1 /*
   2  * Copyright (c) 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.jfr.api.consumer;
  27 
  28 import java.nio.file.Path;
  29 import java.nio.file.Paths;
  30 import java.util.LinkedList;
  31 import java.util.List;
  32 
  33 import jdk.jfr.Event;
  34 import jdk.jfr.Recording;
  35 import jdk.jfr.consumer.RecordedEvent;
  36 import jdk.jfr.consumer.RecordingFile;
  37 import jdk.test.lib.Asserts;
  38 import jdk.test.lib.Utils;
  39 
  40 
  41 /**
  42  * @test
  43  * @summary Reads the recorded file two times and verifies that both reads are the same
  44  * @key jfr
  45  *
  46  * @library /lib /
  47  * @run main/othervm jdk.jfr.api.consumer.TestReadTwice
  48  */
  49 public class TestReadTwice {
  50 
  51     private static class MyEvent extends Event {
  52     }
  53 
  54     public static void main(String[] args) throws Throwable {
  55         Recording r = new Recording();
  56         r.enable(MyEvent.class).withoutStackTrace();
  57         r.start();
  58 
  59         // Commit a single event to the recording
  60         MyEvent event = new MyEvent();
  61         event.commit();
  62 
  63         r.stop();
  64 
  65         // Dump the recording to a file
  66         Path path = Utils.createTempFile("read-twice", ".jfr");
  67         System.out.println("Dumping to " + path);
  68         r.dump(path);
  69         r.close();
  70 
  71         // Read all events from the file in one go
  72         List<RecordedEvent> events = RecordingFile.readAllEvents(path);
  73 
  74         // Read again the same events one by one
  75         RecordingFile rfile = new RecordingFile(path);
  76         List<RecordedEvent> events2 = new LinkedList<>();
  77         while (rfile.hasMoreEvents()) {
  78             events2.add(rfile.readEvent());
  79         }
  80 
  81         // Compare sizes
  82         Asserts.assertEquals(events.size(), events2.size());
  83         rfile.close();
  84     }
  85 }