--- /dev/null	2017-11-09 09:38:01.297999907 +0100
+++ new/src/jdk.jfr/share/classes/jdk/jfr/internal/cmd/Command.java	2018-04-09 16:07:13.001352160 +0200
@@ -0,0 +1,150 @@
+/*
+ * Copyright (c) 2016, 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.internal.cmd;
+
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.Deque;
+import java.util.List;
+
+abstract class Command {
+
+    private final static Command HELP = new HelpCommand();
+    private final static List<Command> COMMANDS = createCommands();
+
+    static void displayHelp() {
+        System.out.println("Usage: java " + Execute.class.getName() + " <command> [<options>]");
+        System.out.println();
+        displayAvailableCommands();
+    }
+
+    static void displayAvailableCommands() {
+        System.out.println("Available commands are:");
+        System.out.println();
+        boolean first = true;
+        for (Command c : Command.COMMANDS) {
+            if (!first) {
+                System.out.println();
+            }
+            System.out.println("  " + c.getName() + " " + c.getOptionSyntax());
+            System.out.println("    " + c.getDescription());
+            first = false;
+        }
+    }
+
+    public static List<Command> getCommands() {
+        return COMMANDS;
+    }
+
+    public static Command valueOf(String commandName) {
+        for (Command command : COMMANDS) {
+            if (command.getName().equals(commandName)) {
+                return command;
+            }
+        }
+        return null;
+    }
+
+    abstract public String getOptionSyntax();
+
+    abstract public String getName();
+
+    abstract public String getDescription();
+
+    abstract public void displayOptionUsage();
+
+    abstract public void execute(Deque<String> options);
+
+    final protected void userFailed(String message) {
+        println();
+        println(message);
+        displayUsage();
+        throw new IllegalArgumentException(message);
+    }
+
+    final protected void ensureMaxArgumentCount(Deque<String> options, int maxCount) {
+        if (options.size() > maxCount) {
+            userFailed("Too many arguments");
+        }
+    }
+
+    final protected void ensureMinArgumentCount(Deque<String> options, int minCount) {
+        if (options.size() < minCount) {
+            userFailed("Too few arguments");
+        }
+    }
+
+    final protected void ensureFileExist(Path file) {
+        if (!Files.exists(file)) {
+            userFailed("Could not find file " + file);
+        }
+    }
+
+    final protected Path ensureFileDoesNotExist(Path file) {
+        if (Files.exists(file)) {
+            userFailed("File " + file + " already exists");
+        }
+        return file;
+    }
+
+    final protected void ensureJFRFile(Path path) {
+        if (!path.toString().endsWith(".jfr")) {
+            userFailed("Filename must end with .jfr");
+        }
+    }
+
+    final protected void displayUsage() {
+        String javaText = "java " + Execute.class.getName();
+        println();
+        println("Usage: " + javaText + " " + getName() + " " + getOptionSyntax());
+        println();
+        displayOptionUsage();
+    }
+
+    final protected void println() {
+        System.out.println();
+    }
+
+    final protected void print(String text) {
+        System.out.print(text);
+    }
+
+    final protected void println(String text) {
+        System.out.println(text);
+    }
+
+    private static List<Command> createCommands() {
+        List<Command> commands = new ArrayList<>();
+        commands.add(new PrintCommand());
+        commands.add(new SummaryCommand());
+        commands.add(new ReconstructCommand());
+        commands.add(new SplitCommand());
+        commands.add(HELP);
+        return Collections.unmodifiableList(commands);
+    }
+}