MessagePool.java

/*
 * Copyright 2000-2017 JetBrains s.r.o.
 *
 * 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.
 */
package com.intellij.diagnostic;

import com.intellij.openapi.diagnostic.IdeaLoggingEvent;
import com.intellij.util.concurrency.AppExecutorUtil;
import com.intellij.util.containers.ContainerUtil;
import org.apache.log4j.Category;
import org.apache.log4j.Priority;
import org.apache.log4j.spi.LoggingEvent;
import org.jetbrains.annotations.NotNull;
import org.jetbrains.annotations.Nullable;

import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.CompletableFuture;
import java.util.concurrent.Future;
import java.util.concurrent.TimeUnit;

public class MessagePool {
  private static final int MAX_POOL_SIZE_FOR_FATALS = 100;

  private final List<AbstractMessage> myIdeFatals = ContainerUtil.createLockFreeCopyOnWriteList();

  private final List<MessagePoolListener> myListeners = ContainerUtil.createLockFreeCopyOnWriteList();

  private final MessageGrouper myFatalsGrouper;

  MessagePool(int maxGroupSize, int timeout) {
    myFatalsGrouper = new MessageGrouper(timeout, maxGroupSize);
  }

  private static class MessagePoolHolder {
    private static final MessagePool ourInstance = new MessagePool(20, 1000);
  }

  public static MessagePool getInstance() {
    return MessagePoolHolder.ourInstance;
  }

  @Nullable
  public LogMessage addIdeFatalMessage(final IdeaLoggingEvent aEvent) {
    Object data = aEvent.getData();
    final LogMessage message = data instanceof LogMessage ? (LogMessage)data : new LogMessage(aEvent);
    if (myIdeFatals.size() < MAX_POOL_SIZE_FOR_FATALS) {
      if (myFatalsGrouper.addToGroup(message)) {
        return message;
      }
    } else if (myIdeFatals.size() == MAX_POOL_SIZE_FOR_FATALS) {
      String msg = DiagnosticBundle.message("error.monitor.too.many.errors");
      LogMessage tooMany = new LogMessage(new LoggingEvent(msg, Category.getRoot(), Priority.ERROR, null, new TooManyErrorsException()));
      myFatalsGrouper.addToGroup(tooMany);
      return tooMany;
    }
    return null;
  }

  public List<AbstractMessage> getFatalErrors(boolean aIncludeReadMessages, boolean aIncludeSubmittedMessages) {
    List<AbstractMessage> result = new ArrayList<>();
    for (AbstractMessage each : myIdeFatals) {
      if (!each.isRead() && !each.isSubmitted()) {
        result.add(each);
      }
      else if ((each.isRead() && aIncludeReadMessages) || (each.isSubmitted() && aIncludeSubmittedMessages)) {
        result.add(each);
      }
    }
    return result;
  }

  public void clearFatals() {
    for (AbstractMessage fatal : myIdeFatals) {
      fatal.setRead(true); // expire notifications
    }

    myIdeFatals.clear();
    notifyListenersClear();
  }

  public void addListener(MessagePoolListener aListener) {
    myListeners.add(aListener);
  }

  public void removeListener(MessagePoolListener aListener) {
    myListeners.remove(aListener);
  }

  private void notifyListenersAdd() {
    for (MessagePoolListener messagePoolListener : myListeners) {
      messagePoolListener.newEntryAdded();
    }
  }

  private void notifyListenersClear() {
    for (MessagePoolListener messagePoolListener : myListeners) {
      messagePoolListener.poolCleared();
    }
  }

  void notifyListenersRead() {
    for (MessagePoolListener messagePoolListener : myListeners) {
      messagePoolListener.entryWasRead();
    }
  }

  private class MessageGrouper implements Runnable {
    private final int myTimeOut;
    private final int myMaxGroupSize;
    private final List<AbstractMessage> myMessages = new ArrayList<>();
    private Future<?> myAlarm = CompletableFuture.completedFuture(null);

    public MessageGrouper(int timeout, int maxGroupSize) {
      myTimeOut = timeout;
      myMaxGroupSize = maxGroupSize;
    }

    public void run() {
      synchronized (myMessages) {
        if (myMessages.size() > 0) {
          post();
        }
      }
    }

    private void post() {
      AbstractMessage message;
      if (myMessages.size() == 1) {
        message = myMessages.get(0);
      } else {
        message = new GroupedLogMessage(new ArrayList<>(myMessages));
      }
      message.setOnReadCallback(() -> notifyListenersRead());
      myMessages.clear();
      myIdeFatals.add(message);
      notifyListenersAdd();
    }

    public boolean addToGroup(@NotNull AbstractMessage message) {
      boolean result = myMessages.isEmpty();
      synchronized(myMessages) {
        myMessages.add(message);
        if (myMessages.size() >= myMaxGroupSize) {
          post();
        } else {
          myAlarm.cancel(false);
          myAlarm = AppExecutorUtil.getAppScheduledExecutorService().schedule(this, myTimeOut, TimeUnit.MILLISECONDS);
        }
      }
      return result;
    }
  }

  public static class TooManyErrorsException extends Exception {
    TooManyErrorsException() {
      super(DiagnosticBundle.message("error.monitor.too.many.errors"));
    }
  }
}