Fixing issues in plugin initialization as a result of certain plugins getting initialized after the device management component is done getting configured

components/device-mgt/org.wso2.carbon.device.mgt.core/src/main/java/org/wso2/carbon/device/mgt/core/internal/DeviceManagementServiceComponent.java

@@ -108,6 +108,7 @@ public class DeviceManagementServiceComponent {
     private static final Object LOCK = new Object();
     private boolean isInitialized;
     private List<DeviceManagementService> deviceManagementServices = new ArrayList<DeviceManagementService>();
+    private static List<PluginInitializationListener> listeners = new ArrayList<PluginInitializationListener>();
 
     protected void activate(ComponentContext componentContext) {
         try {
@@ -168,6 +169,10 @@ public class DeviceManagementServiceComponent {
         //do nothing
     }
 
+    public static void registerPluginInitializationListener(PluginInitializationListener listener) {
+        listeners.add(listener);
+    }
+
     private void initLicenseManager() throws LicenseManagementException {
         LicenseConfigurationManager.getInstance().initConfig();
         LicenseConfig licenseConfig =
@@ -242,6 +247,9 @@ public class DeviceManagementServiceComponent {
     private void registerDeviceManagementProvider(DeviceManagementService deviceManagementService) {
         try {
             this.getPluginRepository().addDeviceManagementProvider(deviceManagementService);
+            for (PluginInitializationListener listener : listeners) {
+                listener.notify(deviceManagementService);
+            }
         } catch (DeviceManagementException e) {
             log.error("Error occurred while adding device management provider '" +
                     deviceManagementService.getProviderType() + "'");

components/device-mgt/org.wso2.carbon.device.mgt.core/src/main/java/org/wso2/carbon/device/mgt/core/internal/PluginInitializationListener.java

@@ -0,0 +1,27 @@
+/*
+ *   Copyright (c) 2015, WSO2 Inc. (http://www.wso2.org) All Rights Reserved.
+ *
+ *   WSO2 Inc. licenses this file to you 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.
+ *
+ */
+package org.wso2.carbon.device.mgt.core.internal;
+
+import org.wso2.carbon.device.mgt.common.spi.DeviceManagementService;
+
+public interface PluginInitializationListener {
+
+    void notify(DeviceManagementService deviceManagementService);
+
+}

components/device-mgt/org.wso2.carbon.device.mgt.core/src/main/java/org/wso2/carbon/device/mgt/core/service/DeviceManagementProviderServiceImpl.java

@@ -26,6 +26,7 @@ import org.wso2.carbon.device.mgt.common.license.mgt.License;
 import org.wso2.carbon.device.mgt.common.license.mgt.LicenseManagementException;
 import org.wso2.carbon.device.mgt.common.operation.mgt.Operation;
 import org.wso2.carbon.device.mgt.common.operation.mgt.OperationManagementException;
+import org.wso2.carbon.device.mgt.common.spi.DeviceManagementService;
 import org.wso2.carbon.device.mgt.core.DeviceManagementRepository;
 import org.wso2.carbon.device.mgt.core.config.DeviceConfigurationManager;
 import org.wso2.carbon.device.mgt.core.config.email.NotificationMessages;
@@ -34,7 +35,9 @@ import org.wso2.carbon.device.mgt.core.dao.util.DeviceManagementDAOUtil;
 import org.wso2.carbon.device.mgt.core.dto.*;
 import org.wso2.carbon.device.mgt.core.email.EmailConstants;
 import org.wso2.carbon.device.mgt.core.internal.DeviceManagementDataHolder;
+import org.wso2.carbon.device.mgt.core.internal.DeviceManagementServiceComponent;
 import org.wso2.carbon.device.mgt.core.internal.EmailServiceDataHolder;
+import org.wso2.carbon.device.mgt.core.internal.PluginInitializationListener;
 import org.wso2.carbon.device.mgt.core.util.DeviceManagerUtil;
 
 import java.io.IOException;
@@ -43,7 +46,8 @@ import java.net.URLEncoder;
 import java.util.ArrayList;
 import java.util.List;
 
-public class DeviceManagementProviderServiceImpl implements DeviceManagementProviderService {
+public class DeviceManagementProviderServiceImpl implements
+        DeviceManagementProviderService, PluginInitializationListener {
 
     private DeviceDAO deviceDAO;
     private DeviceTypeDAO deviceTypeDAO;
@@ -53,6 +57,10 @@ public class DeviceManagementProviderServiceImpl implements DeviceManagementProv
     private static Log log = LogFactory.getLog(DeviceManagementProviderServiceImpl.class);
 
     public DeviceManagementProviderServiceImpl(DeviceManagementRepository pluginRepository) {
+        /* Registering a listener to retrieve events when some device management service plugin is installed after
+        * the component is done getting initialized */
+        DeviceManagementServiceComponent.registerPluginInitializationListener(this);
+
         this.pluginRepository = pluginRepository;
         this.deviceDAO = DeviceManagementDAOFactory.getDeviceDAO();
         this.deviceTypeDAO = DeviceManagementDAOFactory.getDeviceTypeDAO();
@@ -627,4 +635,14 @@ public class DeviceManagementProviderServiceImpl implements DeviceManagementProv
 
     }
 
+    @Override
+    public void notify(DeviceManagementService deviceManagementService) {
+        try {
+            pluginRepository.addDeviceManagementProvider(deviceManagementService);
+        } catch (DeviceManagementException e) {
+            log.error("Error occurred while registering device management plugin '" +
+                    deviceManagementService.getProviderType() + "'", e);
+        }
+    }
+
 }