Made it easier to export serivice.s

slingtests/osgikernel/bundles/db/src/main/java/org/sakaiproject/kernel/persistence/Activator.java

@@ -18,9 +18,8 @@
 package org.sakaiproject.kernel.persistence;
 
 
-import com.google.inject.Module;
-
 import org.osgi.framework.BundleContext;
+import org.sakaiproject.kernel.guice.AbstractOsgiModule;
 import org.sakaiproject.kernel.guice.GuiceActivator;
 
 /**
@@ -33,7 +32,7 @@ public class Activator extends GuiceActivator {
    * @see org.sakaiproject.kernel.guice.GuiceActivator#getModule()
    */
   @Override
-  protected Module getModule(BundleContext bundleContext) {
+  protected AbstractOsgiModule getModule(BundleContext bundleContext) {
     return new ActivatorModule(bundleContext);
   }
 

slingtests/osgikernel/bundles/db/src/main/java/org/sakaiproject/kernel/persistence/ActivatorModule.java

@@ -24,14 +24,10 @@
 import org.sakaiproject.kernel.api.memory.CacheManagerService;
 import org.sakaiproject.kernel.api.persistence.DataSourceService;
 import org.sakaiproject.kernel.guice.AbstractOsgiModule;
-import org.sakaiproject.kernel.guice.OsgiServiceProvider;
-import org.sakaiproject.kernel.guice.ServiceExportList;
 import org.sakaiproject.kernel.persistence.dbcp.DataSourceServiceImpl;
 import org.sakaiproject.kernel.persistence.eclipselink.EntityManagerFactoryProvider;
 import org.sakaiproject.kernel.persistence.geronimo.TransactionManagerProvider;
 
-import java.util.List;
-
 import javax.persistence.EntityManager;
 import javax.persistence.EntityManagerFactory;
 import javax.sql.DataSource;
@@ -64,24 +60,24 @@ protected void configure() {
     bind(EntityManagerFactory.class).toProvider(
         EntityManagerFactoryProvider.class).in(Scopes.SINGLETON);
     // bind the EntityManager to a ScopedEntityManger
-    bind(EntityManager.class).to(ScopedEntityManager.class)
+    bind(export(EntityManager.class)).to(ScopedEntityManager.class)
         .in(Scopes.SINGLETON);
     // Bind in the datasource
-    bind(DataSource.class).toProvider(DataSourceServiceImpl.class).in(
+    bind(export(DataSource.class)).toProvider(DataSourceServiceImpl.class).in(
         Scopes.SINGLETON);
     // and the transaction manager via a provider.
-    bind(TransactionManager.class).toProvider(TransactionManagerProvider.class)
+    bind(export(TransactionManager.class)).toProvider(TransactionManagerProvider.class)
         .in(Scopes.SINGLETON);
 
     // bind the services
     bind(DataSourceService.class).to(DataSourceServiceImpl.class).in(
         Scopes.SINGLETON);
 
-    bind(CacheManagerService.class).toProvider(new OsgiServiceProvider<CacheManagerService>(CacheManagerService.class,bundleContext));
+    bind(CacheManagerService.class).toProvider(importService(CacheManagerService.class).asSingleton());
 
-    bind(List.class).annotatedWith(ServiceExportList.class).toProvider(ServiceExportProvider.class);
   }
 
+
   /**
    * {@inheritDoc}
    * @see org.sakaiproject.kernel.guice.AbstractOsgiModule#getBundleContext()

slingtests/osgikernel/bundles/guice/src/main/java/org/sakaiproject/kernel/guice/AbstractOsgiModule.java

@@ -17,6 +17,7 @@
  */
 package org.sakaiproject.kernel.guice;
 
+import com.google.common.collect.Sets;
 import com.google.inject.AbstractModule;
 import com.google.inject.name.Names;
 
@@ -26,13 +27,15 @@
 import org.slf4j.LoggerFactory;
 
 import java.util.Map;
+import java.util.Set;
 
 /**
  * Provides configuration support.
  */
 public abstract class AbstractOsgiModule extends AbstractModule {
 
   private static final Logger LOGGER = LoggerFactory.getLogger(AbstractOsgiModule.class);
+  private Set<Class<?>> exports = Sets.newHashSet();
 
   /**
    * {@inheritDoc}
@@ -55,4 +58,31 @@ protected void configure() {
    */
   protected abstract BundleContext getBundleContext();
 
+
+  /**
+   * @param class1
+   * @return
+   */
+  protected <T> Class<T> export(Class<T> clazz) {
+    exports.add(clazz);
+    return clazz;
+  }
+
+  /**
+   * @param class1
+   * @return
+   */
+  protected <T> OsgiServiceProvider<T> importService(Class<T> class1) {
+    return new OsgiServiceProvider<T>(class1,getBundleContext());
+  }
+
+
+
+  /**
+   * @return the exports
+   */
+  public Set<Class<?>> getExports() {
+    return exports;
+  }
+
 }

slingtests/osgikernel/bundles/guice/src/main/java/org/sakaiproject/kernel/guice/GuiceActivator.java

@@ -20,16 +20,13 @@
 import com.google.common.collect.Sets;
 import com.google.inject.Guice;
 import com.google.inject.Injector;
-import com.google.inject.Key;
-import com.google.inject.Module;
 
 import org.osgi.framework.BundleActivator;
 import org.osgi.framework.BundleContext;
 import org.osgi.framework.Constants;
 
 import java.util.Dictionary;
 import java.util.Hashtable;
-import java.util.List;
 import java.util.Set;
 
 /**
@@ -41,20 +38,22 @@
 public abstract class GuiceActivator implements BundleActivator {
 
   private Injector injector;
-  private List<?> services;
+  private Set<Class<?>> services;
 
   /**
    * {@inheritDoc}
    * 
    * @see org.osgi.framework.BundleActivator#start(org.osgi.framework.BundleContext)
    */
   public void start(BundleContext bundleContext) throws Exception {
-    injector = Guice.createInjector(getModule(bundleContext));
+    AbstractOsgiModule module = getModule(bundleContext);
+    injector = Guice.createInjector(module);
 
-    services = injector.getInstance(Key.get(List.class, ServiceExportList.class));
-    for (Object o : services) {
-      if (o.getClass().isAnnotationPresent(ServiceExportDescription.class)) {
-        ServiceExportDescription ks = o.getClass().getAnnotation(
+    services = module.getExports();
+    for (Class<?> serviceClass : services) {
+      Object service = injector.getInstance(serviceClass);
+      if (serviceClass.isAnnotationPresent(ServiceExportDescription.class)) {
+        ServiceExportDescription ks = serviceClass.getAnnotation(
             ServiceExportDescription.class);
         Dictionary<String, Object> dictionary = new Hashtable<String, Object>();
         Class<?>[] serviceClasses = ks.serviceClasses();
@@ -66,13 +65,13 @@ public void start(BundleContext bundleContext) throws Exception {
         dictionary.put(Constants.OBJECTCLASS, serviceClassNames);
         dictionary.put(Constants.SERVICE_DESCRIPTION, ks.serviceDescription());
         dictionary.put(Constants.SERVICE_VENDOR, ks.seviceVendor());
-        bundleContext.registerService(serviceClassNames, o, dictionary);
+        bundleContext.registerService(serviceClassNames, service, dictionary);
       } else {
-        Class<?>[] implementedInterfaces = o.getClass().getInterfaces();
-        o.getClass().isInterface();
+        Class<?>[] implementedInterfaces = serviceClass.getInterfaces();
+        serviceClass.isInterface();
         Set<Class<?>> interfaces = Sets.newHashSet();
-        if (o.getClass().isInterface()) {
-          interfaces.add(o.getClass());
+        if (serviceClass.isInterface()) {
+          interfaces.add(serviceClass);
         }
         for (Class<?> c : implementedInterfaces) {
           interfaces.add(c);
@@ -84,9 +83,9 @@ public void start(BundleContext bundleContext) throws Exception {
           serviceClassNames[i++] = c.getName();
         }
         dictionary.put(Constants.OBJECTCLASS, serviceClassNames);
-        dictionary.put(Constants.SERVICE_DESCRIPTION, o.getClass().getName());
+        dictionary.put(Constants.SERVICE_DESCRIPTION, serviceClass.getName());
         dictionary.put(Constants.SERVICE_VENDOR, "The Sakai Foundation");
-        bundleContext.registerService(serviceClassNames, o, dictionary);
+        bundleContext.registerService(serviceClassNames, service, dictionary);
       }
     }
   }
@@ -107,6 +106,6 @@ public void stop(BundleContext bundleContext) throws Exception {
   /**
    * @return
    */
-  protected abstract Module getModule(BundleContext bundleContext);
+  protected abstract AbstractOsgiModule getModule(BundleContext bundleContext);
 
 }

slingtests/osgikernel/bundles/guice/src/main/java/org/sakaiproject/kernel/guice/OsgiServiceProvider.java

@@ -25,31 +25,55 @@
 /**
  * Create a generic Guice provider that binds to a service in OSGi
  */
-public class OsgiServiceProvider<T> implements
-    Provider<T> {
+public class OsgiServiceProvider<T> implements Provider<T> {
 
   private BundleContext bundleContext;
   private ServiceReference serviceReference;
+  private boolean singleton = false;
+  private T service;
+  private Object serviceLock = new Object();;
 
   /**
-   * @param the interface representing the service
-   * @param bundleContext the bundle context of this bundle
+   * @param the
+   *          interface representing the service
+   * @param bundleContext
+   *          the bundle context of this bundle
    */
-  public OsgiServiceProvider(Class<T> serviceClass,
-      BundleContext bundleContext) {
+  public OsgiServiceProvider(Class<T> serviceClass, BundleContext bundleContext) {
     this.bundleContext = bundleContext;
-    // convert the service class into a reference, since the provision of the service class 
+    // convert the service class into a reference, since the provision of the service
+    // class
     // may change.
     this.serviceReference = bundleContext.getServiceReference(serviceClass.getName());
   }
 
   /**
    * {@inheritDoc}
+   * 
    * @see com.google.inject.Provider#get()
    */
   @SuppressWarnings("unchecked")
   public T get() {
-    return (T) bundleContext.getService(serviceReference);
+    if (singleton) {
+      if (service == null) {
+        synchronized (serviceLock) {
+          if (service == null) {
+            service = (T) bundleContext.getService(serviceReference);
+          }
+        }
+      }
+      return service;
+    } else {
+      return (T) bundleContext.getService(serviceReference);
+    }
+  }
+
+  /**
+   * @return
+   */
+  public OsgiServiceProvider<T> asSingleton() {
+    singleton = true;
+    return this;
   }
 
 }