--- a/src/hotspot/share/jfr/dcmd/jfrDcmds.cpp	Fri Jun 07 21:35:26 2019 -0700
+++ b/src/hotspot/share/jfr/dcmd/jfrDcmds.cpp	Sun Jun 09 11:28:13 2019 +0200
@@ -438,7 +438,13 @@
 
   jobjectArray settings = NULL;
   if (_settings.is_set()) {
-    const int length = _settings.value()->array()->length();
+    int length = _settings.value()->array()->length();
+    if (length == 1) {
+      const char* c_str = _settings.value()->array()->at(0);
+      if (strcmp(c_str, "none") == 0) {
+        length = 0;
+      }
+    }
     settings = JfrJavaSupport::new_string_array(length, CHECK);
     assert(settings != NULL, "invariant");
     for (int i = 0; i < length; ++i) {

--- a/src/hotspot/share/jfr/jni/jfrJavaCall.cpp	Fri Jun 07 21:35:26 2019 -0700
+++ b/src/hotspot/share/jfr/jni/jfrJavaCall.cpp	Sun Jun 09 11:28:13 2019 +0200
@@ -184,7 +184,7 @@
   }
 }
 
-JfrJavaArguments::JfrJavaArguments(JavaValue* result) : _result(result), _klass(NULL), _name(NULL), _signature(NULL), _array_length(0) {
+JfrJavaArguments::JfrJavaArguments(JavaValue* result) : _result(result), _klass(NULL), _name(NULL), _signature(NULL), _array_length(-1) {
   assert(result != NULL, "invariant");
 }
 
@@ -193,7 +193,7 @@
   _klass(NULL),
   _name(NULL),
   _signature(NULL),
-  _array_length(0) {
+  _array_length(-1) {
   assert(result != NULL, "invariant");
   if (klass_name != NULL) {
     set_klass(klass_name, CHECK);
@@ -210,7 +210,7 @@
   _klass(NULL),
   _name(NULL),
   _signature(NULL),
-  _array_length(0) {
+  _array_length(-1) {
   assert(result != NULL, "invariant");
   if (klass != NULL) {
     set_klass(klass);

--- a/src/hotspot/share/jfr/jni/jfrJavaSupport.cpp	Fri Jun 07 21:35:26 2019 -0700
+++ b/src/hotspot/share/jfr/jni/jfrJavaSupport.cpp	Sun Jun 09 11:28:13 2019 +0200
@@ -168,7 +168,7 @@
 
   const int array_length = args->array_length();
 
-  if (array_length > 0) {
+  if (array_length >= 0) {
     array_construction(args, result, klass, array_length, CHECK);
   } else {
     object_construction(args, result, klass, THREAD);

--- a/src/jdk.jfr/share/classes/jdk/jfr/internal/dcmd/DCmdStart.java	Fri Jun 07 21:35:26 2019 -0700
+++ b/src/jdk.jfr/share/classes/jdk/jfr/internal/dcmd/DCmdStart.java	Sun Jun 09 11:28:13 2019 +0200
@@ -24,6 +24,7 @@
  */
 package jdk.jfr.internal.dcmd;
 
+import java.io.FileNotFoundException;
 import java.io.IOException;
 import java.nio.file.Files;
 import java.nio.file.InvalidPathException;
@@ -105,13 +106,17 @@
         if (duration == null && Boolean.FALSE.equals(dumpOnExit) && path != null) {
             throw new DCmdException("Filename can only be set for a time bound recording or if dumponexit=true. Set duration/dumponexit or omit filename.");
         }
-
+        if (settings.length == 1 && settings[0].length() == 0) {
+            throw new DCmdException("No settings specified. Use settings=none to start without any settings");
+        }
         Map<String, String> s = new HashMap<>();
         for (String configName : settings) {
             try {
                 s.putAll(JFC.createKnown(configName).getSettings());
+            } catch(FileNotFoundException e) {
+                throw new DCmdException("Could not find settings file'" + configName + "'", e);
             } catch (IOException | ParseException e) {
-                throw new DCmdException("Could not parse setting " + settings[0], e);
+                throw new DCmdException("Could not parse settings file '" + settings[0] + "'", e);
             }
         }
 

--- a/src/jdk.jfr/share/classes/jdk/jfr/internal/jfc/JFC.java	Fri Jun 07 21:35:26 2019 -0700
+++ b/src/jdk.jfr/share/classes/jdk/jfr/internal/jfc/JFC.java	Sun Jun 09 11:28:13 2019 +0200
@@ -127,7 +127,11 @@
 
     public static String nameFromPath(Path file) throws IOException {
         String f = nullSafeFileName(file);
-        return f.substring(0, f.length() - JFCParser.FILE_EXTENSION.length());
+        if (f.endsWith(JFCParser.FILE_EXTENSION)) {
+            return f.substring(0, f.length() - JFCParser.FILE_EXTENSION.length());
+        } else  {
+            return f;
+        }
     }
 
     // Invoked by DCmdStart

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/jdk/jdk/jfr/startupargs/TestStartNoSettings.java	Sun Jun 09 11:28:13 2019 +0200
@@ -0,0 +1,69 @@
+/*
+ * Copyright (c) 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.startupargs;
+
+import jdk.jfr.Event;
+import jdk.jfr.EventType;
+import jdk.jfr.FlightRecorder;
+import jdk.jfr.Name;
+import jdk.jfr.Recording;
+
+/**
+ * @test
+ * @summary Start a FlightRecording without any settings (not even default).
+ * @key jfr
+ * @requires vm.hasJFR
+ * @library /test/lib
+ * @run main/othervm jdk.jfr.startupargs.TestStartNoSettings
+ *      -XX:StartFlightRecording=settings=none
+ */
+public class TestStartNoSettings {
+
+    @Name("UserEvent")
+    static class UserEvent extends Event {
+    }
+
+    public static void main(String[] a) throws Exception {
+        boolean userEnabled = false;
+        try (Recording r = new Recording()) {
+            r.start();
+            UserEvent e = new UserEvent();
+            e.commit();
+            for (EventType et : FlightRecorder.getFlightRecorder().getEventTypes()) {
+                if (et.isEnabled()) {
+                    if (!et.getName().equals("UserEvent")) {
+                        throw new Exception("Only 'UserEvent' should be enabled");
+                    }
+                    userEnabled = true;
+                }
+            }
+        }
+
+        if (!userEnabled)  {
+            throw new Exception("Expected 'UserEvent' to be enabled with -XX:StartFlightRecording=settings=none");
+        }
+    }
+}