content: package act.monitor;
  
  /*-
   * #%L
   * ACT Framework
   * %%
   * Copyright (C) 2014 - 2018 ActFramework
   * %%
   * 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.
   * #L%
   */
  
  import java.lang.management.*;
  import java.util.HashMap;
  import java.util.Map;
  import javax.inject.Singleton;
  
  /**
   * A `Probe` is a worker that probe system and return data
   */
  public interface Probe {
      /**
       * The identifier of this probe. This could be used
       * for consumer to subscribe the data collected by
       * the probe
       *
       * @return the probe id.
       */
      String id();
      /**
       * Do probe job once and return the data
       *
       * @return the data
       */
      Map<String, Object> doJob();
  
      @Singleton
      class SystemProbe implements Probe {
  
          private RuntimeMXBean runtimeMXBean;
          private ThreadMXBean threadMXBean;
          private MemoryMXBean memoryMXBean;
  
          private Map<String, Object> status = new HashMap<>();
  
          public SystemProbe() {
              runtimeMXBean = ManagementFactory.getRuntimeMXBean();
              threadMXBean = ManagementFactory.getThreadMXBean();
              memoryMXBean = ManagementFactory.getMemoryMXBean();
          }
  
          @Override
          public String id() {
              return "sys";
          }
  
          @Override
          public Map<String, Object> doJob() {
              status.put("memory", memoryMXBean.getHeapMemoryUsage());
              status.put("threads", threadMXBean.getThreadCount());
              status.put("start", runtimeMXBean.getStartTime());
              status.put("uptime", runtimeMXBean.getUptime());
              return status;
          }
      }
  }
  