Fixing license manager initialization related issues and code cleanup

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

@@ -17,46 +17,70 @@
  */
 package org.wso2.carbon.device.mgt.core;
 
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
 import org.wso2.carbon.device.mgt.common.DeviceManagementException;
 import org.wso2.carbon.device.mgt.common.spi.DeviceManagementService;
+import org.wso2.carbon.device.mgt.core.internal.DeviceManagementServiceComponent;
+import org.wso2.carbon.device.mgt.core.internal.DeviceManagerStartupListener;
 import org.wso2.carbon.device.mgt.core.util.DeviceManagerUtil;
 
-import java.util.Collection;
+import java.util.Collections;
 import java.util.HashMap;
 import java.util.Map;
 
-public class DeviceManagementPluginRepository {
+public class DeviceManagementPluginRepository implements DeviceManagerStartupListener {
 
     private Map<String, DeviceManagementService> providers;
+    private boolean isInited;
+    private static final Log log = LogFactory.getLog(DeviceManagementPluginRepository.class);
 
     public DeviceManagementPluginRepository() {
-        providers = new HashMap<String, DeviceManagementService>();
+        providers = Collections.synchronizedMap(new HashMap<String, DeviceManagementService>());
+        DeviceManagementServiceComponent.registerStartupListener(this);
     }
 
     public void addDeviceManagementProvider(DeviceManagementService provider) throws DeviceManagementException {
         String deviceType = provider.getType();
+        synchronized (providers) {
             try {
+                if (isInited) {
                     /* Initializing Device Management Service Provider */
                     provider.init();
                     DeviceManagerUtil.registerDeviceType(deviceType);
+                }
             } catch (DeviceManagementException e) {
                 throw new DeviceManagementException("Error occurred while adding device management provider '" +
-                    deviceType + "'");
+                        deviceType + "'", e);
             }
             providers.put(deviceType, provider);
         }
+    }
 
     public void removeDeviceManagementProvider(DeviceManagementService provider) throws DeviceManagementException {
-        String deviceType = provider.getType();
-        providers.remove(deviceType);
+        providers.remove(provider.getType());
     }
 
     public DeviceManagementService getDeviceManagementService(String type) {
         return providers.get(type);
     }
 
-    public Collection<DeviceManagementService> getDeviceManagementProviders(){
-        return providers.values();
+    @Override
+    public void notifyObserver() {
+        synchronized (providers) {
+            for (DeviceManagementService provider : providers.values()) {
+                try {
+                    provider.init();
+                    DeviceManagerUtil.registerDeviceType(provider.getType());
+                } catch (Throwable e) {
+                    /* Throwable is caught intentionally as failure of one plugin - due to invalid start up parameters,
+                        etc - should not block the initialization of other device management providers */
+                    log.error("Error occurred while initializing device management provider '" +
+                            provider.getType() + "'", e);
+                }
+            }
+            this.isInited = true;
+        }
     }
 
 }

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

@@ -95,8 +95,9 @@ public class DeviceManagementServiceComponent {
     private DeviceManagementPluginRepository pluginRepository = new DeviceManagementPluginRepository();
 
     private static final Object LOCK = new Object();
-    private static List<PluginInitializationListener> listeners = new ArrayList<PluginInitializationListener>();
-    private static List<DeviceManagementService> deviceManagers = new ArrayList<DeviceManagementService>();
+    private static List<PluginInitializationListener> listeners = new ArrayList<>();
+    private static List<DeviceManagementService> deviceManagers = new ArrayList<>();
+    private static List<DeviceManagerStartupListener> startupListeners = new ArrayList<>();
 
     @SuppressWarnings("unused")
     protected void activate(ComponentContext componentContext) {
@@ -130,6 +131,9 @@ public class DeviceManagementServiceComponent {
             /* Registering declarative service instances exposed by DeviceManagementServiceComponent */
             this.registerServices(componentContext);
 
+            /* This is a workaround to initialize all Device Management Service Providers after the initialization
+             * of Device Management Service component in order to avoid bundle start up order related complications */
+            notifyStartupListeners();
             if (log.isDebugEnabled()) {
                 log.debug("Device management core bundle has been successfully initialized");
             }
@@ -312,4 +316,14 @@ public class DeviceManagementServiceComponent {
         DeviceManagementDataHolder.getInstance().setConfigurationContextService(null);
     }
 
+    public static void registerStartupListener(DeviceManagerStartupListener startupListener) {
+        startupListeners.add(startupListener);
+    }
+
+    public static void notifyStartupListeners() {
+        for (DeviceManagerStartupListener startupListener : startupListeners) {
+            startupListener.notifyObserver();
+        }
+    }
+
 }

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

@@ -16,10 +16,10 @@
  *   under the License.
  *
  */
-package org.wso2.carbon.device.mgt.extensions.license.mgt;
-
-public class LicenseManagementUtil {
+package org.wso2.carbon.device.mgt.core.internal;
 
+public interface DeviceManagerStartupListener {
 
+    void notifyObserver();
 
 }

components/device-mgt/org.wso2.carbon.device.mgt.extensions/pom.xml

@@ -56,6 +56,16 @@
                         <Export-Package>
                             org.wso2.carbon.device.mgt.extensions.*
                         </Export-Package>
+                        <Import-Package>
+                            org.wso2.carbon.governance.api.*,
+                            javax.xml.namespace,
+                            org.wso2.carbon.context,
+                            org.wso2.carbon.device.mgt.common.license.mgt,
+                            org.wso2.carbon.registry.api,
+                            org.wso2.carbon.registry.core,
+                            org.wso2.carbon.registry.core.exceptions,
+                            org.wso2.carbon.registry.core.session
+                        </Import-Package>
                     </instructions>
                 </configuration>
             </plugin>

components/device-mgt/org.wso2.carbon.device.mgt.extensions/src/main/java/org/wso2/carbon/device/mgt/extensions/license/mgt/GenericArtifactManagerFactory.java

@@ -22,8 +22,10 @@ import org.wso2.carbon.context.CarbonContext;
 import org.wso2.carbon.device.mgt.common.DeviceManagementConstants;
 import org.wso2.carbon.device.mgt.common.license.mgt.LicenseManagementException;
 import org.wso2.carbon.governance.api.generic.GenericArtifactManager;
+import org.wso2.carbon.governance.api.util.GovernanceUtils;
 import org.wso2.carbon.registry.api.Registry;
 import org.wso2.carbon.registry.core.exceptions.RegistryException;
+import org.wso2.carbon.registry.core.session.UserRegistry;
 
 import java.util.HashMap;
 import java.util.Map;
@@ -32,14 +34,14 @@ public class GenericArtifactManagerFactory {
 
     private static Map<Integer, GenericArtifactManager> tenantArtifactManagers =
             new HashMap<Integer, GenericArtifactManager>();
-    private static final Object lock = new Object();
+    private static final Object LOCK = new Object();
 
     public static GenericArtifactManager getTenantAwareGovernanceArtifactManager(
             Registry registry) throws LicenseManagementException {
         try {
             int tenantId = CarbonContext.getThreadLocalCarbonContext().getTenantId();
             GenericArtifactManager artifactManager;
-            synchronized (lock) {
+            synchronized (LOCK) {
                 artifactManager =
                         tenantArtifactManagers.get(tenantId);
                 if (artifactManager == null) {
@@ -54,7 +56,7 @@ public class GenericArtifactManagerFactory {
             return artifactManager;
         } catch (RegistryException e) {
             throw new LicenseManagementException("Error occurred while initializing GovernanceArtifactManager " +
-                    "associated with tenant '" + CarbonContext.getThreadLocalCarbonContext().getTenantDomain() + "'");
+                    "associated with tenant '" + CarbonContext.getThreadLocalCarbonContext().getTenantDomain() + "'", e);
         }
     }
 

components/device-mgt/org.wso2.carbon.device.mgt.extensions/src/main/java/org/wso2/carbon/device/mgt/extensions/license/mgt/LicenseManagementService.java

@@ -1,38 +0,0 @@
-/*
- *   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.extensions.license.mgt;
-
-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.license.mgt.LicenseManager;
-
-public class LicenseManagementService implements LicenseManager {
-
-    @Override
-    public License getLicense(String deviceType, String languageCode) throws LicenseManagementException {
-        //return DeviceManagementDataHolder.getInstance().getLicenseManager().getLicense(deviceType, languageCode);
-        return null;
-    }
-
-    @Override
-    public void addLicense(String deviceType, License license) throws LicenseManagementException {
-        //return DeviceManagementDataHolder.getInstance().getLicenseManager().addLicense(deviceType, license);
-    }
-
-}

components/device-mgt/org.wso2.carbon.device.mgt.extensions/src/main/java/org/wso2/carbon/device/mgt/extensions/license/mgt/RegistryBasedLicenseManager.java

@@ -19,6 +19,8 @@
 
 package org.wso2.carbon.device.mgt.extensions.license.mgt;
 
+import org.wso2.carbon.context.CarbonContext;
+import org.wso2.carbon.context.RegistryType;
 import org.wso2.carbon.device.mgt.common.DeviceManagementConstants;
 import org.wso2.carbon.device.mgt.common.license.mgt.License;
 import org.wso2.carbon.device.mgt.common.license.mgt.LicenseManagementException;
@@ -41,9 +43,10 @@ public class RegistryBasedLicenseManager implements LicenseManager {
     private Registry registry;
     private GenericArtifactManager artifactManager;
 
-    public RegistryBasedLicenseManager(Registry registry) {
+    public RegistryBasedLicenseManager() {
+        Registry registry = CarbonContext.getThreadLocalCarbonContext().getRegistry(RegistryType.SYSTEM_GOVERNANCE);
         if (registry == null) {
-            throw new IllegalArgumentException("Registry instance provided is null. Hence, " +
+            throw new IllegalArgumentException("Registry instance retrieved is null. Hence, " +
                     "'Registry based license manager cannot be initialized'");
         }
         this.registry = registry;