| /* |
| * 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.reef.util.logging; |
| |
| import org.apache.reef.javabridge.NativeInterop; |
| |
| import javax.inject.Inject; |
| import java.util.ArrayList; |
| import java.util.concurrent.ScheduledThreadPoolExecutor; |
| import java.util.concurrent.TimeUnit; |
| import java.util.logging.Handler; |
| import java.util.logging.Level; |
| import java.util.logging.LogRecord; |
| import java.util.logging.SimpleFormatter; |
| |
| /** |
| * Logging Handler to intercept java logs and transfer them |
| * to the CLR side via the reef-bridge. |
| * <p> |
| * Logs are buffered to avoid the cost of reef-bridge function calls. |
| * A thread is also scheduled to flush the log buffer at a certain interval, |
| * in case the log buffer remains unfilled for an extended period of time. |
| */ |
| public class CLRBufferedLogHandler extends Handler { |
| private static final int BUFFER_LEN = 10; |
| private static final int NUM_THREADS = 1; |
| private static final long LOG_SCHEDULE_PERIOD = 15; // seconds |
| private SimpleFormatter formatter; |
| private ArrayList<LogRecord> logs; |
| private boolean driverInitialized; |
| private ScheduledThreadPoolExecutor logScheduler; |
| |
| @Inject |
| public CLRBufferedLogHandler() { |
| super(); |
| this.formatter = new SimpleFormatter(); |
| this.logs = new ArrayList<>(); |
| this.driverInitialized = false; |
| this.logScheduler = new ScheduledThreadPoolExecutor(NUM_THREADS); |
| } |
| |
| /** |
| * Signals the java-bridge has been initialized and that we can begin logging. |
| * Usually called from the StartHandler after the driver is up. |
| */ |
| public void setDriverInitialized() { |
| synchronized (this) { |
| this.driverInitialized = true; |
| } |
| startLogScheduler(); |
| } |
| |
| /** |
| * Called whenever a log message is received on the java side. |
| * <p> |
| * Adds the log record to the log buffer. If the log buffer is full and |
| * the driver has already been initialized, flush the buffer of the logs. |
| */ |
| @Override |
| public void publish(final LogRecord record) { |
| if (record == null) { |
| return; |
| } |
| |
| if (!isLoggable(record)) { |
| return; |
| } |
| |
| synchronized (this) { |
| this.logs.add(record); |
| if (!this.driverInitialized || this.logs.size() < BUFFER_LEN) { |
| return; |
| } |
| } |
| |
| logAll(); |
| } |
| |
| @Override |
| public void flush() { |
| logAll(); |
| } |
| |
| /** |
| * Flushes the remaining buffered logs and shuts down the log scheduler thread. |
| */ |
| @Override |
| public synchronized void close() throws SecurityException { |
| if (driverInitialized) { |
| this.logAll(); |
| } |
| this.logScheduler.shutdown(); |
| } |
| |
| /** |
| * Starts a thread to flush the log buffer on an interval. |
| * <p> |
| * This will ensure that logs get flushed periodically, even |
| * if the log buffer is not full. |
| */ |
| private void startLogScheduler() { |
| this.logScheduler.scheduleAtFixedRate( |
| new Runnable() { |
| @Override |
| public void run() { |
| CLRBufferedLogHandler.this.logAll(); |
| } |
| }, 0, LOG_SCHEDULE_PERIOD, TimeUnit.SECONDS); |
| } |
| |
| /** |
| * Flushes the log buffer, logging each buffered log message using |
| * the reef-bridge log function. |
| */ |
| private void logAll() { |
| synchronized (this) { |
| final StringBuilder sb = new StringBuilder(); |
| Level highestLevel = Level.FINEST; |
| for (final LogRecord record : this.logs) { |
| sb.append(formatter.format(record)); |
| sb.append("\n"); |
| if (record.getLevel().intValue() > highestLevel.intValue()) { |
| highestLevel = record.getLevel(); |
| } |
| } |
| try { |
| final int level = getLevel(highestLevel); |
| NativeInterop.clrBufferedLog(level, sb.toString()); |
| } catch (Exception e) { |
| System.err.println("Failed to perform CLRBufferedLogHandler"); |
| } |
| |
| this.logs.clear(); |
| } |
| } |
| |
| /** |
| * Returns the integer value of the log record's level to be used |
| * by the CLR Bridge log function. |
| */ |
| private int getLevel(final Level recordLevel) { |
| if (recordLevel.equals(Level.OFF)) { |
| return 0; |
| } else if (recordLevel.equals(Level.SEVERE)) { |
| return 1; |
| } else if (recordLevel.equals(Level.WARNING)) { |
| return 2; |
| } else if (recordLevel.equals(Level.ALL)) { |
| return 4; |
| } else { |
| return 3; |
| } |
| } |
| } |