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.artemis.utils.critical;
  
  import java.util.concurrent.atomic.AtomicIntegerFieldUpdater;
  
  import org.apache.activemq.artemis.utils.ArtemisCloseable;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  import java.lang.invoke.MethodHandles;
  
  public class CriticalMeasure {
  
     public static boolean isDummy(ArtemisCloseable closeable) {
        return closeable == dummyCloseable;
     }
  
     private static final Logger logger = LoggerFactory.getLogger(MethodHandles.lookup().lookupClass());
  
     // this is used on enterCritical, if the logger is in trace mode
     private volatile Exception traceEnter;
     static final AtomicIntegerFieldUpdater<CriticalMeasure> CURRENT_MEASURING = AtomicIntegerFieldUpdater.newUpdater(CriticalMeasure.class, "measuring");
  
     private final CriticalCloseable autoCloseable = new CriticalCloseable() {
        ArtemisCloseable beforeClose;
  
        @Override
        public void beforeClose(ArtemisCloseable closeable) {
           beforeClose = closeable;
        }
  
        @Override
        public void close() {
           try {
              if (beforeClose != null) {
                 beforeClose.close();
                 beforeClose = null;
              }
           } finally {
              leaveCritical();
              CURRENT_MEASURING.set(CriticalMeasure.this, 0);
           }
        }
     };
  
     protected static final CriticalCloseable dummyCloseable = new CriticalCloseable() {
        @Override
        public void beforeClose(ArtemisCloseable runnable) {
           throw new IllegalStateException("The dummy closeable does not support beforeClose. Check before CriticalMeasure.isDummy(closeable) before you call beforeClose(runnable)");
        }
  
        @Override
        public void close() {
        }
     };
  
     // this is working like a boolean, although using AtomicIntegerFieldUpdater instead
     protected volatile int measuring;
     protected volatile long timeEnter;
  
     private final int id;
     private final CriticalComponent component;
  
     public CriticalMeasure(CriticalComponent component, int id) {
        this.id = id;
        this.component = component;
        this.timeEnter = 0;
     }
  
     public CriticalCloseable measure() {
        // I could have chosen to simply store the time on this value, however I would be calling nanoTime a lot of times
        // to just waste the value
        // So, I keep a measuring atomic to protect the thread sampling,
        // and I will still do the set using a single thread.
        if (CURRENT_MEASURING.compareAndSet(this, 0, 1)) {
           enterCritical();
           return autoCloseable;
        } else {
           return dummyCloseable;
        }
     }
  
     protected void enterCritical() {
        timeEnter = System.nanoTime();
  
        if (logger.isTraceEnabled()) {
           traceEnter = new Exception("entered");
        }
     }
  
     protected void leaveCritical() {
        if (logger.isTraceEnabled()) {
  
           CriticalAnalyzer analyzer = component != null ? component.getCriticalAnalyzer() : null;
           if (analyzer != null) {
              long nanoTimeout = analyzer.getTimeoutNanoSeconds();
              if (checkExpiration(nanoTimeout, false)) {
                 logger.trace("Path {} on component {} is taking too long, leaving at {}", id, getComponentName(), new Exception("left"));
                 logger.trace("Path {} on component {} is taking too long, entered at", id, getComponentName(), traceEnter);
              }
           }
           traceEnter = null;
        }
        timeEnter = 0L;
     }
  
     protected String getComponentName() {
        if (component == null) {
           return "null";
        } else {
           return component.getClass().getName();
        }
     }
  
     public boolean checkExpiration(long timeout, boolean reset) {
        final long thisTimeEnter = this.timeEnter;
        if (thisTimeEnter != 0L) {
           long time = System.nanoTime();
           boolean expired = time - thisTimeEnter > timeout;
  
           if (expired) {
              Exception lastTraceEnter = this.traceEnter;
  
              if (lastTraceEnter != null) {
                 logger.warn("Component {} is expired on path {}", getComponentName(), id, lastTraceEnter);
              } else {
                 logger.warn("Component {} is expired on path {}", getComponentName(), id);
              }
  
              if (reset) {
                 this.timeEnter = 0;
              }
  
           }
           return expired;
        }
        return false;
     }
  }
  