Issue #6556 Use FuturePromise<SessionData>

Signed-off-by: Jan Bartel <janb@webtide.com>

jetty-memcached/jetty-memcached-sessions/src/main/java/org/eclipse/jetty/memcached/session/MemcachedSessionDataMap.java

@@ -21,11 +21,11 @@
 import net.rubyeye.xmemcached.MemcachedClient;
 import net.rubyeye.xmemcached.XMemcachedClientBuilder;
 import net.rubyeye.xmemcached.transcoders.SerializingTranscoder;
-import org.eclipse.jetty.server.session.RunnableResult;
 import org.eclipse.jetty.server.session.SessionContext;
 import org.eclipse.jetty.server.session.SessionData;
 import org.eclipse.jetty.server.session.SessionDataMap;
 import org.eclipse.jetty.util.ClassLoadingObjectInputStream;
+import org.eclipse.jetty.util.FuturePromise;
 import org.eclipse.jetty.util.annotation.ManagedAttribute;
 import org.eclipse.jetty.util.annotation.ManagedObject;
 import org.eclipse.jetty.util.component.AbstractLifeCycle;
@@ -164,17 +164,17 @@ public SessionData load(String id) throws Exception
         if (!isStarted())
             throw new IllegalStateException("Not started");
 
-        final RunnableResult<SessionData> result = new RunnableResult<>();
+        final FuturePromise<SessionData> result = new FuturePromise<>();
 
         Runnable r = () ->
         {
             try
             {
-                result.setResult(_client.get(id));
+                result.succeeded(_client.get(id));
             }
             catch (Exception e)
             {
-                result.setException(e);
+                result.failed(e);
             }
         };
 
@@ -188,20 +188,21 @@ public void store(String id, SessionData data) throws Exception
         if (!isStarted())
             throw new IllegalStateException("Not started");
 
-        final RunnableResult<Object> result = new RunnableResult<>();
+        final FuturePromise<Boolean> result = new FuturePromise<>();
         Runnable r = () ->
         {
             try
             {
                 _client.set(id, _expirySec, data);
+                result.succeeded(Boolean.TRUE);
             }
             catch (Exception e)
             {
-                result.setException(e);
+                result.failed(e);
             }
         };
         _context.run(r);
-        result.throwIfException();
+        result.getOrThrow();
     }
 
     @Override

jetty-server/src/main/java/org/eclipse/jetty/server/session/AbstractSessionDataStore.java

@@ -15,8 +15,10 @@
 
 import java.util.HashSet;
 import java.util.Set;
+import java.util.concurrent.ExecutionException;
 import java.util.concurrent.TimeUnit;
 
+import org.eclipse.jetty.util.FuturePromise;
 import org.eclipse.jetty.util.annotation.ManagedAttribute;
 import org.eclipse.jetty.util.annotation.ManagedObject;
 import org.eclipse.jetty.util.component.ContainerLifeCycle;
@@ -136,21 +138,22 @@ public SessionData load(String id) throws Exception
         if (!isStarted())
             throw new IllegalStateException("Not started");
 
-        final RunnableResult<SessionData> result = new RunnableResult<>();
-
+        final FuturePromise<SessionData> result = new FuturePromise<>();
+        
         Runnable r = () ->
         {
             try
             {
-                result.setResult(doLoad(id));
+                result.succeeded(doLoad(id));
             }
             catch (Exception e)
             {
-                result.setException(e);
+                result.failed(e);
             }
         };
 
         _context.run(r);
+
         return result.getOrThrow();
     }
 
@@ -179,40 +182,41 @@ public void store(String id, SessionData data) throws Exception
             //set the last saved time to now
             data.setLastSaved(System.currentTimeMillis());
 
-            final RunnableResult<Object> result = new RunnableResult<>();
+            final FuturePromise<Boolean> result = new FuturePromise<>();
             Runnable r = () ->
             {
                 try
                 {
                     //call the specific store method, passing in previous save time
                     doStore(id, data, lastSave);
                     data.clean(); //unset all dirty flags
+                    result.succeeded(Boolean.TRUE);
                 }
                 catch (Exception e)
                 {
                     //reset last save time if save failed
                     data.setLastSaved(lastSave);
-                    result.setException(e);
+                    result.failed(e);
                 }
             };
             _context.run(r);
-            result.throwIfException();
+            result.getOrThrow();
         }
     }
 
     @Override
     public boolean exists(String id) throws Exception
     {
-        RunnableResult<Boolean> result = new RunnableResult<>();
+        FuturePromise<Boolean> result = new FuturePromise<>();
         Runnable r = () ->
         {
             try
             {
-                result.setResult(doExists(id));
+                result.succeeded(doExists(id));
             }
             catch (Exception e)
             {
-                result.setException(e);
+                result.failed(e);
             }
         };
 

jetty-util/src/main/java/org/eclipse/jetty/util/FuturePromise.java

@@ -118,6 +118,27 @@ public C get() throws InterruptedException, ExecutionException
             throw (CancellationException)new CancellationException().initCause(_cause);
         throw new ExecutionException(_cause);
     }
+
+    /**
+     * Return the result if completed successfully
+     * or rethrow the Exception
+     * 
+     * @return the computed result
+     * @throws Exception
+     */
+    public C getOrThrow() throws Exception
+    {
+        _latch.await();
+
+        if (_cause == COMPLETED)
+            return _result;
+        if (_cause instanceof Exception)
+            throw (Exception)_cause;
+        if (_cause instanceof Error)
+            throw (Error)_cause;
+
+        throw new ExecutionException(_cause);
+    }
 
     @Override
     public C get(long timeout, TimeUnit unit) throws InterruptedException, ExecutionException, TimeoutException