--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/jdk/jdk/jfr/event/io/IOHelper.java	Tue May 15 20:24:34 2018 +0200
@@ -0,0 +1,129 @@
+/*
+ * Copyright (c) 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.jfr.event.io;
+
+import static jdk.test.lib.Asserts.assertEquals;
+import static jdk.test.lib.Asserts.assertTrue;
+
+import java.util.List;
+import java.util.stream.Collectors;
+
+import jdk.jfr.event.io.IOEvent.EventType;
+
+import jdk.jfr.consumer.RecordedEvent;
+import jdk.test.lib.jfr.Events;
+
+
+// Helper class to match actual RecordedEvents to expected events.
+public class IOHelper {
+
+    public static void verifyEqualsInOrder(List<RecordedEvent> events, List<IOEvent> expectedEvents) throws Throwable {
+        List<IOEvent> actualEvents = getTestEvents(events, expectedEvents);
+        try {
+            assertEquals(actualEvents.size(), expectedEvents.size(), "Wrong number of events.");
+            for (int i = 0; i < actualEvents.size(); ++i) {
+                assertEquals(actualEvents.get(i), expectedEvents.get(i), "Wrong event at pos " + i);
+            }
+        } catch (Throwable t) {
+            logEvents(actualEvents, expectedEvents);
+            throw t;
+        }
+    }
+
+
+    public static void verifyEquals(List<RecordedEvent> events, List<IOEvent> expectedEvents) throws Throwable {
+        List<IOEvent> actualEvents = getTestEvents(events, expectedEvents);
+        try {
+            assertEquals(actualEvents.size(), expectedEvents.size(), "Wrong number of events");
+            assertTrue(actualEvents.containsAll(expectedEvents), "Not all expected events received");
+            assertTrue(expectedEvents.containsAll(actualEvents), "Received unexpected events");
+        } catch (Throwable t) {
+            logEvents(actualEvents, expectedEvents);
+            throw t;
+        }
+    }
+
+
+    private static List<IOEvent> getTestEvents(List<RecordedEvent> events, List<IOEvent> expectedEvents) throws Throwable {
+        // Log all events
+        for (RecordedEvent event : events) {
+            String msg = event.getEventType().getName();
+            boolean isSocket = IOEvent.EVENT_SOCKET_READ.equals(msg) || IOEvent.EVENT_SOCKET_WRITE.equals(msg);
+            boolean isFile = IOEvent.EVENT_FILE_FORCE.equals(msg) || IOEvent.EVENT_FILE_READ.equals(msg) || IOEvent.EVENT_FILE_WRITE.equals(msg);
+            boolean isFileReadOrWrite = IOEvent.EVENT_FILE_READ.equals(msg) || IOEvent.EVENT_FILE_WRITE.equals(msg);
+            boolean isRead = IOEvent.EVENT_FILE_READ.equals(msg) || IOEvent.EVENT_SOCKET_READ.equals(msg);
+            if (isFile) {
+                msg += " : " + Events.assertField(event, "path").getValue();
+            } else if (isSocket) {
+                msg += " - " + Events.assertField(event, "host").getValue();
+                msg += "." + Events.assertField(event, "address").getValue();
+                msg += "." + Events.assertField(event, "port").getValue();
+            }
+            if (isSocket || isFileReadOrWrite) {
+                String field = isRead ? "bytesRead" : "bytesWritten";
+                msg += " : " + Events.assertField(event, field).getValue();
+            }
+            System.out.println(msg);
+        }
+
+        return events.stream()
+                        .filter(event -> isTestEvent(event, expectedEvents))
+                        .map(event -> IOEvent.createTestEvent(event))
+                        .collect(Collectors.toList());
+    }
+
+    // A recording may contain extra events that are not part of the test.
+    // This function filters out events that not belong to the test.
+    public static boolean isTestEvent(RecordedEvent event, List<IOEvent> testEvents) {
+        EventType eventType = IOEvent.getEventType(event);
+        if (eventType == EventType.UnknownEvent) {
+                return false;
+        }
+
+        // Only care about threads in the expected threads.
+        final String threadName = event.getThread().getJavaName();
+        if (testEvents.stream().noneMatch(te -> te.thread.equals(threadName))) {
+                return false;
+        }
+
+        // Only care about files and sockets in expected events.
+        final String address = IOEvent.getEventAddress(event);
+        if (testEvents.stream().noneMatch(te -> te.address.equals(address))) {
+                return false;
+        }
+        return true;
+    }
+
+    private static void logEvents(List<IOEvent> actualEvents, List<IOEvent> expectedEvents) {
+        for (int i = 0; i < actualEvents.size(); ++i) {
+            System.out.println("actual event[" + i + "] = " + actualEvents.get(i));
+        }
+        for (int i = 0; i < expectedEvents.size(); ++i) {
+            System.out.println("expected event[" + i + "] = " + expectedEvents.get(i));
+        }
+    }
+
+}