--- /dev/null	2017-11-09 09:38:01.297999907 +0100
+++ new/src/jdk.management.jfr/share/classes/jdk/management/jfr/StreamManager.java	2018-04-09 16:27:44.472958820 +0200
@@ -0,0 +1,82 @@
+/*
+ * Copyright (c) 2016, 2018, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+package jdk.management.jfr;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.Date;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Timer;
+import java.util.concurrent.TimeUnit;
+
+final class StreamManager {
+
+    public static final long TIME_OUT = TimeUnit.MINUTES.toMillis(2);
+    public static final int DEFAULT_BLOCK_SIZE = 50000;
+
+    private static long idCounter = 0;
+
+    private final Map<Long, Stream> streams = new HashMap<>();
+    private Timer timer;
+
+    public synchronized Stream getStream(long streamIdentifer) {
+        Stream stream = streams.get(streamIdentifer);
+        if (stream == null) {
+            throw new IllegalArgumentException("Unknown stream identifier " + streamIdentifer);
+        }
+        return stream;
+    }
+
+    public synchronized Stream create(InputStream is, int blockSize) {
+        idCounter++;
+        Stream stream = new Stream(is, idCounter, blockSize);
+        streams.put(stream.getId(), stream);
+
+        scheduleAbort(stream, System.currentTimeMillis() + TIME_OUT);
+        return stream;
+    }
+
+    public synchronized void destroy(Stream stream) {
+        try {
+            stream.close();
+        } catch (IOException e) {
+            // OK
+        }
+        streams.remove(stream.getId());
+        if (streams.isEmpty()) {
+            timer.cancel();
+            timer = null;
+        }
+    }
+
+    public synchronized void scheduleAbort(Stream s, long when) {
+        if (timer == null) {
+            timer = new Timer(true);
+        }
+        timer.schedule(new StreamCleanupTask(this, s), new Date(when + TIME_OUT));
+    }
+}