A session of compile warning hunt

bundles/org.openhab.core/src/main/java/org/openhab/core/cache/ExpiringCache.java

@@ -67,6 +67,7 @@ public ExpiringCache(long expiry, Supplier<@Nullable V> action) {
      * Returns the value - possibly from the cache, if it is still valid.
      */
     public synchronized @Nullable V getValue() {
+        @Nullable
         V cachedValue = value.get();
         if (cachedValue == null || isExpired()) {
             return refreshValue();
@@ -98,6 +99,7 @@ public final synchronized void invalidateValue() {
      * @return the new value
      */
     public synchronized @Nullable V refreshValue() {
+        @Nullable
         V freshValue = action.get();
         value = new SoftReference<>(freshValue);
         expiresAt = calcExpiresAt();

bundles/org.openhab.core/src/main/java/org/openhab/core/cache/lru/LRUMediaCache.java

@@ -132,13 +132,11 @@ private void cleanCacheDirectory() throws IOException {
             // 2 clean orphan (part of a pair (file + metadata) without a corresponding partner)
             // 2-a delete a file without its metadata
             for (Path path : filesInCacheFolder) {
-                if (path != null) {
-                    String fileName = path.getFileName().toString();
-                    // check corresponding metadata in storage
-                    V metadata = storage.get(fileName);
-                    if (metadata == null) {
-                        Files.delete(path);
-                    }
+                String fileName = path.getFileName().toString();
+                // check corresponding metadata in storage
+                V metadata = storage.get(fileName);
+                if (metadata == null) {
+                    Files.delete(path);
                 }
             }
             // 2-b delete metadata without corresponding file

bundles/org.openhab.core/src/main/java/org/openhab/core/common/PoolBasedSequentialScheduledExecutorService.java

@@ -22,7 +22,6 @@
 import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.ExecutionException;
 import java.util.concurrent.Executor;
-import java.util.concurrent.Executors;
 import java.util.concurrent.Future;
 import java.util.concurrent.RejectedExecutionException;
 import java.util.concurrent.RunnableFuture;
@@ -43,7 +42,7 @@
 
 /**
  * A ScheduledExecutorService that will sequentially perform the tasks like a
- * {@link Executors#newSingleThreadScheduledExecutor} backed by a thread pool.
+ * {@link java.util.concurrent.Executors#newSingleThreadScheduledExecutor} backed by a thread pool.
  * This is a drop in replacement to a ScheduledExecutorService with one thread to avoid a lot of threads created, idling
  * most of the time and wasting memory on low-end devices.
  *

bundles/org.openhab.core/src/main/java/org/openhab/core/common/ThreadFactoryBuilder.java

@@ -15,8 +15,6 @@
 import static java.util.concurrent.Executors.defaultThreadFactory;
 
 import java.lang.Thread.UncaughtExceptionHandler;
-import java.util.concurrent.Executor;
-import java.util.concurrent.Executors;
 import java.util.concurrent.ThreadFactory;
 import java.util.concurrent.atomic.AtomicInteger;
 
@@ -25,10 +23,12 @@
 
 /**
  * A builder for {@link ThreadFactory} instances. This builder is intended to be used for creating thread factories to
- * be used, e.g., when creating {@link Executor}s via the {@link Executors} utility methods.
+ * be used, e.g., when creating {@link java.util.concurrent.Executor}s via the {@link java.util.concurrent.Executors}
+ * utility methods.
  * <p>
  * The built {@link ThreadFactory} uses a wrapped {@link ThreadFactory} to create threads (defaulting to
- * {@link Executors#defaultThreadFactory()}, and then overwrites thread properties as indicated in the build process.
+ * {@link java.util.concurrent.Executors#defaultThreadFactory()}, and then overwrites thread properties as indicated in
+ * the build process.
  *
  * @author Henning Sudbrock - Initial contribution
  */
@@ -60,7 +60,7 @@ private ThreadFactoryBuilder() {
     /**
      * Sets the wrapped thread factory used to create threads.
      * <p>
-     * If set to null, {@link Executors#defaultThreadFactory()} is used.
+     * If set to null, {@link java.util.concurrent.Executors#defaultThreadFactory()} is used.
      * <p>
      * Defaults to null.
      *

bundles/org.openhab.core/src/main/java/org/openhab/core/common/registry/AbstractRegistry.java

@@ -442,9 +442,9 @@ protected void addProvider(Provider<E> provider) {
         }
         elementsAdded.forEach(this::notifyListenersAboutAddedElement);
 
-        if (provider instanceof ManagedProvider && providerClazz != null && readyService != null) {
-            readyService.markReady(
-                    new ReadyMarker("managed", providerClazz.getSimpleName().replace("Provider", "").toLowerCase()));
+        if (provider instanceof ManagedProvider && providerClazz instanceof Class clazz
+                && readyService instanceof ReadyService rs) {
+            rs.markReady(new ReadyMarker("managed", clazz.getSimpleName().replace("Provider", "").toLowerCase()));
         }
         logger.debug("Provider \"{}\" has been added.", provider.getClass().getName());
     }
@@ -688,9 +688,9 @@ protected void unsetReadyService(ReadyService readyService) {
      * @param event the event
      */
     protected void postEvent(Event event) {
-        if (eventPublisher != null) {
+        if (eventPublisher instanceof EventPublisher ep) {
             try {
-                eventPublisher.post(event);
+                ep.post(event);
             } catch (RuntimeException ex) {
                 logger.error("Cannot post event of type \"{}\".", event.getType(), ex);
             }

bundles/org.openhab.core/src/main/java/org/openhab/core/events/AbstractEvent.java

@@ -61,9 +61,9 @@ public String getPayload() {
     public int hashCode() {
         final int prime = 31;
         int result = 1;
-        result = prime * result + ((payload == null) ? 0 : payload.hashCode());
-        result = prime * result + ((source == null) ? 0 : source.hashCode());
-        result = prime * result + ((topic == null) ? 0 : topic.hashCode());
+        result = prime * result + payload.hashCode();
+        result = prime * result + (source instanceof String local ? local.hashCode() : 0);
+        result = prime * result + topic.hashCode();
         return result;
     }
 
@@ -79,11 +79,7 @@ public boolean equals(@Nullable Object obj) {
             return false;
         }
         AbstractEvent other = (AbstractEvent) obj;
-        if (payload == null) {
-            if (other.payload != null) {
-                return false;
-            }
-        } else if (!payload.equals(other.payload)) {
+        if (!payload.equals(other.payload)) {
             return false;
         }
         if (source == null) {
@@ -93,11 +89,7 @@ public boolean equals(@Nullable Object obj) {
         } else if (!source.equals(other.source)) {
             return false;
         }
-        if (topic == null) {
-            if (other.topic != null) {
-                return false;
-            }
-        } else if (!topic.equals(other.topic)) {
+        if (!topic.equals(other.topic)) {
             return false;
         }
         return true;

bundles/org.openhab.core/src/main/java/org/openhab/core/events/system/SystemEventFactory.java

@@ -19,7 +19,6 @@
 import org.openhab.core.events.AbstractEventFactory;
 import org.openhab.core.events.Event;
 import org.openhab.core.events.EventFactory;
-import org.openhab.core.types.Type;
 import org.osgi.service.component.annotations.Component;
 
 /**
@@ -38,7 +37,7 @@ public SystemEventFactory() {
     }
 
     /**
-     * Creates a trigger event from a {@link Type}.
+     * Creates a trigger event from a {@link org.openhab.core.types.Type}.
      *
      * @param startlevel Startlevel of system
      * @return Created start level event.

bundles/org.openhab.core/src/main/java/org/openhab/core/i18n/LocalizedKey.java

@@ -46,7 +46,7 @@ public int hashCode() {
         final int prime = 31;
         int result = 1;
         result = prime * result + key.hashCode();
-        result = prime * result + ((locale != null) ? locale.hashCode() : 0);
+        result = prime * result + (locale instanceof String string ? string.hashCode() : 0);
         return result;
     }
 

bundles/org.openhab.core/src/main/java/org/openhab/core/internal/auth/AuthenticationManagerImpl.java

@@ -48,9 +48,7 @@ public Authentication authenticate(Credentials credentials) throws Authenticatio
                 unmatched = false;
                 try {
                     Authentication authentication = provider.authenticate(credentials);
-                    if (authentication != null) {
-                        return authentication;
-                    }
+                    return authentication;
                 } catch (AuthenticationException e) {
                     logger.info("Failed to authenticate credentials {} with provider {}", credentials.getClass(),
                             provider, e);

bundles/org.openhab.core/src/main/java/org/openhab/core/internal/auth/ManagedUserProvider.java

@@ -13,17 +13,15 @@
 package org.openhab.core.internal.auth;
 
 import org.eclipse.jdt.annotation.NonNullByDefault;
-import org.openhab.core.auth.ManagedUser;
 import org.openhab.core.auth.User;
 import org.openhab.core.common.registry.DefaultAbstractManagedProvider;
-import org.openhab.core.common.registry.ManagedProvider;
 import org.openhab.core.storage.StorageService;
 import org.osgi.service.component.annotations.Activate;
 import org.osgi.service.component.annotations.Component;
 import org.osgi.service.component.annotations.Reference;
 
 /**
- * A {@link ManagedProvider} for {@link ManagedUser} entities
+ * A {@link org.openhab.core.common.registry.ManagedProvider} for {@link org.openhab.core.auth.ManagedUser} entities
  *
  * @author Yannick Schaus - initial contribution
  */

bundles/org.openhab.core/src/main/java/org/openhab/core/internal/common/AbstractInvocationHandler.java

@@ -117,8 +117,8 @@ void handleTimeout(Method method, Invocation invocation) {
         } else {
             logger.debug(MSG_TIMEOUT_Q, timeout, toString(invocation.getInvocationStack()));
         }
-        if (timeoutHandler != null) {
-            timeoutHandler.run();
+        if (timeoutHandler instanceof Runnable handler) {
+            handler.run();
         }
     }
 

bundles/org.openhab.core/src/main/java/org/openhab/core/internal/events/OSGiEventManager.java

@@ -17,7 +17,6 @@
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.CopyOnWriteArraySet;
 
-import org.openhab.core.events.Event;
 import org.openhab.core.events.EventFactory;
 import org.openhab.core.events.EventSubscriber;
 import org.osgi.service.component.ComponentContext;
@@ -33,8 +32,8 @@
  * The {@link OSGiEventManager} provides an OSGi based default implementation of the openHAB event bus.
  *
  * The OSGiEventHandler tracks {@link EventSubscriber}s and {@link EventFactory}s, receives OSGi events (by
- * implementing the OSGi {@link EventHandler} interface) and dispatches the received OSGi events as OH {@link Event}s
- * to the {@link EventSubscriber}s if the provided filter applies.
+ * implementing the OSGi {@link EventHandler} interface) and dispatches the received OSGi events
+ * as OH {@link org.openhab.core.events.Event}s to the {@link EventSubscriber}s if the provided filter applies.
  *
  * @author Stefan Bußweiler - Initial contribution
  * @author Markus Rathgeb - Return on received events as fast as possible (handle event in another thread)

bundles/org.openhab.core/src/main/java/org/openhab/core/internal/i18n/I18nProviderImpl.java

@@ -22,7 +22,6 @@
 import java.util.Locale;
 import java.util.Map;
 import java.util.Objects;
-import java.util.ResourceBundle;
 import java.util.Set;
 
 import javax.measure.Quantity;
@@ -100,7 +99,8 @@
  * and {@link LocationProvider} service interfaces.
  *
  * <p>
- * This implementation uses the i18n mechanism of Java ({@link ResourceBundle}) to translate a given key into text. The
+ * This implementation uses the i18n mechanism of Java ({@link java.util.ResourceBundle}) to translate a
+ * given key into text. The
  * resources must be placed under the specific directory {@link LanguageResourceBundleManager#RESOURCE_DIRECTORY} within
  * the certain modules. Each module is tracked in the platform by using the {@link ResourceBundleTracker} and managed by
  * using one certain {@link LanguageResourceBundleManager} which is responsible for the translation.
@@ -134,7 +134,6 @@ public class I18nProviderImpl
     public static final String REGION = "region";
     public static final String VARIANT = "variant";
     private @Nullable Locale locale;
-    private @Nullable String currencyCode;
 
     // TranslationProvider
     private final ResourceBundleTracker resourceBundleTracker;
@@ -301,7 +300,7 @@ private void setTimeZone(final @Nullable String zoneId) {
 
         if (oldTimeZone != null && this.timeZone == null) {
             logger.info("Time zone is not set, falling back to the default time zone.");
-        } else if (this.timeZone != null && !this.timeZone.equals(oldTimeZone)) {
+        } else if (this.timeZone instanceof ZoneId zId && !zId.equals(oldTimeZone)) {
             logger.info("Time zone set to '{}'.", this.timeZone);
         }
     }

bundles/org.openhab.core/src/main/java/org/openhab/core/internal/i18n/LanguageResourceBundleManager.java

@@ -183,9 +183,7 @@ private String getTranslatedText(String resourceName, String key, Locale locale)
             ResourceBundle resourceBundle = ResourceBundle.getBundle(resourceName, locale, this.resourceClassLoader,
                     Control.getNoFallbackControl(Control.FORMAT_PROPERTIES));
 
-            if (resourceBundle != null) {
-                return resourceBundle.getString(key);
-            }
+            return resourceBundle.getString(key);
         } catch (Exception ex) {
             // nothing to do
         }

bundles/org.openhab.core/src/main/java/org/openhab/core/internal/items/ItemBuilderFactoryImpl.java

@@ -20,16 +20,15 @@
 import org.openhab.core.items.ItemBuilder;
 import org.openhab.core.items.ItemBuilderFactory;
 import org.openhab.core.items.ItemFactory;
-import org.openhab.core.library.CoreItemFactory;
 import org.osgi.service.component.annotations.Activate;
 import org.osgi.service.component.annotations.Component;
 import org.osgi.service.component.annotations.Reference;
 import org.osgi.service.component.annotations.ReferenceCardinality;
 import org.osgi.service.component.annotations.ReferencePolicy;
 
 /**
- * Provides an {@link ItemBuilder} with all available {@link ItemFactory}s set. The {@link CoreItemFactory} will always
- * be present.
+ * Provides an {@link ItemBuilder} with all available {@link ItemFactory}s set.
+ * The {@link org.openhab.core.library.CoreItemFactory} will always be present.
  *
  * @author Henning Treu - Initial contribution
  */

bundles/org.openhab.core/src/main/java/org/openhab/core/internal/items/ItemRegistryImpl.java

@@ -156,28 +156,24 @@ public Collection<Item> getItems(String pattern) {
 
     private void addToGroupItems(Item item, List<String> groupItemNames) {
         for (String groupName : groupItemNames) {
-            if (groupName != null) {
-                try {
-                    if (getItem(groupName) instanceof GroupItem groupItem) {
-                        groupItem.addMember(item);
-                    }
-                } catch (ItemNotFoundException e) {
-                    // the group might not yet be registered, let's ignore this
+            try {
+                if (getItem(groupName) instanceof GroupItem groupItem) {
+                    groupItem.addMember(item);
                 }
+            } catch (ItemNotFoundException e) {
+                // the group might not yet be registered, let's ignore this
             }
         }
     }
 
     private void replaceInGroupItems(Item oldItem, Item newItem, List<String> groupItemNames) {
         for (String groupName : groupItemNames) {
-            if (groupName != null) {
-                try {
-                    if (getItem(groupName) instanceof GroupItem groupItem) {
-                        groupItem.replaceMember(oldItem, newItem);
-                    }
-                } catch (ItemNotFoundException e) {
-                    // the group might not yet be registered, let's ignore this
+            try {
+                if (getItem(groupName) instanceof GroupItem groupItem) {
+                    groupItem.replaceMember(oldItem, newItem);
                 }
+            } catch (ItemNotFoundException e) {
+                // the group might not yet be registered, let's ignore this
             }
         }
     }
@@ -229,14 +225,12 @@ private void addMembersToGroupItem(GroupItem groupItem) {
 
     private void removeFromGroupItems(Item item, List<String> groupItemNames) {
         for (String groupName : groupItemNames) {
-            if (groupName != null) {
-                try {
-                    if (getItem(groupName) instanceof GroupItem groupItem) {
-                        groupItem.removeMember(item);
-                    }
-                } catch (ItemNotFoundException e) {
-                    // the group might not yet be registered, let's ignore this
+            try {
+                if (getItem(groupName) instanceof GroupItem groupItem) {
+                    groupItem.removeMember(item);
                 }
+            } catch (ItemNotFoundException e) {
+                // the group might not yet be registered, let's ignore this
             }
         }
     }