001 package de.deepamehta.core.osgi;
002
003 import de.deepamehta.core.impl.EmbeddedService;
004 import de.deepamehta.core.impl.StorageDecorator;
005 import de.deepamehta.core.impl.WebPublishingService;
006 import de.deepamehta.core.service.DeepaMehtaService;
007 import de.deepamehta.core.storage.spi.DeepaMehtaStorage;
008
009 import org.osgi.framework.BundleActivator;
010 import org.osgi.framework.BundleContext;
011 import org.osgi.framework.ServiceReference;
012 import org.osgi.service.http.HttpService;
013 import org.osgi.util.tracker.ServiceTracker;
014
015 import java.util.logging.Logger;
016
017
018
019 public class CoreActivator implements BundleActivator {
020
021 // ------------------------------------------------------------------------------------------------------- Constants
022
023 private static final String DATABASE_PATH = System.getProperty("dm4.database.path");
024
025 // ---------------------------------------------------------------------------------------------- Instance Variables
026
027 private BundleContext bundleContext;
028
029 // consumed services
030 private DeepaMehtaStorage storageService;
031 private HttpService httpService;
032
033 private ServiceTracker storageServiceTracker;
034 private ServiceTracker httpServiceTracker;
035
036 private Logger logger = Logger.getLogger(getClass().getName());
037
038 // -------------------------------------------------------------------------------------------------- Public Methods
039
040
041
042 // **************************************
043 // *** BundleActivator Implementation ***
044 // **************************************
045
046
047
048 @Override
049 public void start(BundleContext bundleContext) {
050 try {
051 logger.info("========== Starting \"DeepaMehta 4 Core\" ==========");
052 this.bundleContext = bundleContext;
053 //
054 storageServiceTracker = createServiceTracker(DeepaMehtaStorage.class);
055 httpServiceTracker = createServiceTracker(HttpService.class);
056 //
057 storageServiceTracker.open();
058 httpServiceTracker.open();
059 } catch (Exception e) {
060 logger.severe("Starting \"DeepaMehta 4 Core\" failed:");
061 e.printStackTrace();
062 // Note: we don't throw through the OSGi container here. It would not print out the stacktrace.
063 // File Install would retry to start the bundle endlessly.
064 }
065 }
066
067 @Override
068 public void stop(BundleContext bundleContext) {
069 try {
070 logger.info("========== Stopping \"DeepaMehta 4 Core\" ==========");
071 storageServiceTracker.close();
072 httpServiceTracker.close();
073 //
074 // Note: we do not shutdown the DB here.
075 // The DB shuts down itself through the storage bundle's stop() method.
076 } catch (Exception e) {
077 logger.severe("Stopping \"DeepaMehta 4 Core\" failed:");
078 e.printStackTrace();
079 // Note: we don't throw through the OSGi container here. It would not print out the stacktrace.
080 }
081 }
082
083
084
085 // ------------------------------------------------------------------------------------------------- Private Methods
086
087 private ServiceTracker createServiceTracker(Class serviceInterface) {
088 //
089 return new ServiceTracker(bundleContext, serviceInterface.getName(), null) {
090
091 @Override
092 public Object addingService(ServiceReference serviceRef) {
093 // ### TODO: should we catch exceptions here?
094 // ### If HttpService is available on open() the exception is catched in start() -> OK.
095 // ### If HttpService is not available on open() the exception is thrown through the OSGi container
096 // ### and the stacktrace is not logged.
097 Object service = null;
098 try {
099 service = super.addingService(serviceRef);
100 addService(service);
101 } catch (Exception e) {
102 logger.severe("Adding service " + service + " to \"DeepaMehta 4 Core\" failed:");
103 e.printStackTrace();
104 // Note: we don't throw through the OSGi container here. It would not print out the stacktrace.
105 }
106 return service;
107 }
108
109 @Override
110 public void removedService(ServiceReference ref, Object service) {
111 try {
112 removeService(service);
113 super.removedService(ref, service);
114 } catch (Exception e) {
115 logger.severe("Removing service " + service + " from \"DeepaMehta 4 Core\" failed:");
116 e.printStackTrace();
117 // Note: we don't throw through the OSGi container here. It would not print out the stacktrace.
118 }
119 }
120 };
121 }
122
123 // ---
124
125 private void addService(Object service) {
126 if (service instanceof DeepaMehtaStorage) {
127 logger.info("Adding storage service to DeepaMehta 4 Core");
128 storageService = (DeepaMehtaStorage) service;
129 checkRequirementsForActivation();
130 } else if (service instanceof HttpService) {
131 logger.info("Adding HTTP service to DeepaMehta 4 Core");
132 httpService = (HttpService) service;
133 checkRequirementsForActivation();
134 }
135 }
136
137 private void removeService(Object service) {
138 if (service == storageService) {
139 logger.info("Removing storage service from DeepaMehta 4 Core");
140 storageService = null;
141 } else if (service == httpService) {
142 logger.info("Removing HTTP service from DeepaMehta 4 Core");
143 // ### TODO: unregister WebPublishingService
144 httpService = null;
145 }
146 }
147
148 // ---
149
150 private void checkRequirementsForActivation() {
151 if (storageService != null && httpService != null) {
152 EmbeddedService dms = new EmbeddedService(new StorageDecorator(storageService), bundleContext);
153 logger.info("Registering DeepaMehta 4 core service at OSGi framework");
154 bundleContext.registerService(DeepaMehtaService.class.getName(), dms, null);
155 //
156 WebPublishingService wpService = new WebPublishingService(dms, httpService);
157 logger.info("Registering Web Publishing service at OSGi framework");
158 bundleContext.registerService(WebPublishingService.class.getName(), wpService, null);
159 }
160 }
161 }