--- /dev/null	2017-11-09 09:38:01.297999907 +0100
+++ new/test/jdk/jdk/jfr/jcmd/JcmdHelper.java	2018-04-09 18:36:36.257066153 +0200
@@ -0,0 +1,136 @@
+/*
+ * Copyright (c) 2015, 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.jcmd;
+
+import java.io.File;
+import java.util.Arrays;
+import java.util.stream.Collectors;
+
+import jdk.test.lib.Asserts;
+import jdk.test.lib.dcmd.CommandExecutor;
+import jdk.test.lib.dcmd.PidJcmdExecutor;
+import jdk.test.lib.process.OutputAnalyzer;
+
+public class JcmdHelper {
+
+    // Wait until recording's state became running
+    public static void waitUntilRunning(String name) throws Exception {
+        long timeoutAt = System.currentTimeMillis() + 10000;
+        while (true) {
+            OutputAnalyzer output = jcmdCheck(name, false);
+            try {
+                // The expected output can look like this:
+                // Recording: recording=1 name="Recording 1" (running)
+                output.shouldMatch("^Recording: recording=\\d+\\s+name=\"" + name
+                        + "\".*\\W{1}running\\W{1}");
+                return;
+            } catch (RuntimeException e) {
+                if (System.currentTimeMillis() > timeoutAt) {
+                    Asserts.fail("Recording not started: " + name);
+                }
+                Thread.sleep(100);
+            }
+        }
+    }
+
+    // Wait until default recording's state became running
+    public static void waitUntilDefaultRecordingRunning() throws Exception {
+        while (true) {
+            OutputAnalyzer output = jcmd("JFR.check", "recording=0");
+            try {
+                output.shouldContain("Recording: recording=0 name=\"HotSpot default\" (running)");
+                return;
+            } catch (RuntimeException e) {
+                Thread.sleep(100);
+            }
+        }
+    }
+
+    public static void stopAndCheck(String name) throws Exception {
+        jcmd("JFR.stop", "name=\"" + name + "\"");
+        assertRecordingNotRunning(name);
+    }
+
+    public static void stopWriteToFileAndCheck(String name, File file) throws Exception {
+        OutputAnalyzer output = jcmd("JFR.stop",
+                "name=\"" + name + "\"",
+                "filename=\"" + file.getAbsolutePath() + "\"");
+        JcmdAsserts.assertStoppedAndWrittenTo(output, name, file);
+        assertRecordingNotRunning(name);
+    }
+
+    public static void stopCompressAndCheck(String name, File file) throws Exception {
+        OutputAnalyzer output = jcmd("JFR.stop",
+                "name=\"" + name + "\"",
+                "compress=true",
+                "filename=\"" + file.getAbsolutePath() + "\"");
+        JcmdAsserts.assertStoppedAndWrittenTo(output, name, file);
+        checkAndAssertNoRecordingsAvailable();
+    }
+
+    public static void stopDefaultRecordingAndCheck() throws Exception {
+        OutputAnalyzer output = jcmd("JFR.stop", "recording=0");
+        JcmdAsserts.assertStoppedDefaultRecording(output);
+        checkAndAssertNoRecordingsAvailable();
+    }
+
+    public static void checkAndAssertNoRecordingsAvailable() throws Exception {
+        OutputAnalyzer output = jcmd("JFR.check");
+        JcmdAsserts.assertNoRecordingsAvailable(output);
+    }
+
+    public static void assertRecordingNotExist(String name) throws Exception {
+        OutputAnalyzer output = jcmdCheck(name, false);
+        JcmdAsserts.assertRecordingNotExist(output, name);
+    }
+
+    public static void assertRecordingNotRunning(String name) throws Exception {
+        OutputAnalyzer output = jcmdCheck(name, false);
+        JcmdAsserts.assertRecordingNotRunning(output, name);
+    }
+
+    public static void assertRecordingIsRunning(String name) throws Exception {
+        OutputAnalyzer output = jcmdCheck(name, false);
+        JcmdAsserts.assertRecordingIsRunning(output, name);
+    }
+
+    public static OutputAnalyzer jcmd(int expectedExitValue, String... args) {
+        String argsString = Arrays.stream(args).collect(Collectors.joining(" "));
+        CommandExecutor executor = new PidJcmdExecutor();
+        OutputAnalyzer oa = executor.execute(argsString);
+        oa.shouldHaveExitValue(expectedExitValue);
+        return oa;
+    }
+
+    public static OutputAnalyzer jcmd(String... args) {
+        return jcmd(0, args);
+    }
+
+
+    public static OutputAnalyzer jcmdCheck(String recordingName, boolean verbose) {
+        return jcmd("JFR.check", "name=" + recordingName, "verbose=" + verbose);
+    }
+}