code: /**
   * This file is part of Eclipse Steady.
   *
   * Licensed 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.
   *
   * SPDX-License-Identifier: Apache-2.0
   * SPDX-FileCopyrightText: Copyright (c) 2018-2020 SAP SE or an SAP affiliate company and Eclipse Steady contributors
   */
  package org.eclipse.steady.java.monitor;
  
  import java.util.Observable;
  import java.util.Observer;
  
  import org.apache.logging.log4j.Logger;
  
  /**
   * Calls a sequence methods of a given {@link ExecutionMonitor} in order upload collected
   * information to the Vulas backend. The {@link UploadScheduler} runs either once or periodically,
   * depending on the way it was constructed.
   */
  public class UploadScheduler extends Observable implements Runnable, Observer {
  
    private static final Logger log =
        org.apache.logging.log4j.LogManager.getLogger(UploadScheduler.class);
  
    private long millis = -1;
    private int batchSize = -1;
    private boolean enabled = true;
    private ExecutionMonitor monitor = null;
  
    /**
     * <p>Constructor for UploadScheduler.</p>
     *
     * @param _monitor a {@link org.eclipse.steady.java.monitor.ExecutionMonitor} object.
     */
    public UploadScheduler(ExecutionMonitor _monitor) {
      this(_monitor, -1, -1);
    }
    /**
     * <p>Constructor for UploadScheduler.</p>
     *
     * @param _monitor a {@link org.eclipse.steady.java.monitor.ExecutionMonitor} object.
     * @param _millis a long.
     * @param _batch_size a int.
     */
    public UploadScheduler(ExecutionMonitor _monitor, long _millis, int _batch_size) {
      this.monitor = _monitor;
      this.millis = _millis;
      this.batchSize = _batch_size;
    }
  
    /**
     * <p>enabled.</p>
     */
    public void enabled() {
      this.enabled = true;
    }
    /**
     * <p>disable.</p>
     */
    public void disable() {
      this.enabled = false;
    }
    /**
     * <p>isEnabled.</p>
     *
     * @return a boolean.
     */
    public boolean isEnabled() {
      return this.enabled;
    }
    /**
     * <p>getInterval.</p>
     *
     * @return a long.
     */
    public long getInterval() {
      return this.millis;
    }
    /**
     * <p>Getter for the field <code>batchSize</code>.</p>
     *
     * @return a int.
     */
    public int getBatchSize() {
      return this.batchSize;
    }
  
    /**
     * Calls a sequence of methods of a {@link ExecutionMonitor}.
     */
    public void run() {
      // Final upload
      if (this.millis == -1) {
  
        // Stop further instrumentation and collection (that may happen in the course of the following
        // stmts)
        this.monitor.setPaused(true);
        DynamicTransformer.getInstance().setTransformationEnabled(false);
  
        // Upload stuff
        this.monitor.uploadInformation();
        this.monitor.awaitUpload();
        this.monitor.stopGoal();
  
        // Log instrumentation stats
        InstrumentationControl.logOverallStatistics();
  
        // Notify others that the final upload took place
        this.notifyObservers();
      }
      // Periodic uploads
      else {
        while (this.isEnabled()) {
          try {
            Thread.sleep(this.millis);
            if (this.isEnabled()) {
              this.monitor.uploadInformation(this.batchSize);
  
              // Log instrumentation stats
              InstrumentationControl.logOverallStatistics();
            }
          } catch (InterruptedException e) {
            UploadScheduler.log.error("Error in periodic trace upload: " + e.getMessage());
          }
        }
      }
    }
  
    /**
     * {@inheritDoc}
     *
     * Disables periodic uploads (called by the shutdown uploader).
     */
    public void update(Observable obj, Object arg) {
      this.disable();
      UploadScheduler.log.info("Uploader disabled");
    }
  }
  