| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You under the Apache License, Version 2.0 |
| * (the "License"); you may not use this file except in compliance with |
| * the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package org.apache.spark.launcher; |
| |
| import java.io.IOException; |
| import java.util.List; |
| import java.util.concurrent.CopyOnWriteArrayList; |
| import java.util.concurrent.atomic.AtomicReference; |
| import java.util.logging.Level; |
| import java.util.logging.Logger; |
| |
| abstract class AbstractAppHandle implements SparkAppHandle { |
| |
| private static final Logger LOG = Logger.getLogger(AbstractAppHandle.class.getName()); |
| |
| private final LauncherServer server; |
| |
| private LauncherServer.ServerConnection connection; |
| private List<Listener> listeners; |
| private AtomicReference<State> state; |
| private volatile String appId; |
| private volatile boolean disposed; |
| |
| protected AbstractAppHandle(LauncherServer server) { |
| this.server = server; |
| this.state = new AtomicReference<>(State.UNKNOWN); |
| } |
| |
| @Override |
| public synchronized void addListener(Listener l) { |
| if (listeners == null) { |
| listeners = new CopyOnWriteArrayList<>(); |
| } |
| listeners.add(l); |
| } |
| |
| @Override |
| public State getState() { |
| return state.get(); |
| } |
| |
| @Override |
| public String getAppId() { |
| return appId; |
| } |
| |
| @Override |
| public void stop() { |
| CommandBuilderUtils.checkState(connection != null, "Application is still not connected."); |
| try { |
| connection.send(new LauncherProtocol.Stop()); |
| } catch (IOException ioe) { |
| throw new RuntimeException(ioe); |
| } |
| } |
| |
| @Override |
| public synchronized void disconnect() { |
| if (connection != null && connection.isOpen()) { |
| try { |
| connection.close(); |
| } catch (IOException ioe) { |
| // no-op. |
| } |
| } |
| dispose(); |
| } |
| |
| void setConnection(LauncherServer.ServerConnection connection) { |
| this.connection = connection; |
| } |
| |
| LauncherConnection getConnection() { |
| return connection; |
| } |
| |
| boolean isDisposed() { |
| return disposed; |
| } |
| |
| /** |
| * Mark the handle as disposed, and set it as LOST in case the current state is not final. |
| * |
| * This method should be called only when there's a reasonable expectation that the communication |
| * with the child application is not needed anymore, either because the code managing the handle |
| * has said so, or because the child application is finished. |
| */ |
| synchronized void dispose() { |
| if (!isDisposed()) { |
| // First wait for all data from the connection to be read. Then unregister the handle. |
| // Otherwise, unregistering might cause the server to be stopped and all child connections |
| // to be closed. |
| if (connection != null) { |
| try { |
| connection.waitForClose(); |
| } catch (IOException ioe) { |
| // no-op. |
| } |
| } |
| server.unregister(this); |
| |
| // Set state to LOST if not yet final. |
| setState(State.LOST, false); |
| this.disposed = true; |
| } |
| } |
| |
| void setState(State s) { |
| setState(s, false); |
| } |
| |
| void setState(State s, boolean force) { |
| if (force) { |
| state.set(s); |
| fireEvent(false); |
| return; |
| } |
| |
| State current = state.get(); |
| while (!current.isFinal()) { |
| if (state.compareAndSet(current, s)) { |
| fireEvent(false); |
| return; |
| } |
| current = state.get(); |
| } |
| |
| if (s != State.LOST) { |
| LOG.log(Level.WARNING, "Backend requested transition from final state {0} to {1}.", |
| new Object[] { current, s }); |
| } |
| } |
| |
| void setAppId(String appId) { |
| this.appId = appId; |
| fireEvent(true); |
| } |
| |
| private void fireEvent(boolean isInfoChanged) { |
| if (listeners != null) { |
| for (Listener l : listeners) { |
| if (isInfoChanged) { |
| l.infoChanged(this); |
| } else { |
| l.stateChanged(this); |
| } |
| } |
| } |
| } |
| |
| } |