Fix file update monitor shutdown (#6835)

src/main/java/org/jabref/Globals.java

@@ -131,6 +131,7 @@ public static FileUpdateMonitor getFileUpdateMonitor() {
 
     public static void shutdownThreadPools() {
         TASK_EXECUTOR.shutdown();
+        fileUpdateMonitor.shutdown();
         JabRefExecutorService.INSTANCE.shutdownEverything();
     }
 

src/main/java/org/jabref/gui/collab/DatabaseChangeMonitor.java

@@ -20,7 +20,7 @@ public class DatabaseChangeMonitor implements FileUpdateListener {
     private final BibDatabaseContext database;
     private final FileUpdateMonitor fileMonitor;
     private final List<DatabaseChangeListener> listeners;
-    private TaskExecutor taskExecutor;
+    private final TaskExecutor taskExecutor;
 
     public DatabaseChangeMonitor(BibDatabaseContext database, FileUpdateMonitor fileMonitor, TaskExecutor taskExecutor) {
         this.database = database;

src/main/java/org/jabref/gui/util/DefaultFileUpdateMonitor.java

@@ -1,13 +1,15 @@
 package org.jabref.gui.util;
 
 import java.io.IOException;
+import java.nio.file.ClosedWatchServiceException;
 import java.nio.file.FileSystems;
 import java.nio.file.Path;
 import java.nio.file.StandardWatchEventKinds;
 import java.nio.file.WatchEvent;
 import java.nio.file.WatchKey;
 import java.nio.file.WatchService;
 import java.util.Optional;
+import java.util.concurrent.atomic.AtomicBoolean;
 
 import org.jabref.JabRefException;
 import org.jabref.model.util.FileUpdateListener;
@@ -31,6 +33,7 @@ public class DefaultFileUpdateMonitor implements Runnable, FileUpdateMonitor {
 
     private final Multimap<Path, FileUpdateListener> listeners = ArrayListMultimap.create(20, 4);
     private WatchService watcher;
+    private final AtomicBoolean notShutdown = new AtomicBoolean(true);
     private Optional<JabRefException> filesystemMonitorFailure;
 
     @Override
@@ -39,11 +42,11 @@ public void run() {
             this.watcher = watcher;
             filesystemMonitorFailure = Optional.empty();
 
-            while (true) {
+            while (notShutdown.get()) {
                 WatchKey key;
                 try {
                     key = watcher.take();
-                } catch (InterruptedException e) {
+                } catch (InterruptedException | ClosedWatchServiceException e) {
                     return;
                 }
 
@@ -66,11 +69,12 @@ public void run() {
             }
         } catch (IOException e) {
             filesystemMonitorFailure = Optional.of(new WatchServiceUnavailableException(e.getMessage(),
-                    e.getLocalizedMessage(), e.getCause()));
+                                                                                        e.getLocalizedMessage(), e.getCause()));
             LOGGER.warn(filesystemMonitorFailure.get().getLocalizedMessage(), e);
         }
     }
 
+    @Override
     public boolean isActive() {
         return filesystemMonitorFailure.isEmpty();
     }
@@ -93,4 +97,15 @@ public void addListenerForFile(Path file, FileUpdateListener listener) throws IO
     public void removeListener(Path path, FileUpdateListener listener) {
         listeners.remove(path, listener);
     }
+
+    @Override
+    public void shutdown() {
+        try {
+            notShutdown.set(false);
+            watcher.close();
+        } catch (IOException e) {
+            LOGGER.error("error closing watcher", e);
+        }
+
+    }
 }

src/main/java/org/jabref/logic/util/DelayTaskThrottler.java

@@ -1,7 +1,8 @@
 package org.jabref.logic.util;
 
-import java.util.concurrent.Future;
+import java.util.concurrent.Callable;
 import java.util.concurrent.RejectedExecutionException;
+import java.util.concurrent.ScheduledFuture;
 import java.util.concurrent.ScheduledThreadPoolExecutor;
 import java.util.concurrent.TimeUnit;
 
@@ -14,6 +15,7 @@
  * This class allows to throttle a list of tasks.
  * Use case: you have an event that occurs often, and every time you want to invoke the same task.
  * However, if a lot of events happen in a relatively short time span, then only one task should be invoked.
+ * @param <T>
  *
  * @implNote Once {@link #schedule(Runnable)} is called, the task is delayed for a given time span.
  *         If during this time, {@link #schedule(Runnable)} is called again, then the original task is canceled and the new one scheduled.
@@ -25,7 +27,7 @@ public class DelayTaskThrottler {
     private final ScheduledThreadPoolExecutor executor;
     private final int delay;
 
-    private Future<?> scheduledTask;
+    private ScheduledFuture<?> scheduledTask;
 
     /**
      * @param delay delay in milliseconds
@@ -37,7 +39,7 @@ public DelayTaskThrottler(int delay) {
         this.executor.setExecuteExistingDelayedTasksAfterShutdownPolicy(false);
     }
 
-    public void schedule(Runnable command) {
+    public ScheduledFuture<?> schedule(Runnable command) {
         if (scheduledTask != null) {
             scheduledTask.cancel(false);
         }
@@ -46,6 +48,19 @@ public void schedule(Runnable command) {
         } catch (RejectedExecutionException e) {
             LOGGER.debug("Rejecting while another process is already running.");
         }
+        return scheduledTask;
+    }
+
+    public <T> ScheduledFuture<?> scheduleTask(Callable<?> command) {
+        if (scheduledTask != null) {
+            scheduledTask.cancel(false);
+        }
+        try {
+            scheduledTask = executor.schedule(command, delay, TimeUnit.MILLISECONDS);
+        } catch (RejectedExecutionException e) {
+            LOGGER.debug("Rejecting while another process is already running.");
+        }
+        return scheduledTask;
     }
 
     /**

src/main/java/org/jabref/model/database/event/CoarseChangeFilter.java

@@ -34,7 +34,7 @@ public CoarseChangeFilter(BibDatabaseContext bibDatabaseContext) {
     }
 
     @Subscribe
-    public synchronized void listen(@SuppressWarnings("unused") BibDatabaseContextChangedEvent event) {
+    public synchronized void listen(BibDatabaseContextChangedEvent event) {
         Runnable eventPost = () -> {
             // Reset total change delta
             totalDelta = 0;
@@ -53,7 +53,7 @@ public synchronized void listen(@SuppressWarnings("unused") BibDatabaseContextCh
             // If editing is started
             boolean isNewEdit = lastFieldChanged.isEmpty();
             // If other field is edited
-            boolean isEditOnOtherField = !lastFieldChanged.get().equals(fieldChange.getField());
+            boolean isEditOnOtherField = !isNewEdit && !lastFieldChanged.get().equals(fieldChange.getField());
             // Only deltas of 1 registered by fieldChange, major change means editing much content
             boolean isMajorChange = totalDelta >= 100;
 

src/main/java/org/jabref/model/util/DummyFileUpdateMonitor.java

@@ -7,18 +7,24 @@
  * Normally, you want to use {@link org.jabref.gui.util.DefaultFileUpdateMonitor} except if you don't care about updates.
  */
 public class DummyFileUpdateMonitor implements FileUpdateMonitor {
+
     @Override
     public void addListenerForFile(Path file, FileUpdateListener listener) {
-
+        // empty
     }
 
     @Override
     public void removeListener(Path path, FileUpdateListener listener) {
-
+        // empty
     }
 
     @Override
     public boolean isActive() {
         return false;
     }
+
+    @Override
+    public void shutdown() {
+        // empty
+    }
 }

src/main/java/org/jabref/model/util/FileUpdateMonitor.java

@@ -24,4 +24,9 @@ public interface FileUpdateMonitor {
      * @return true is process is running; false otherwise.
      */
     boolean isActive();
+
+    /**
+     *  stops watching for changes
+     */
+    void shutdown();
 }