org.argeo.util/src/org/argeo/osgi/util/OsgiRegister.java

   1 package org.argeo.osgi.util;
   2
   3 import java.util.ArrayList;
   4 import java.util.Hashtable;
   5 import java.util.List;
   6 import java.util.Map;
   7 import java.util.concurrent.CompletableFuture;
   8 import java.util.concurrent.ExecutionException;
   9 import java.util.concurrent.Executor;
  10 import java.util.concurrent.ForkJoinPool;
  11
  12 import org.argeo.util.register.Register;
  13 import org.argeo.util.register.Singleton;
  14 import org.osgi.framework.BundleContext;
  15 import org.osgi.framework.ServiceRegistration;
  16
  17 public class OsgiRegister implements Register {
  18         private final BundleContext bundleContext;
  19         private Executor executor;
  20
  21         private CompletableFuture<Void> shutdownStarting = new CompletableFuture<Void>();
  22
  23         public OsgiRegister(BundleContext bundleContext) {
  24                 this.bundleContext = bundleContext;
  25                 // TODO experiment with dedicated executors
  26                 this.executor = ForkJoinPool.commonPool();
  27         }
  28
  29         @Override
  30         public <T> Singleton<T> set(T obj, Class<T> clss, Map<String, Object> attributes, Class<?>... classes) {
  31                 CompletableFuture<ServiceRegistration<?>> srf = new CompletableFuture<ServiceRegistration<?>>();
  32                 CompletableFuture<T> postRegistration = CompletableFuture.supplyAsync(() -> {
  33                         List<String> lst = new ArrayList<>();
  34                         lst.add(clss.getName());
  35                         for (Class<?> c : classes) {
  36                                 lst.add(c.getName());
  37                         }
  38                         ServiceRegistration<?> sr = bundleContext.registerService(lst.toArray(new String[lst.size()]), obj,
  39                                         new Hashtable<String, Object>(attributes));
  40                         srf.complete(sr);
  41                         return obj;
  42                 }, executor);
  43                 Singleton<T> singleton = new Singleton<T>(clss, postRegistration);
  44
  45                 shutdownStarting. //
  46                                 thenCompose(singleton::prepareUnregistration). //
  47                                 thenRunAsync(() -> {
  48                                         try {
  49                                                 srf.get().unregister();
  50                                         } catch (InterruptedException | ExecutionException e) {
  51                                                 e.printStackTrace();
  52                                         }
  53                                 }, executor);
  54                 return singleton;
  55         }
  56
  57         public void shutdown() {
  58                 shutdownStarting.complete(null);
  59         }
  60 }