package org.kuali.rice.ksb.impl.bus;

 import org.kuali.rice.ksb.api.bus.Endpoint;

 import org.kuali.rice.ksb.api.bus.ServiceConfiguration;

 import org.kuali.rice.ksb.messaging.serviceconnectors.ServiceConnectorFactory;

 public class LazyEndpoint implements Endpoint {

         private final Object lock = new Object();

         private final ServiceConfiguration serviceConfiguration;

         private volatile Object service;

         public LazyEndpoint(ServiceConfiguration serviceConfiguration) {

                 if (serviceConfiguration == null) {

                         throw new IllegalArgumentException("serviceConfiguration was null");

                 }

                 this.serviceConfiguration = serviceConfiguration;

         }

         @Override

         public ServiceConfiguration getServiceConfiguration() {

                 return this.serviceConfiguration;

         }

         @Override

         public Object getService() {

                 // double-checked locking idiom - see Effective Java, Item 71

                 Object internalService = this.service;

                 if (internalService == null) {

                         synchronized (lock) {

                                 internalService = this.service;

                                 if (internalService == null) {

                                         this.service = internalService = ServiceConnectorFactory.getServiceConnector(serviceConfiguration).getService(); 

                                 }

                         }

                 }

                 return internalService;

         }

 }