
136 | |||
137 | if(!listenerMap.isEmpty()) { | ||
138 | for (ChangeLevel level : new HashSet<>(listenerMap.keySet())) { | ||
139 | if(tempLevel.compareTo(level) >= 0) { | ||
140 | for (ViatraQueryModelUpdateListener listener : new ArrayList<>(listenerMap.get(level))) { | ||
141 | try { | ||
142 | listener.notifyChanged(tempLevel); | ||
143 | } catch (Exception ex) { | ||
144 | logger.error( | ||
145 | "VIATRA Query encountered an error in delivering model update notification to listener " | ||
146 | + listener + ".", ex); | ||
147 | } | ||
148 | } | ||
149 | } | ||
150 | } | ||
151 | } else { | ||
152 | throw new IllegalStateException("Notify listeners must not be called without listeners! Maybe an update callback was not removed correctly."); | ||
153 | } | ||
154 | |||
155 | } | ||
156 | |||
157 | // model update "providers": | ||
158 | // - model: IQBase callback even if not dirty | ||
159 | // - index: IQBase dirty callback | ||
160 | private final ViatraBaseIndexChangeListener indexListener = new ViatraBaseIndexChangeListener() { | ||
161 | |||
162 | @Override | ||
163 | public boolean onlyOnIndexChange() { | ||
164 | return false; | ||
165 | } | ||
166 | |||
167 | @Override | ||
168 | public void notifyChanged(boolean indexChanged) { | ||
169 | if(indexChanged) { | ||
170 | currentChange = currentChange.changeOccured(ChangeLevel.INDEX); | ||
171 | } else { | ||
172 | currentChange = currentChange.changeOccured(ChangeLevel.MODEL); | ||
173 | } | ||
174 | notifyListeners(); | ||
175 | } | ||
176 | |||
177 | }; | ||
178 | // - matchset: add the same listener to each matcher and use a dirty flag. needs IQBase callback as well | ||
179 | private final IMatchUpdateListener<IPatternMatch> matchSetListener = new IMatchUpdateListener<IPatternMatch>() { | ||
180 | |||
181 | @Override | ||
182 | public void notifyDisappearance(IPatternMatch match) { | ||
183 | currentChange = currentChange.changeOccured(ChangeLevel.MATCHSET); | ||
184 | } | ||
185 | |||
186 | @Override | ||
187 | public void notifyAppearance(IPatternMatch match) { | ||
188 | currentChange = currentChange.changeOccured(ChangeLevel.MATCHSET); | ||
189 | } | ||
190 | }; | ||
191 | |||
192 | private final ViatraQueryEngineLifecycleListener selfListener = new ViatraQueryEngineLifecycleListener() { | ||
193 | |||
194 | @Override | ||
195 | public void matcherInstantiated(ViatraQueryMatcher<? extends IPatternMatch> matcher) { | ||
196 | if (maxLevel.compareTo(ChangeLevel.MATCHSET) >= 0) { | ||
197 | ModelUpdateProvider.this.queryEngine.addMatchUpdateListener(matcher, matchSetListener, false); | ||
198 | } | ||
199 | } | ||
200 | |||
201 | @Override | ||
202 | public void engineWiped() {} | ||
203 | |||
204 | @Override | ||
205 | public void engineDisposed() { | ||
206 | removeBaseIndexChangeListener(); | ||
207 | listenerMap.clear(); | ||
208 | maxLevel = ChangeLevel.NO_CHANGE; | ||
209 | } | ||
210 | |||
211 | @Override | ||
212 | public void engineBecameTainted(String description, Throwable t) {} | ||
213 | }; | ||
214 | } | ||