content: /**
   * 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.activemq.transport.ws;
  
  import java.io.IOException;
  import java.time.Duration;
  import java.util.concurrent.BlockingQueue;
  import java.util.concurrent.CountDownLatch;
  import java.util.concurrent.LinkedBlockingDeque;
  import java.util.concurrent.TimeUnit;
  
  import org.apache.activemq.transport.stomp.StompFrame;
  import org.apache.activemq.transport.stomp.StompWireFormat;
  import org.eclipse.jetty.websocket.api.Session;
  import org.eclipse.jetty.websocket.api.WebSocketAdapter;
  import org.eclipse.jetty.websocket.api.WebSocketListener;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  /**
   * STOMP over WS based Connection class
   */
  public class StompWSConnection extends WebSocketAdapter implements WebSocketListener {
  
      private static final Logger LOG = LoggerFactory.getLogger(StompWSConnection.class);
  
      private Session connection;
      private final CountDownLatch connectLatch = new CountDownLatch(1);
  
      private final BlockingQueue<String> prefetch = new LinkedBlockingDeque<String>();
      private final StompWireFormat wireFormat = new StompWireFormat();
  
      private int closeCode = -1;
      private String closeMessage;
  
      @Override
      public boolean isConnected() {
          return connection != null ? connection.isOpen() : false;
      }
  
      public void close() {
          if (connection != null) {
              connection.close();
          }
      }
  
      protected Session getConnection() {
          return connection;
      }
  
      //---- Send methods ------------------------------------------------------//
  
      public synchronized void sendRawFrame(String rawFrame) throws Exception {
          checkConnected();
          connection.getRemote().sendString(rawFrame);
      }
  
      public synchronized void sendFrame(StompFrame frame) throws Exception {
          checkConnected();
          connection.getRemote().sendString(wireFormat.marshalToString(frame));
      }
  
      public synchronized void keepAlive() throws Exception {
          checkConnected();
          connection.getRemote().sendString("\n");
      }
  
      //----- Receive methods --------------------------------------------------//
  
      public String receive() throws Exception {
          checkConnected();
          return prefetch.take();
      }
  
      public String receive(long timeout, TimeUnit unit) throws Exception {
          checkConnected();
          return prefetch.poll(timeout, unit);
      }
  
      public String receiveNoWait() throws Exception {
          checkConnected();
          return prefetch.poll();
      }
  
      //---- Blocking state change calls ---------------------------------------//
  
      public void awaitConnection() throws InterruptedException {
          connectLatch.await();
      }
  
      public boolean awaitConnection(long time, TimeUnit unit) throws InterruptedException {
          return connectLatch.await(time, unit);
      }
  
      //----- Property Accessors -----------------------------------------------//
  
      public int getCloseCode() {
          return closeCode;
      }
  
      public String getCloseMessage() {
          return closeMessage;
      }
  
      //----- WebSocket callback handlers --------------------------------------//
  
      @Override
      public void onWebSocketText(String data) {
          if (data == null) {
              return;
          }
  
          if (data.equals("\n")) {
              LOG.debug("New incoming heartbeat read");
          } else {
              LOG.trace("New incoming STOMP Frame read: \n{}", data);
              prefetch.add(data);
          }
      }
  
      @Override
      public void onWebSocketClose(int statusCode, String reason) {
          LOG.trace("STOMP WS Connection closed, code:{} message:{}", statusCode, reason);
  
          this.connection = null;
          this.closeCode = statusCode;
          this.closeMessage = reason;
      }
  
      @Override
      public void onWebSocketConnect(org.eclipse.jetty.websocket.api.Session session) {
          this.connection = session;
          this.connection.setIdleTimeout(Duration.ZERO);
          this.connectLatch.countDown();
      }
  
      //----- Internal implementation ------------------------------------------//
  
      private void checkConnected() throws IOException {
          if (!isConnected()) {
              throw new IOException("STOMP WS Connection is closed.");
          }
      }
  }
  