clean up during OSGi bundle shutdown

Change-Id: Ib0b6b203e00a053219bc8076f063dd9f99aa0eba

java/com.sap.sailing.grib/META-INF/MANIFEST.MF

@@ -12,3 +12,6 @@ Require-Bundle: com.sap.sailing.domain.common,
  com.sap.sailing.domain,
  com.sap.sse.common,
  com.sap.sse
+Import-Package: org.osgi.framework
+Bundle-ActivationPolicy: lazy
+Bundle-Activator: com.sap.sailing.grib.impl.Activator

java/com.sap.sailing.grib/src/com/sap/sailing/grib/GribWindFieldFactory.java

@@ -72,5 +72,11 @@ public interface GribWindFieldFactory {
      * Use this method to create formatters for the {@code createGribWindField...} methods that require one.
      */
     Formatter createLogFormatter(Logger logger, Level level);
+    
+    /**
+     * To be called when the bundle shuts down; all resources can be released now, and all persistent file
+     * caches can be cleaned.
+     */
+    void shutdown();
 
 }

java/com.sap.sailing.grib/src/com/sap/sailing/grib/impl/Activator.java

@@ -0,0 +1,21 @@
+package com.sap.sailing.grib.impl;
+
+import org.osgi.framework.BundleActivator;
+import org.osgi.framework.BundleContext;
+
+import com.sap.sailing.grib.GribWindFieldFactory;
+
+public class Activator implements BundleActivator {
+    private GribWindFieldFactory factory;
+    
+    @Override
+    public void start(BundleContext context) throws Exception {
+        factory = GribWindFieldFactoryImpl.INSTANCE;
+    }
+
+    @Override
+    public void stop(BundleContext context) throws Exception {
+        factory.shutdown();
+    }
+
+}

java/com.sap.sailing.grib/src/com/sap/sailing/grib/impl/GribWindFieldFactoryImpl.java

@@ -11,6 +11,7 @@ import java.nio.file.Path;
 import java.util.ArrayList;
 import java.util.Formatter;
 import java.util.HashMap;
+import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
 import java.util.Map.Entry;
@@ -53,15 +54,7 @@ public class GribWindFieldFactoryImpl implements GribWindFieldFactory {
                     while (!finished) {
                         try {
                             final Reference<? extends GribWindField> ref = referenceQueue.remove();
-                            final File dir;
-                            synchronized (GribWindFieldFactoryImpl.this) {
-                                dir = filesToCleanWhenGribWindFieldNoLongerUsed.remove(ref);
-                                finished = filesToCleanWhenGribWindFieldNoLongerUsed.isEmpty();
-                                if (finished) {
-                                    fileSystemCleaner = null;
-                                }
-                            }
-                            rm_rf(dir);
+                            finished = cleanup(ref);
                         } catch (InterruptedException e) {
                             logger.log(Level.WARNING, "Interrupted while waiting for weak reference, giving up", e);
                             finished = true;
@@ -73,7 +66,30 @@ public class GribWindFieldFactoryImpl implements GribWindFieldFactory {
             }
         }
     }
+
+    private boolean cleanup(final Reference<? extends GribWindField> ref) {
+        boolean finished;
+        final File dir;
+        synchronized (GribWindFieldFactoryImpl.this) {
+            dir = filesToCleanWhenGribWindFieldNoLongerUsed.remove(ref);
+            finished = filesToCleanWhenGribWindFieldNoLongerUsed.isEmpty();
+            if (finished) {
+                fileSystemCleaner = null;
+            }
+        }
+        rm_rf(dir);
+        return finished;
+    }
     
+    @Override
+    public synchronized void shutdown() {
+        for (Iterator<WeakReference<GribWindField>> i=filesToCleanWhenGribWindFieldNoLongerUsed.keySet().iterator(); i.hasNext(); ) {
+            final WeakReference<GribWindField> ref = i.next();
+            cleanup(ref);
+            i.remove();
+        }
+    }
+
     /**
      * Removes directory and all its contents
      */
@@ -86,6 +102,7 @@ public class GribWindFieldFactoryImpl implements GribWindFieldFactory {
                 f.delete();
             }
         }
+        dir.delete();
     }
 
     @Override