Added transformation service support

README.md

@@ -486,6 +486,23 @@ Use case: Override logging for all rules defined in one file
 }
 ```
 
+## Example 23
+
+Use case: Apply transformation using openHAB transformation service
+
+```java
+   public class TransformationRule extends JRule {
+
+    @JRuleName("MyTransformation")
+    @JRuleWhen(item = _MyStringValue.ITEM, trigger = _MyStringValue.TRIGGER_RECEIVED_COMMAND)
+    public void applyTransformation(JRuleEvent event) {
+        String transformedValue = transform("MAP(my.map):%s", event.getValue());
+        logInfo("Transformed {} to {}", event.getValue(), transformedValue);
+        _MyTransformationReceiver.sendCommand(transformedValue);
+    }
+}
+```
+
 # Changelog
 ## BETA5
 - Addes support for adding rules in jar-files, as an alternative.

src/main/java/org/openhab/automation/jrule/internal/JRuleFactory.java

@@ -25,6 +25,7 @@
 import org.openhab.core.items.ItemRegistry;
 import org.openhab.core.voice.VoiceManager;
 import org.osgi.framework.FrameworkUtil;
+import org.osgi.service.component.ComponentContext;
 import org.osgi.service.component.annotations.Activate;
 import org.osgi.service.component.annotations.Component;
 import org.osgi.service.component.annotations.Deactivate;
@@ -63,7 +64,7 @@ public class JRuleFactory {
     @Activate
     public JRuleFactory(Map<String, Object> properties, final @Reference JRuleEventSubscriber eventSubscriber,
             final @Reference ItemRegistry itemRegistry, final @Reference EventPublisher eventPublisher,
-            final @Reference VoiceManager voiceManager) {
+            final @Reference VoiceManager voiceManager, final ComponentContext componentContext) {
         this.itemRegistry = itemRegistry;
         this.eventSubscriber = eventSubscriber;
         this.eventPublisher = eventPublisher;
@@ -72,7 +73,8 @@ public JRuleFactory(Map<String, Object> properties, final @Reference JRuleEventS
         config.initConfig();
         jRuleEngine = JRuleEngine.get();
         jRuleEngine.setConfig(config);
-        jRuleHandler = new JRuleHandler(config, itemRegistry, eventPublisher, eventSubscriber, voiceManager);
+        jRuleHandler = new JRuleHandler(properties, itemRegistry, eventPublisher, eventSubscriber, voiceManager,
+                componentContext.getBundleContext());
         createDelayedInitialization(getInitDelaySeconds(properties));
     }
 

src/main/java/org/openhab/automation/jrule/internal/handler/JRuleHandler.java

@@ -47,6 +47,7 @@
 import org.openhab.core.items.events.ItemRemovedEvent;
 import org.openhab.core.items.events.ItemUpdatedEvent;
 import org.openhab.core.voice.VoiceManager;
+import org.osgi.framework.BundleContext;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -72,6 +73,9 @@ public class JRuleHandler implements PropertyChangeListener {
     @NonNullByDefault({})
     private VoiceManager voiceManager;
 
+    @NonNullByDefault({})
+    private BundleContext bundleContext;
+
     private final Logger logger = LoggerFactory.getLogger(JRuleHandler.class);
 
     @Nullable
@@ -92,17 +96,21 @@ public class JRuleHandler implements PropertyChangeListener {
     private volatile boolean recompileJar = true;
 
     public JRuleHandler(JRuleConfig config, ItemRegistry itemRegistry, EventPublisher eventPublisher,
-            JRuleEventSubscriber eventSubscriber, VoiceManager voiceManager) {
+            JRuleEventSubscriber eventSubscriber, VoiceManager voiceManager, BundleContext bundleContext) {
         this.itemRegistry = itemRegistry;
         this.eventSubscriber = eventSubscriber;
         this.voiceManager = voiceManager;
         this.config = config;
+        this.bundleContext = bundleContext;
+
         JRuleEventHandler jRuleEventHandler = JRuleEventHandler.get();
         jRuleEventHandler.setEventPublisher(eventPublisher);
         jRuleEventHandler.setItemRegistry(itemRegistry);
         eventSubscriber.addPropertyChangeListener(this);
         JRuleVoiceHandler jRuleVoiceHandler = JRuleVoiceHandler.get();
         jRuleVoiceHandler.setVoiceManager(voiceManager);
+        JRuleTransformationHandler jRuleTransformationHandler = JRuleTransformationHandler.get();
+        jRuleTransformationHandler.setBundleContext(bundleContext);
         logDebug("JRuleHandler()");
     }
 

src/main/java/org/openhab/automation/jrule/internal/handler/JRuleTransformationHandler.java

@@ -0,0 +1,55 @@
+/**
+ * Copyright (c) 2010-2021 Contributors to the openHAB project
+ *
+ * See the NOTICE file(s) distributed with this work for additional
+ * information.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License 2.0 which is available at
+ * http://www.eclipse.org/legal/epl-2.0
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package org.openhab.automation.jrule.internal.handler;
+
+import org.openhab.core.transform.TransformationException;
+import org.openhab.core.transform.TransformationHelper;
+import org.osgi.framework.BundleContext;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * The {@link JRuleTransformationHandler} is responsible for handling transformation requests
+ *
+ * @author Arne Seime - Initial contribution
+ */
+public class JRuleTransformationHandler {
+
+    private static volatile JRuleTransformationHandler instance;
+
+    private BundleContext bundleContext;
+
+    private final Logger logger = LoggerFactory.getLogger(JRuleTransformationHandler.class);
+
+    private JRuleTransformationHandler() {
+    }
+
+    public static JRuleTransformationHandler get() {
+        if (instance == null) {
+            synchronized (JRuleTransformationHandler.class) {
+                if (instance == null) {
+                    instance = new JRuleTransformationHandler();
+                }
+            }
+        }
+        return instance;
+    }
+
+    public void setBundleContext(BundleContext bundleContext) {
+        this.bundleContext = bundleContext;
+    }
+
+    public String transform(String stateDescPattern, String state) throws TransformationException {
+        return TransformationHelper.transform(bundleContext, stateDescPattern, state);
+    }
+}

src/main/java/org/openhab/automation/jrule/rules/JRule.java

@@ -29,9 +29,11 @@
 import org.openhab.automation.jrule.internal.engine.JRuleEngine;
 import org.openhab.automation.jrule.internal.handler.JRuleActionHandler;
 import org.openhab.automation.jrule.internal.handler.JRuleEventHandler;
+import org.openhab.automation.jrule.internal.handler.JRuleTransformationHandler;
 import org.openhab.automation.jrule.internal.handler.JRuleVoiceHandler;
 import org.openhab.automation.jrule.items.JRulePercentType;
 import org.openhab.automation.jrule.rules.value.JRuleOnOffValue;
+import org.openhab.core.transform.TransformationException;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -165,6 +167,10 @@ protected void say(String text) {
         JRuleVoiceHandler.get().say(text);
     }
 
+    protected String transform(String stateDescPattern, String state) throws TransformationException {
+        return JRuleTransformationHandler.get().transform(stateDescPattern, state);
+    }
+
     protected void executeCommandLine(String... commandLine) {
         JRuleActionHandler.get().executeCommandLine(commandLine);
     }