1 /*
   2  * Copyright (c) 2018, 2019, 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.Files;
  29 import java.nio.file.Path;
  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.testlibrary.Asserts;
  38 
  39 
  40 /*
  41  * @test
  42  * @summary Reads the recorded file two times and verifies that both reads are the same
  43  * @key jfr
  44  * @library /lib/testlibrary
  45  * @run main/othervm jdk.jfr.api.consumer.TestReadTwice
  46  */
  47 public class TestReadTwice {
  48 
  49     private static class MyEvent extends Event {
  50     }
  51 
  52     public static void main(String[] args) throws Throwable {
  53         Recording r = new Recording();
  54         r.enable(MyEvent.class).withoutStackTrace();
  55         r.start();
  56 
  57         // Commit a single event to the recording
  58         MyEvent event = new MyEvent();
  59         event.commit();
  60 
  61         r.stop();
  62 
  63         // Dump the recording to a file
  64         Path path = Files.createTempFile("recording", ".jfr");
  65         System.out.println("Dumping to " + path);
  66         r.dump(path);
  67         r.close();
  68 
  69         // Read all events from the file in one go
  70         List<RecordedEvent> events = RecordingFile.readAllEvents(path);
  71 
  72         // Read again the same events one by one
  73         RecordingFile rfile = new RecordingFile(path);
  74         List<RecordedEvent> events2 = new LinkedList<>();
  75         while (rfile.hasMoreEvents()) {
  76             events2.add(rfile.readEvent());
  77         }
  78 
  79         // Compare sizes
  80         Asserts.assertEquals(events.size(), events2.size());
  81         rfile.close();
  82     }
  83 }