1 /*
   2  * Copyright (c) 2016, 2018, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package jdk.management.jfr;
  27 
  28 import java.io.IOException;
  29 import java.io.InputStream;
  30 import java.util.Date;
  31 import java.util.HashMap;
  32 import java.util.Map;
  33 import java.util.Timer;
  34 import java.util.concurrent.TimeUnit;
  35 
  36 final class StreamManager {
  37 
  38     public static final long TIME_OUT = TimeUnit.MINUTES.toMillis(2);
  39     public static final int DEFAULT_BLOCK_SIZE = 50000;
  40 
  41     private static long idCounter = 0;
  42 
  43     private final Map<Long, Stream> streams = new HashMap<>();
  44     private Timer timer;
  45 
  46     public synchronized Stream getStream(long streamIdentifer) {
  47         Stream stream = streams.get(streamIdentifer);
  48         if (stream == null) {
  49             throw new IllegalArgumentException("Unknown stream identifier " + streamIdentifer);
  50         }
  51         return stream;
  52     }
  53 
  54     public synchronized Stream create(InputStream is, int blockSize) {
  55         idCounter++;
  56         Stream stream = new Stream(is, idCounter, blockSize);
  57         streams.put(stream.getId(), stream);
  58 
  59         scheduleAbort(stream, System.currentTimeMillis() + TIME_OUT);
  60         return stream;
  61     }
  62 
  63     public synchronized void destroy(Stream stream) {
  64         try {
  65             stream.close();
  66         } catch (IOException e) {
  67             // OK
  68         }
  69         streams.remove(stream.getId());
  70         if (streams.isEmpty()) {
  71             timer.cancel();
  72             timer = null;
  73         }
  74     }
  75 
  76     public synchronized void scheduleAbort(Stream s, long when) {
  77         if (timer == null) {
  78             timer = new Timer(true);
  79         }
  80         timer.schedule(new StreamCleanupTask(this, s), new Date(when + TIME_OUT));
  81     }
  82 }