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 backtype.storm.security.auth;
  
  import java.io.IOException;
  import java.util.Random;
  import org.apache.thrift.transport.TTransport;
  import org.apache.thrift.transport.TTransportException;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  import backtype.storm.utils.StormBoundedExponentialBackoffRetry;
  
  public class TBackoffConnect {
      private static final Logger LOG = LoggerFactory.getLogger(TBackoffConnect.class);
      private int _completedRetries = 0;
      private int _retryTimes;
      private StormBoundedExponentialBackoffRetry waitGrabber;
  
      public TBackoffConnect(int retryTimes, int retryInterval, int retryIntervalCeiling) {
  
          _retryTimes = retryTimes;
          waitGrabber = new StormBoundedExponentialBackoffRetry(retryInterval, retryIntervalCeiling, retryTimes);
      }
  
      public TTransport doConnectWithRetry(ITransportPlugin transportPlugin, TTransport underlyingTransport, String host, String asUser) throws IOException {
          boolean connected = false;
          TTransport transportResult = null;
          while (!connected) {
              try {
                  transportResult = transportPlugin.connect(underlyingTransport, host, asUser);
                  connected = true;
              } catch (TTransportException ex) {
                  retryNext(ex);
              }
          }
          return transportResult;
      }
  
      private void retryNext(TTransportException ex) {
          if (!canRetry()) {
              throw new RuntimeException(ex);
          }
          try {
              int sleeptime = waitGrabber.getSleepTimeMs(_completedRetries, 0);
  
              LOG.debug("Failed to connect. Retrying... (" + Integer.toString(_completedRetries) + ") in " + Integer.toString(sleeptime) + "ms");
  
              Thread.sleep(sleeptime);
          } catch (InterruptedException e) {
              LOG.info("Nimbus connection retry interrupted.");
          }
  
          _completedRetries++;
      }
  
      private boolean canRetry() {
          return (_completedRetries < _retryTimes);
      }
  }
  