1 files changed, 76 insertions, 0 deletions
diff --git a/services/services-engine/src/main/java/org/onap/policy/apex/service/engine/event/impl/EventProtocolFactory.java b/services/services-engine/src/main/java/org/onap/policy/apex/service/engine/event/impl/EventProtocolFactory.java
new file mode 100644
index 000000000..85c5bf03f
--- /dev/null
+++ b/services/services-engine/src/main/java/org/onap/policy/apex/service/engine/event/impl/EventProtocolFactory.java
@@ -0,0 +1,76 @@
+/*-
+ * ============LICENSE_START=======================================================
+ *  Copyright (C) 2016-2018 Ericsson. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * 
+ * SPDX-License-Identifier: Apache-2.0
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.policy.apex.service.engine.event.impl;
+
+import org.onap.policy.apex.service.engine.event.ApexEventProtocolConverter;
+import org.onap.policy.apex.service.engine.event.ApexEventRuntimeException;
+import org.onap.policy.apex.service.parameters.eventprotocol.EventProtocolParameters;
+import org.slf4j.ext.XLogger;
+import org.slf4j.ext.XLoggerFactory;
+
+/**
+ * This factory class uses the Apex event protocol parameters to create and return an instance of
+ * the correct Apex event protocol converter plugin for the specified event protocol.
+ *
+ * @author Liam Fallon (liam.fallon@ericsson.com)
+ */
+public class EventProtocolFactory {
+    // The logger for this class
+    private static final XLogger LOGGER = XLoggerFactory.getXLogger(EventProtocolFactory.class);
+
+    /**
+     * Create an event converter that converts between an
+     * {@link org.onap.policy.apex.service.engine.event.ApexEvent} and the specified event protocol.
+     *
+     * @param name the name of the event protocol
+     * @param eventProtocolParameters the event protocol parameters defining what to convert from
+     *        and to
+     * @return The event converter for converting events to and from Apex format
+     */
+    public ApexEventProtocolConverter createConverter(final String name,
+            final EventProtocolParameters eventProtocolParameters) {
+        // Get the class for the event protocol plugin using reflection
+        final String eventProtocolPluginClass = eventProtocolParameters.getEventProtocolPluginClass();
+        Object eventProtocolPluginObject = null;
+        try {
+            eventProtocolPluginObject = Class.forName(eventProtocolPluginClass).newInstance();
+        } catch (InstantiationException | IllegalAccessException | ClassNotFoundException e) {
+            final String errorMessage = "could not create an Apex event protocol converter for \"" + name
+                    + "\" for the protocol \"" + eventProtocolParameters.getLabel()
+                    + "\", specified event protocol converter plugin class \"" + eventProtocolPluginClass
+                    + "\" not found";
+            LOGGER.error(errorMessage, e);
+            throw new ApexEventRuntimeException(errorMessage, e);
+        }
+
+        // Check the class is an event consumer
+        if (!(eventProtocolPluginObject instanceof ApexEventProtocolConverter)) {
+            final String errorMessage = "could not create an Apex event protocol converter for \"" + name
+                    + "\" for the protocol \"" + eventProtocolParameters.getLabel()
+                    + "\", specified event protocol converter plugin class \"" + eventProtocolPluginClass
+                    + "\" is not an instance of \"" + ApexEventProtocolConverter.class.getCanonicalName() + "\"";
+            LOGGER.error(errorMessage);
+            throw new ApexEventRuntimeException(errorMessage);
+        }
+        ((ApexEventProtocolConverter) eventProtocolPluginObject).init(eventProtocolParameters);
+        return (ApexEventProtocolConverter) eventProtocolPluginObject;
+    }
+}