--- /dev/null	2018-06-17 23:18:20.806999507 +0800
+++ new/test/jdk/jfr/api/recording/event/TestLoadEventAfterStart.java	2019-01-29 11:02:04.340340743 +0800
@@ -0,0 +1,89 @@
+/*
+ * Copyright (c) 2018, 2019, 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.api.recording.event;
+
+import java.lang.reflect.Constructor;
+import java.time.Duration;
+import java.util.ArrayList;
+import java.util.List;
+
+import jdk.jfr.Event;
+import jdk.jfr.Recording;
+import jdk.jfr.consumer.RecordedEvent;
+import jdk.testlibrary.Asserts;
+import jdk.testlibrary.jfr.Events;
+
+/*
+ * @test
+ * @summary Load event class after recording started.
+ * @key jfr
+ * @library /lib/testlibrary
+ * @build jdk.testlibrary.jfr.SimpleEvent
+ * @run main/othervm jdk.jfr.api.recording.event.TestLoadEventAfterStart
+ */
+public class TestLoadEventAfterStart {
+
+    public static void main(String[] args) throws Throwable {
+        Recording r = new Recording();
+        r.start();
+
+        ClassLoader classLoader = TestLoadEventAfterStart.class.getClassLoader();
+        Class<? extends Event> eventClass =
+            classLoader.loadClass("jdk.testlibrary.jfr.SimpleEvent").asSubclass(Event.class);
+
+        r.enable(eventClass).withThreshold(Duration.ofMillis(0)).withoutStackTrace();
+        createEvent(eventClass, 1);
+        r.disable(eventClass);
+        createEvent(eventClass, 2);
+        r.enable(eventClass).withThreshold(Duration.ofMillis(0)).withoutStackTrace();
+        createEvent(eventClass, 3);
+
+        r.stop();
+        verifyEvents(r, 1, 3);
+    }
+
+    private static void verifyEvents(Recording r, int ... ids) throws Exception {
+        List<Integer> eventIds = new ArrayList<>();
+        for (RecordedEvent event : Events.fromRecording(r)) {
+            int id = Events.assertField(event, "id").getValue();
+            System.out.println("Event id:" + id);
+            eventIds.add(id);
+        }
+        Asserts.assertEquals(eventIds.size(), ids.length, "Wrong number of events");
+        for (int i = 0; i < ids.length; ++i) {
+            Asserts.assertEquals(eventIds.get(i).intValue(), ids[i], "Wrong id in event");
+        }
+    }
+
+    private static void createEvent(Class<? extends Event> eventClass, int id) throws Exception {
+        Constructor<? extends Event> constructor = eventClass.getConstructor();
+        Event event = (Event) constructor.newInstance();
+        event.begin();
+        eventClass.getDeclaredField("id").setInt(event, id);
+        event.end();
+        event.commit();
+    }
+}