--- /dev/null	2018-06-17 23:18:20.806999507 +0800
+++ new/src/share/classes/jdk/jfr/internal/management/ManagementSupport.java	2019-01-29 11:00:16.895465113 +0800
@@ -0,0 +1,93 @@
+/*
+ * Copyright (c) 2016, 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.internal.management;
+
+import java.time.Duration;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+
+import jdk.jfr.EventType;
+import jdk.jfr.internal.JVMSupport;
+import jdk.jfr.internal.LogLevel;
+import jdk.jfr.internal.LogTag;
+import jdk.jfr.internal.Logger;
+import jdk.jfr.internal.MetadataRepository;
+import jdk.jfr.internal.Utils;
+import jdk.jfr.internal.instrument.JDKEvents;
+
+/**
+ * The management API in module jdk.management.jfr should be built on top of the
+ * public API in jdk.jfr. Before putting more functionality here, consider if it
+ * should not be part of the public API, and if not, please provide motivation
+ *
+ */
+public final class ManagementSupport {
+
+    // Purpose of this method is to expose the event types to the
+    // FlightRecorderMXBean without instantiating Flight Recorder.
+    //
+    // This allows:
+    //
+    // 1) openJDK tests to run without commercial features being
+    // unlocked, which would be the case if FlightRecorder#getEventTypes would
+    // be used.
+    //
+    // 2 discoverability, so event settings can be exposed without the need to
+    // create a new Recording in FlightrecorderMXBean.
+    //
+    // 3) a graphical JMX client to list all attributes to the user, without
+    // loading JFR memory buffers. This is especially important when there is
+    // no intent to use Flight Recorder.
+    //
+    // An alternative design would be to make FlightRecorder#getEventTypes
+    // static, but it would the make the API look strange
+    //
+    public static List<EventType> getEventTypes() {
+        // would normally be checked when a Flight Recorder instance is created
+        Utils.checkAccessFlightRecorder();
+        if (JVMSupport.isNotAvailable()) {
+            return new ArrayList<>();
+        }
+        JDKEvents.initialize(); // make sure JDK events are available
+        return Collections.unmodifiableList(MetadataRepository.getInstance().getRegisteredEventTypes());
+    }
+
+    // Reuse internal code for parsing a timespan
+    public static long parseTimespan(String s) {
+        return Utils.parseTimespan(s);
+    }
+
+    // Reuse internal code for formatting settings
+    public static final String formatTimespan(Duration dValue, String separation) {
+        return Utils.formatTimespan(dValue, separation);
+    }
+
+    // Reuse internal logging mechanism
+    public static void logError(String message) {
+        Logger.log(LogTag.JFR, LogLevel.ERROR, message);
+    }
+}