bundles/org.simantics.db.impl/src/org/simantics/db/impl/query/QueryListening.java

   1 package org.simantics.db.impl.query;
   2
   3 import java.io.BufferedOutputStream;
   4 import java.io.File;
   5 import java.io.FileOutputStream;
   6 import java.io.IOException;
   7 import java.io.PrintStream;
   8 import java.util.ArrayList;
   9 import java.util.Collection;
  10 import java.util.Collections;
  11 import java.util.HashMap;
  12 import java.util.HashSet;
  13 import java.util.LinkedList;
  14 import java.util.List;
  15 import java.util.Map;
  16 import java.util.Set;
  17 import java.util.concurrent.Semaphore;
  18 import java.util.function.Consumer;
  19
  20 import org.simantics.databoard.Bindings;
  21 import org.simantics.db.DevelopmentKeys;
  22 import org.simantics.db.debug.ListenerReport;
  23 import org.simantics.db.exception.DatabaseException;
  24 import org.simantics.db.impl.graph.ReadGraphImpl;
  25 import org.simantics.db.impl.graph.WriteGraphImpl;
  26 import org.simantics.db.procedure.ListenerBase;
  27 import org.simantics.utils.Development;
  28 import org.simantics.utils.datastructures.Pair;
  29 import org.simantics.utils.datastructures.collections.CollectionUtils;
  30 import org.slf4j.LoggerFactory;
  31
  32 import gnu.trove.map.hash.THashMap;
  33 import gnu.trove.set.hash.THashSet;
  34
  35 public class QueryListening {
  36
  37     private static final org.slf4j.Logger LOGGER = LoggerFactory.getLogger(QueryListening.class);
  38
  39     private final QueryProcessor                                    processor;
  40     private final Scheduler                                         scheduler;
  41     private final Consumer<Runnable>                                consumer;
  42     private final Map<ListenerBase,ListenerEntry>                   addedEntries = new HashMap<>();
  43
  44     private THashSet<ListenerEntry>                                 scheduledListeners    = new THashSet<ListenerEntry>();
  45     private boolean                                                 firingListeners       = false;
  46
  47     final THashMap<CacheEntry, ArrayList<ListenerEntry>>    listeners = new THashMap<CacheEntry, ArrayList<ListenerEntry>>(10, 0.75f);
  48
  49     private static class ThreadQueue extends ThreadLocal<ArrayList<Runnable>> {
  50
  51         private final Map<Thread,ArrayList<Runnable>> allQueues = new HashMap<>();
  52
  53         private ArrayList<ArrayList<Runnable>> dispatchedQueues = new ArrayList<>();
  54
  55         @Override
  56         protected synchronized ArrayList<Runnable> initialValue() {
  57             ArrayList<Runnable> result = new ArrayList<>();
  58             allQueues.put(Thread.currentThread(), result);
  59             return result;
  60         }
  61
  62         synchronized void sendToExecution() {
  63             ArrayList<Runnable> rs = allQueues.remove(Thread.currentThread());
  64             dispatchedQueues.add(rs);
  65             notify();
  66         }
  67
  68         synchronized ArrayList<ArrayList<Runnable>> getDispatchedQueues() {
  69             ArrayList<ArrayList<Runnable>> result = dispatchedQueues;
  70             dispatchedQueues = new ArrayList<>();
  71             return result;
  72         }
  73
  74     }
  75
  76     private static class Scheduler {
  77
  78         private static final int BUFFER_SIZE = 100;
  79
  80         private final QueryProcessor processor;
  81
  82         private final ThreadQueue queues = new ThreadQueue();
  83
  84         /*
  85          * Access to this field is synchronized using the monitor of 'queues'
  86          * The method flush() shall be called by the single writing thread and the field has been nulled before the
  87          * method can exit. Thus it is not possible for multiple instances of flush Semaphore to exist at the same time.
  88          */
  89         private Semaphore flush = null;
  90
  91         Scheduler(QueryProcessor processor) {
  92             this.processor = processor;
  93         }
  94
  95         private boolean isTerminated() {
  96             return processor.isDisposed();
  97         }
  98
  99         Consumer<Runnable> newConsumer() {
 100             return (task) -> {
 101
 102                 ArrayList<Runnable> l = queues.get();
 103                 l.add(task);
 104                 if(l.size() == BUFFER_SIZE) {
 105                     queues.remove();
 106                     queues.sendToExecution();
 107                 }
 108
 109             };
 110         }
 111
 112         void start() {
 113
 114             Thread thread = new Thread() {
 115
 116                 public void run() {
 117
 118                     synchronized(queues) {
 119                         while(!isTerminated()) {
 120                             try {
 121                                 ArrayList<ArrayList<Runnable>> qs = queues.getDispatchedQueues();
 122                                 for(ArrayList<Runnable> queue : qs) {
 123                                     for(Runnable r : queue)
 124                                         r.run();
 125                                 }
 126                                 if(flush != null) {
 127                                     for(ArrayList<Runnable> queue : queues.allQueues.values()) {
 128                                         for(Runnable r : queue) {
 129                                             r.run();
 130                                         }
 131                                         queue.clear();
 132                                     }
 133                                     Semaphore s = flush;
 134                                     flush = null;
 135                                     s.release();
 136                                 }
 137                                 queues.wait(1000);
 138                             } catch (InterruptedException e) {
 139                                 LOGGER.error("Unexpected interrupt", e);
 140                             }
 141                         }
 142                     }
 143
 144                 };
 145
 146             };
 147
 148             thread.setName("QueryListening");
 149             thread.start();
 150
 151         }
 152
 153         private Semaphore createFlush() {
 154             synchronized(queues) {
 155                 flush = new Semaphore(0);
 156                 queues.notify();
 157                 return flush;
 158             }
 159         }
 160
 161         void flush() {
 162             try {
 163                 createFlush().acquire();
 164             } catch (InterruptedException e) {
 165                 LOGGER.error("Unexpected interrupt", e);
 166             }
 167         }
 168
 169     }
 170
 171     private static class RegisterParentRunnable implements Runnable {
 172
 173         private final CacheEntry parent;
 174         private final CacheEntry child;
 175
 176         public RegisterParentRunnable(CacheEntry parent, CacheEntry child) {
 177             this.parent = parent;
 178             this.child = child;
 179         }
 180
 181         @Override
 182         public void run() {
 183             child.addParent(parent);
 184             if (Development.DEVELOPMENT) {
 185                 if(Development.<Boolean>getProperty(DevelopmentKeys.QUERYPROCESSOR_DEPENDENCIES, Bindings.BOOLEAN)) {
 186                     System.out.println(child + " -> " + parent);
 187                 }
 188             }
 189         }
 190
 191     }
 192
 193     private static class RegisterListenerRunnable implements Runnable {
 194
 195         private final QueryListening queryListening;
 196         private final ListenerBase base;
 197         private final Object procedure;
 198         private final CacheEntry parent;
 199         private final CacheEntry entry;
 200
 201         public RegisterListenerRunnable(QueryListening queryListening, ListenerBase base, Object procedure, CacheEntry parent, CacheEntry entry) {
 202             this.queryListening = queryListening;
 203             this.base = base;
 204             this.procedure = procedure;
 205             this.parent = parent;
 206             this.entry = entry;
 207         }
 208
 209         @Override
 210         public void run() {
 211
 212             assert (entry != null);
 213             assert (procedure != null);
 214
 215             ArrayList<ListenerEntry> list = queryListening.listeners.get(entry);
 216             if (list == null) {
 217                 list = new ArrayList<>(1);
 218                 queryListening.listeners.put(entry, list);
 219             }
 220
 221             ListenerEntry result = new ListenerEntry(entry, base, procedure);
 222             // Equals is here based on base
 223             int currentIndex = list.indexOf(result);
 224             // There was already a listener
 225             if(currentIndex > -1) {
 226                 ListenerEntry current = list.get(currentIndex);
 227                 if(!current.base.isDisposed())
 228                     return;
 229                 list.set(currentIndex, result);
 230             } else {
 231                 list.add(result);
 232             }
 233
 234             if (Development.DEVELOPMENT) {
 235                 if(Development.<Boolean>getProperty(DevelopmentKeys.QUERYPROCESSOR_LISTENERS, Bindings.BOOLEAN)) {
 236                     new Exception().printStackTrace();
 237                     System.err.println("addListener -> " + list.size() + " " + entry + " " + base + " " + procedure);
 238                 }
 239             }
 240
 241             queryListening.addedEntries.put(base, result);
 242
 243         }
 244
 245
 246     }
 247
 248     QueryListening(QueryProcessor processor) {
 249
 250         this.processor = processor;
 251         scheduler = new Scheduler(processor);
 252         consumer = scheduler.newConsumer();
 253         scheduler.start();
 254
 255     }
 256
 257     public boolean hasScheduledUpdates() {
 258         return !scheduledListeners.isEmpty();
 259     }
 260
 261     void sync() {
 262         try {
 263             scheduler.flush();
 264         } catch (Throwable t) {
 265             LOGGER.error("Error while waiting for query dependency management", t);
 266         }
 267     }
 268
 269     void registerDependencies(ReadGraphImpl graph, CacheEntry child, CacheEntry parent, ListenerBase listener, Object procedure, boolean inferred) {
 270
 271         if(inferred) {
 272             assert(listener == null);
 273             return;
 274         }
 275
 276         if(parent != null) {
 277             try {
 278                 if(!child.isImmutable(graph))
 279                     consumer.accept(new RegisterParentRunnable(parent, child));
 280             } catch (DatabaseException e) {
 281                 LOGGER.error("Error while registering query dependencies", e);
 282             }
 283         }
 284
 285         if(listener != null)
 286             if(!listener.isDisposed())
 287                 consumer.accept(new RegisterListenerRunnable(this, listener, procedure, parent, child));
 288
 289     }
 290
 291     void registerFirstKnown(ListenerBase base, Object result) {
 292
 293         if(base == null) return;
 294
 295         consumer.accept(() -> {
 296             ListenerEntry entry = addedEntries.get(base);
 297             if(entry != null) entry.setLastKnown(result);
 298         });
 299
 300     }
 301
 302     void scheduleListener(ListenerEntry entry) {
 303
 304         assert (entry != null);
 305
 306         if (Development.DEVELOPMENT) {
 307             if(Development.<Boolean>getProperty(DevelopmentKeys.QUERYPROCESSOR_LISTENERS, Bindings.BOOLEAN)) {
 308                 System.err.println("Scheduled " + entry.procedure);
 309             }
 310         }
 311
 312         scheduledListeners.add(entry);
 313
 314     }
 315
 316     boolean hasListener(CacheEntry entry) {
 317         if(listeners.get(entry) != null) return true;
 318         return false;
 319     }
 320
 321     boolean hasListenerAfterDisposing(CacheEntry entry) {
 322         if(listeners.get(entry) != null) {
 323             ArrayList<ListenerEntry> entries = listeners.get(entry);
 324             ArrayList<ListenerEntry> list = null;
 325             for (ListenerEntry e : entries) {
 326                 if (e.base.isDisposed()) {
 327                     if(list == null) list = new ArrayList<ListenerEntry>();
 328                     list.add(e);
 329                 }
 330             }
 331             if(list != null) {
 332                 for (ListenerEntry e : list) {
 333                     entries.remove(e);
 334                 }
 335             }
 336             if (entries.isEmpty()) {
 337                 listeners.remove(entry);
 338                 return false;
 339             }
 340             return true;
 341         }
 342         return false;
 343     }
 344
 345     void processListenerReport(CacheEntry<?> entry, Map<CacheEntry, Set<ListenerBase>> workarea) {
 346
 347         if(!workarea.containsKey(entry)) {
 348
 349             HashSet<ListenerBase> ls = new HashSet<ListenerBase>();
 350             for(ListenerEntry e : getListenerEntries(entry))
 351                 ls.add(e.base);
 352
 353             workarea.put(entry, ls);
 354
 355             for(CacheEntry parent : entry.getParents(processor)) {
 356                 processListenerReport(parent, workarea);
 357                 ls.addAll(workarea.get(parent));
 358             }
 359
 360         }
 361
 362     }
 363
 364     public synchronized ListenerReport getListenerReport() throws IOException {
 365
 366         class ListenerReportImpl implements ListenerReport {
 367
 368             Map<CacheEntry, Set<ListenerBase>> workarea = new HashMap<CacheEntry, Set<ListenerBase>>();
 369
 370             @Override
 371             public void print(PrintStream b) {
 372                 Map<ListenerBase, Integer> hist = new HashMap<ListenerBase, Integer>();
 373                 for(Map.Entry<CacheEntry, Set<ListenerBase>> e : workarea.entrySet()) {
 374                     for(ListenerBase l : e.getValue()) {
 375                         Integer i = hist.get(l);
 376                         hist.put(l, i != null ? i-1 : -1);
 377                     }
 378                 }
 379
 380                 for(Pair<ListenerBase, Integer> p : CollectionUtils.valueSortedEntries(hist)) {
 381                     b.print("" + -p.second + " " + p.first + "\n");
 382                 }
 383
 384                 b.flush();
 385             }
 386
 387         }
 388
 389         ListenerReportImpl result = new ListenerReportImpl();
 390
 391         Collection<CacheEntryBase> all = processor.allCaches(new CacheCollectionResult()).toCollection();
 392         for(CacheEntryBase entry : all) {
 393             hasListenerAfterDisposing(entry);
 394         }
 395         for(CacheEntryBase entry : all) {
 396             processListenerReport(entry, result.workarea);
 397         }
 398
 399         return result;
 400
 401     }
 402
 403     public synchronized String reportListeners(File file) throws IOException {
 404
 405         if (!processor.isAlive())
 406             return "Disposed!";
 407
 408         PrintStream b = new PrintStream(new BufferedOutputStream(new FileOutputStream(file)));
 409         ListenerReport report = getListenerReport();
 410         report.print(b);
 411
 412         return "Done reporting listeners.";
 413
 414     }
 415
 416     public void fireListeners(WriteGraphImpl graph) {
 417
 418         assert (!processor.updating);
 419         assert (!processor.cache.collecting);
 420         assert (!firingListeners);
 421
 422         firingListeners = true;
 423
 424         try {
 425
 426             // Performing may cause further events to be scheduled.
 427             while (!scheduledListeners.isEmpty()) {
 428
 429                 // Clone current events to make new entries possible during
 430                 // firing.
 431                 THashSet<ListenerEntry> entries = scheduledListeners;
 432                 scheduledListeners = new THashSet<ListenerEntry>();
 433
 434                 ArrayList<ListenerEntry> schedule = new ArrayList<ListenerEntry>();
 435
 436                 for (ListenerEntry listenerEntry : entries) {
 437
 438                     if (pruneListener(listenerEntry)) {
 439                         if (Development.DEVELOPMENT) {
 440                             if(Development.<Boolean>getProperty(DevelopmentKeys.QUERYPROCESSOR_LISTENERS, Bindings.BOOLEAN)) {
 441                                 new Exception().printStackTrace();
 442                                 System.err.println("Pruned " + listenerEntry.procedure);
 443                             }
 444                         }
 445                         continue;
 446                     }
 447
 448                     final CacheEntry entry = listenerEntry.entry;
 449                     assert (entry != null);
 450
 451                     Object newValue = processor.compareTo(graph, entry, listenerEntry.getLastKnown());
 452
 453                     if (newValue != ListenerEntry.NOT_CHANGED) {
 454                         if (Development.DEVELOPMENT) {
 455                             if(Development.<Boolean>getProperty(DevelopmentKeys.QUERYPROCESSOR_LISTENERS, Bindings.BOOLEAN)) {
 456                                 new Exception().printStackTrace();
 457                                 System.err.println("Add to schedule " + listenerEntry.procedure + " with " + newValue);
 458                             }
 459                         }
 460                         schedule.add(listenerEntry);
 461                         listenerEntry.setLastKnown(entry.getResult());
 462                     }
 463
 464                 }
 465
 466                 for(ListenerEntry listenerEntry : schedule) {
 467                     final CacheEntry entry = listenerEntry.entry;
 468                     if (Development.DEVELOPMENT) {
 469                         if(Development.<Boolean>getProperty(DevelopmentKeys.QUERYPROCESSOR_LISTENERS, Bindings.BOOLEAN)) {
 470                             System.err.println("Firing " + listenerEntry.procedure);
 471                         }
 472                     }
 473                     try {
 474                         if (Development.DEVELOPMENT) {
 475                             if(Development.<Boolean>getProperty(DevelopmentKeys.QUERYPROCESSOR_LISTENERS, Bindings.BOOLEAN)) {
 476                                 System.err.println("Firing " + listenerEntry.procedure + " for " + listenerEntry.entry);
 477                             }
 478                         }
 479                         entry.performFromCache(graph, listenerEntry.procedure);
 480                     } catch (Throwable t) {
 481                         LOGGER.error("Unexpected exception ", t);
 482                     }
 483                 }
 484
 485             }
 486
 487         } finally {
 488             firingListeners = false;
 489         }
 490
 491     }
 492
 493     void updateParents(int indent, CacheEntry entry, LinkedList<UpdateEntry> todo) {
 494
 495         Iterable<CacheEntry> oldParents = entry.getParents(processor);
 496         for (CacheEntry parent : oldParents) {
 497             if(!parent.isDiscarded())
 498                 todo.push(new UpdateEntry(entry, parent, indent + 2));
 499         }
 500
 501     }
 502
 503     private boolean pruneListener(ListenerEntry entry) {
 504
 505         if (entry.base.isDisposed()) {
 506
 507             assert (entry != null);
 508             ArrayList<ListenerEntry> list = listeners.get(entry.entry);
 509             if(list != null) {
 510                 boolean success = list.remove(entry);
 511                 assert (success);
 512                 if (list.isEmpty())
 513                     listeners.remove(entry.entry);
 514             }
 515
 516             return true;
 517
 518         } else {
 519
 520             return false;
 521
 522         }
 523     }
 524
 525     private List<ListenerEntry> getListenerEntries(CacheEntry entry) {
 526         hasListenerAfterDisposing(entry);
 527         if(listeners.get(entry) != null)
 528             return listeners.get(entry);
 529         else
 530             return Collections.emptyList();
 531     }
 532
 533 }