Added nullness annotations to Item events (#2384)

* Added nullness annotations to Item events
* Added nullness annotations to tests

Signed-off-by: Christoph Weitkamp <github@christophweitkamp.de>

bundles/org.openhab.core.automation.module.script/src/main/java/org/openhab/core/automation/module/script/internal/defaultscope/ScriptBusEvent.java

@@ -91,7 +91,11 @@ public class ScriptBusEvent {
             try {
                 Item item = itemRegistry.getItem(itemName);
                 Command command = TypeParser.parseCommand(item.getAcceptedCommandTypes(), commandString);
-                eventPublisher.post(ItemEventFactory.createCommandEvent(itemName, command));
+                if (command != null) {
+                    eventPublisher.post(ItemEventFactory.createCommandEvent(itemName, command));
+                } else {
+                    LoggerFactory.getLogger(ScriptBusEvent.class).warn("Command '{}' cannot be parsed.", commandString);
+                }
             } catch (ItemNotFoundException e) {
                 LoggerFactory.getLogger(ScriptBusEvent.class).warn("Item '{}' does not exist.", itemName);
             }
@@ -151,7 +155,11 @@ public class ScriptBusEvent {
             try {
                 Item item = itemRegistry.getItem(itemName);
                 State state = TypeParser.parseState(item.getAcceptedDataTypes(), stateString);
-                eventPublisher.post(ItemEventFactory.createStateEvent(itemName, state));
+                if (state != null) {
+                    eventPublisher.post(ItemEventFactory.createStateEvent(itemName, state));
+                } else {
+                    LoggerFactory.getLogger(ScriptBusEvent.class).warn("State '{}' cannot be parsed.", stateString);
+                }
             } catch (ItemNotFoundException e) {
                 LoggerFactory.getLogger(ScriptBusEvent.class).warn("Item '{}' does not exist.", itemName);
             }

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

@@ -12,17 +12,20 @@
  */
 package org.openhab.core.events;
 
+import org.eclipse.jdt.annotation.NonNullByDefault;
+
 /**
  * The {@link EventPublisher} posts {@link Event}s through the openHAB event bus in an asynchronous way.
  * Posted events can be received by implementing the {@link EventSubscriber} callback interface.
  *
  * @author Stefan Bußweiler - Initial contribution
  */
+@NonNullByDefault
 public interface EventPublisher {
 
     /**
      * Posts an event through the event bus in an asynchronous way.
-     * 
+     *
      * @param event the event posted through the event bus
      * @throws IllegalArgumentException if the event is null
      * @throws IllegalArgumentException if one of the event properties type, payload or topic is null

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

@@ -12,19 +12,22 @@
  */
 package org.openhab.core.events;
 
+import org.eclipse.jdt.annotation.NonNullByDefault;
+
 /**
  * The {@link TopicEventFilter} is a default openHAB {@link EventFilter} implementation that ensures filtering
  * of events based on an event topic.
- * 
+ *
  * @author Stefan Bußweiler - Initial contribution
  */
+@NonNullByDefault
 public class TopicEventFilter implements EventFilter {
 
     private final String topicRegex;
 
     /**
      * Constructs a new topic event filter.
-     * 
+     *
      * @param topicRegex the regular expression of a topic
      * @see <a href="http://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html">Java Regex</a>
      */

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

@@ -20,6 +20,7 @@ import java.util.Hashtable;
 
 import org.openhab.core.events.Event;
 import org.openhab.core.events.EventPublisher;
+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.event.EventAdmin;
@@ -36,17 +37,13 @@ import org.osgi.service.event.EventAdmin;
 @Component
 public class OSGiEventPublisher implements EventPublisher {
 
-    private EventAdmin osgiEventAdmin;
+    private final EventAdmin osgiEventAdmin;
 
-    @Reference
+    @Activate
-    protected void setEventAdmin(EventAdmin eventAdmin) {
+    public OSGiEventPublisher(final @Reference EventAdmin eventAdmin) {
         this.osgiEventAdmin = eventAdmin;
     }
 
-    protected void unsetEventAdmin(EventAdmin eventAdmin) {
-        this.osgiEventAdmin = null;
-    }
-
     @Override
     public void post(final Event event) throws IllegalArgumentException, IllegalStateException {
         EventAdmin eventAdmin = this.osgiEventAdmin;
@@ -64,8 +61,9 @@ public class OSGiEventPublisher implements EventPublisher {
                     properties.put("type", event.getType());
                     properties.put("payload", event.getPayload());
                     properties.put("topic", event.getTopic());
-                    if (event.getSource() != null) {
+                    String source = event.getSource();
-                        properties.put("source", event.getSource());
+                    if (source != null) {
+                        properties.put("source", source);
                     }
                     eventAdmin.postEvent(new org.osgi.service.event.Event("openhab", properties));
                     return null;

bundles/org.openhab.core/src/main/java/org/openhab/core/items/events/AbstractItemEventSubscriber.java

@@ -14,6 +14,8 @@ package org.openhab.core.items.events;
 
 import java.util.Set;
 
+import org.eclipse.jdt.annotation.NonNullByDefault;
+import org.eclipse.jdt.annotation.Nullable;
 import org.openhab.core.events.Event;
 import org.openhab.core.events.EventFilter;
 import org.openhab.core.events.EventSubscriber;
@@ -28,6 +30,7 @@ import org.openhab.core.events.EventSubscriber;
  *
  * @author Stefan Bußweiler - Initial contribution
  */
+@NonNullByDefault
 public abstract class AbstractItemEventSubscriber implements EventSubscriber {
 
     private final Set<String> subscribedEventTypes = Set.of(ItemStateEvent.TYPE, ItemCommandEvent.TYPE);
@@ -38,7 +41,7 @@ public abstract class AbstractItemEventSubscriber implements EventSubscriber {
     }
 
     @Override
-    public EventFilter getEventFilter() {
+    public @Nullable EventFilter getEventFilter() {
         return null;
     }
 

bundles/org.openhab.core/src/main/java/org/openhab/core/items/events/AbstractItemRegistryEvent.java

@@ -12,6 +12,8 @@
  */
 package org.openhab.core.items.events;
 
+import org.eclipse.jdt.annotation.NonNullByDefault;
+import org.eclipse.jdt.annotation.Nullable;
 import org.openhab.core.events.AbstractEvent;
 import org.openhab.core.items.ItemRegistry;
 import org.openhab.core.items.dto.ItemDTO;
@@ -22,6 +24,7 @@ import org.openhab.core.items.dto.ItemDTO;
  *
  * @author Stefan Bußweiler - Initial contribution
  */
+@NonNullByDefault
 public abstract class AbstractItemRegistryEvent extends AbstractEvent {
 
     private final ItemDTO item;
@@ -31,17 +34,17 @@ public abstract class AbstractItemRegistryEvent extends AbstractEvent {
      *
      * @param topic the topic
      * @param payload the payload
-     * @param source the source, can be null
+     * @param source the source
      * @param item the item data transfer object
      */
-    protected AbstractItemRegistryEvent(String topic, String payload, String source, ItemDTO item) {
+    protected AbstractItemRegistryEvent(String topic, String payload, @Nullable String source, ItemDTO item) {
         super(topic, payload, source);
         this.item = item;
     }
 
     /**
      * Gets the item.
-     * 
+     *
      * @return the item
      */
     public ItemDTO getItem() {

bundles/org.openhab.core/src/main/java/org/openhab/core/items/events/ItemAddedEvent.java

@@ -12,6 +12,7 @@
  */
 package org.openhab.core.items.events;
 
+import org.eclipse.jdt.annotation.NonNullByDefault;
 import org.openhab.core.items.dto.ItemDTO;
 
 /**
@@ -20,6 +21,7 @@ import org.openhab.core.items.dto.ItemDTO;
  *
  * @author Stefan Bußweiler - Initial contribution
  */
+@NonNullByDefault
 public class ItemAddedEvent extends AbstractItemRegistryEvent {
 
     /**

bundles/org.openhab.core/src/main/java/org/openhab/core/items/events/ItemEventFactory.java

@@ -16,9 +16,10 @@ import java.lang.reflect.InvocationTargetException;
 import java.lang.reflect.Method;
 import java.util.LinkedList;
 import java.util.List;
-import java.util.stream.Collectors;
+import java.util.Set;
-import java.util.stream.Stream;
 
+import org.eclipse.jdt.annotation.NonNullByDefault;
+import org.eclipse.jdt.annotation.Nullable;
 import org.openhab.core.events.AbstractEventFactory;
 import org.openhab.core.events.Event;
 import org.openhab.core.events.EventFactory;
@@ -39,8 +40,8 @@ import org.osgi.service.component.annotations.Component;
  * @author Stefan Bußweiler - Initial contribution
  */
 @Component(immediate = true, service = EventFactory.class)
+@NonNullByDefault
 public class ItemEventFactory extends AbstractEventFactory {
-
     private static final String TYPE_POSTFIX = "Type";
 
     private static final String CORE_LIBRARY_PACKAGE = "org.openhab.core.library.types.";
@@ -65,13 +66,14 @@ public class ItemEventFactory extends AbstractEventFactory {
      * Constructs a new ItemEventFactory.
      */
     public ItemEventFactory() {
-        super(Stream.of(ItemCommandEvent.TYPE, ItemStateEvent.TYPE, ItemStatePredictedEvent.TYPE,
+        super(Set.of(ItemCommandEvent.TYPE, ItemStateEvent.TYPE, ItemStatePredictedEvent.TYPE,
                 ItemStateChangedEvent.TYPE, ItemAddedEvent.TYPE, ItemUpdatedEvent.TYPE, ItemRemovedEvent.TYPE,
-                GroupItemStateChangedEvent.TYPE).collect(Collectors.toSet()));
+                GroupItemStateChangedEvent.TYPE));
     }
 
     @Override
-    protected Event createEventByType(String eventType, String topic, String payload, String source) throws Exception {
+    protected Event createEventByType(String eventType, String topic, String payload, @Nullable String source)
+            throws Exception {
         if (ItemCommandEvent.TYPE.equals(eventType)) {
             return createCommandEvent(topic, payload, source);
         } else if (ItemStateEvent.TYPE.equals(eventType)) {
@@ -101,14 +103,14 @@ public class ItemEventFactory extends AbstractEventFactory {
         return new GroupItemStateChangedEvent(topic, payload, itemName, memberName, state, oldState);
     }
 
-    private Event createCommandEvent(String topic, String payload, String source) {
+    private Event createCommandEvent(String topic, String payload, @Nullable String source) {
         String itemName = getItemName(topic);
         ItemEventPayloadBean bean = deserializePayload(payload, ItemEventPayloadBean.class);
         Command command = parseType(bean.getType(), bean.getValue(), Command.class);
         return new ItemCommandEvent(topic, payload, itemName, command, source);
     }
 
-    private Event createStateEvent(String topic, String payload, String source) {
+    private Event createStateEvent(String topic, String payload, @Nullable String source) {
         String itemName = getItemName(topic);
         ItemEventPayloadBean bean = deserializePayload(payload, ItemEventPayloadBean.class);
         State state = getState(bean.getType(), bean.getValue());
@@ -165,7 +167,7 @@ public class ItemEventFactory extends AbstractEventFactory {
         return desiredClass.cast(parsedObject);
     }
 
-    private Object parseSimpleClassName(String simpleClassName, String valueToParse) {
+    private @Nullable Object parseSimpleClassName(String simpleClassName, String valueToParse) {
         if (simpleClassName.equals(UnDefType.class.getSimpleName())) {
             return UnDefType.valueOf(valueToParse);
         }
@@ -176,7 +178,7 @@ public class ItemEventFactory extends AbstractEventFactory {
         try {
             Class<?> stateClass = Class.forName(CORE_LIBRARY_PACKAGE + simpleClassName);
             Method valueOfMethod = stateClass.getMethod("valueOf", String.class);
-            return valueOfMethod.invoke(null, valueToParse);
+            return valueOfMethod.invoke(stateClass, valueToParse);
         } catch (ClassNotFoundException e) {
             throw new IllegalArgumentException("Error getting class for simple name: '" + simpleClassName
                     + "' using package name '" + CORE_LIBRARY_PACKAGE + "'.", e);
@@ -217,7 +219,7 @@ public class ItemEventFactory extends AbstractEventFactory {
      * @return the created item command event
      * @throws IllegalArgumentException if itemName or command is null
      */
-    public static ItemCommandEvent createCommandEvent(String itemName, Command command, String source) {
+    public static ItemCommandEvent createCommandEvent(String itemName, Command command, @Nullable String source) {
         assertValidArguments(itemName, command, "command");
         String topic = buildTopic(ITEM_COMAND_EVENT_TOPIC, itemName);
         ItemEventPayloadBean bean = new ItemEventPayloadBean(getCommandType(command), command.toString());
@@ -246,7 +248,7 @@ public class ItemEventFactory extends AbstractEventFactory {
      * @return the created item state event
      * @throws IllegalArgumentException if itemName or state is null
      */
-    public static ItemStateEvent createStateEvent(String itemName, State state, String source) {
+    public static ItemStateEvent createStateEvent(String itemName, State state, @Nullable String source) {
         assertValidArguments(itemName, state, "state");
         String topic = buildTopic(ITEM_STATE_EVENT_TOPIC, itemName);
         ItemEventPayloadBean bean = new ItemEventPayloadBean(getStateType(state), state.toFullString());
@@ -415,8 +417,8 @@ public class ItemEventFactory extends AbstractEventFactory {
      * This is a java bean that is used to serialize/deserialize item event payload.
      */
     private static class ItemEventPayloadBean {
-        private String type;
+        private @NonNullByDefault({}) String type;
-        private String value;
+        private @NonNullByDefault({}) String value;
 
         /**
          * Default constructor for deserialization e.g. by Gson.
@@ -443,8 +445,8 @@ public class ItemEventFactory extends AbstractEventFactory {
      * This is a java bean that is used to serialize/deserialize item state changed event payload.
      */
     private static class ItemStatePredictedEventPayloadBean {
-        private String predictedType;
+        private @NonNullByDefault({}) String predictedType;
-        private String predictedValue;
+        private @NonNullByDefault({}) String predictedValue;
         private boolean isConfirmation;
 
         /**
@@ -477,10 +479,10 @@ public class ItemEventFactory extends AbstractEventFactory {
      * This is a java bean that is used to serialize/deserialize item state changed event payload.
      */
     private static class ItemStateChangedEventPayloadBean {
-        private String type;
+        private @NonNullByDefault({}) String type;
-        private String value;
+        private @NonNullByDefault({}) String value;
-        private String oldType;
+        private @NonNullByDefault({}) String oldType;
-        private String oldValue;
+        private @NonNullByDefault({}) String oldValue;
 
         /**
          * Default constructor for deserialization e.g. by Gson.

bundles/org.openhab.core/src/main/java/org/openhab/core/items/events/ItemRemovedEvent.java

@@ -12,6 +12,7 @@
  */
 package org.openhab.core.items.events;
 
+import org.eclipse.jdt.annotation.NonNullByDefault;
 import org.openhab.core.items.dto.ItemDTO;
 
 /**
@@ -20,6 +21,7 @@ import org.openhab.core.items.dto.ItemDTO;
  *
  * @author Stefan Bußweiler - Initial contribution
  */
+@NonNullByDefault
 public class ItemRemovedEvent extends AbstractItemRegistryEvent {
 
     /**

bundles/org.openhab.core/src/main/java/org/openhab/core/items/events/ItemUpdatedEvent.java

@@ -12,6 +12,7 @@
  */
 package org.openhab.core.items.events;
 
+import org.eclipse.jdt.annotation.NonNullByDefault;
 import org.openhab.core.items.dto.ItemDTO;
 
 /**
@@ -20,6 +21,7 @@ import org.openhab.core.items.dto.ItemDTO;
  *
  * @author Stefan Bußweiler - Initial contribution
  */
+@NonNullByDefault
 public class ItemUpdatedEvent extends AbstractItemRegistryEvent {
 
     private final ItemDTO oldItem;
@@ -49,7 +51,7 @@ public class ItemUpdatedEvent extends AbstractItemRegistryEvent {
 
     /**
      * Gets the old item.
-     * 
+     *
      * @return the oldItem
      */
     public ItemDTO getOldItem() {

bundles/org.openhab.core/src/test/java/org/openhab/core/events/AbstractEventFactoryTest.java

@@ -10,18 +10,20 @@
  *
  * SPDX-License-Identifier: EPL-2.0
  */
-package org.openhab.core.items.events;
+package org.openhab.core.events;
 
 import static org.junit.jupiter.api.Assertions.*;
 
+import org.eclipse.jdt.annotation.NonNullByDefault;
 import org.junit.jupiter.api.Test;
-import org.openhab.core.events.AbstractEventFactory;
+import org.openhab.core.items.events.ItemEventFactory;
 
 /**
- * {@link AbstractEventFactoryTests} tests the {@link AbstractEventFactory}.
+ * {@link AbstractEventFactoryTests} tests the {@link org.openhab.core.events.AbstractEventFactory}.
  *
  * @author Stefan Bußweiler - Initial contribution
  */
+@NonNullByDefault
 public class AbstractEventFactoryTest {
     private final ItemEventFactory factory = new ItemEventFactory();
 

bundles/org.openhab.core/src/test/java/org/openhab/core/items/events/ItemEventFactoryTest.java

@@ -16,6 +16,7 @@ import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.is;
 import static org.junit.jupiter.api.Assertions.*;
 
+import org.eclipse.jdt.annotation.NonNullByDefault;
 import org.junit.jupiter.api.Test;
 import org.openhab.core.events.Event;
 import org.openhab.core.items.Item;
@@ -36,6 +37,7 @@ import com.google.gson.Gson;
  *
  * @author Stefan Bußweiler - Initial contribution
  */
+@NonNullByDefault
 public class ItemEventFactoryTest {
     private final ItemEventFactory factory = new ItemEventFactory();
 

itests/org.openhab.core.automation.module.core.tests/src/main/java/org/openhab/core/automation/internal/module/RuntimeRuleTest.java

@@ -59,6 +59,7 @@ import org.openhab.core.library.types.OnOffType;
 import org.openhab.core.service.ReadyMarker;
 import org.openhab.core.test.java.JavaOSGiTest;
 import org.openhab.core.test.storage.VolatileStorageService;
+import org.openhab.core.types.Command;
 import org.openhab.core.types.TypeParser;
 import org.osgi.framework.ServiceReference;
 import org.slf4j.Logger;
@@ -417,8 +418,11 @@ public class RuntimeRuleTest extends JavaOSGiTest {
             final ItemRegistry itemRegistry = getService(ItemRegistry.class);
             final EventPublisher eventPublisher = getService(EventPublisher.class);
             final Item myMotionItem = itemRegistry.getItem("myMotionItem3");
-            eventPublisher.post(ItemEventFactory.createCommandEvent("myMotionItem3",
+            Command command = TypeParser.parseCommand(myMotionItem.getAcceptedCommandTypes(), "ON");
-                    TypeParser.parseCommand(myMotionItem.getAcceptedCommandTypes(), "ON")));
+            assertNotNull(command);
+            if (command != null) {
+                eventPublisher.post(ItemEventFactory.createCommandEvent("myMotionItem3", command));
+            }
 
             waitForAssert(() -> {
                 assertEquals(RuleStatusDetail.DISABLED, ruleEngine.getStatusInfo(firstRuleUID).getStatusDetail());
@@ -438,8 +442,11 @@ public class RuntimeRuleTest extends JavaOSGiTest {
                     .build();
             ruleRegistry.add(rule2);
 
-            eventPublisher.post(ItemEventFactory.createCommandEvent("myMotionItem3",
+            command = TypeParser.parseCommand(myMotionItem.getAcceptedCommandTypes(), "OFF");
-                    TypeParser.parseCommand(myMotionItem.getAcceptedCommandTypes(), "OFF")));
+            assertNotNull(command);
+            if (command != null) {
+                eventPublisher.post(ItemEventFactory.createCommandEvent("myMotionItem3", command));
+            }
 
             waitForAssert(() -> {
                 assertEquals(RuleStatus.IDLE, ruleEngine.getStatus(firstRuleUID));

itests/org.openhab.core.tests/src/main/java/org/openhab/core/internal/events/OSGiEventManagerOSGiTest.java

@@ -180,16 +180,6 @@ public class OSGiEventManagerOSGiTest extends JavaOSGiTest {
         assertEventCount(subscriber4, 0);
     }
 
-    @Test
-    public void testValidationEvent() {
-        try {
-            eventPublisher.post(null);
-            fail("IllegalArgumentException expected!");
-        } catch (IllegalArgumentException e) {
-            assertEquals("Argument 'event' must not be null.", e.getMessage());
-        }
-    }
-
     @Test
     public void testValidationType() {
         Event event = createEvent(null, "{a: 'A', b: 'B'}", TOPIC);