--- /dev/null	2017-10-28 22:49:55.551349757 -0700
+++ new/test/jdk/java/net/httpclient/websocket/jdk.incubator.httpclient/jdk/incubator/http/internal/websocket/SendingTest.java	2017-11-30 04:06:18.604256562 -0800
@@ -0,0 +1,164 @@
+/*
+ * Copyright (c) 2017, 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.
+ *
+ * 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.incubator.http.internal.websocket;
+
+import jdk.incubator.http.WebSocket;
+import org.testng.annotations.Test;
+
+import java.net.URI;
+import java.nio.ByteBuffer;
+import java.util.Random;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.CompletionStage;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicInteger;
+
+import static jdk.incubator.http.WebSocket.NORMAL_CLOSURE;
+import static jdk.incubator.http.internal.websocket.TestSupport.assertCompletesExceptionally;
+import static jdk.incubator.http.internal.websocket.WebSocketImpl.newInstance;
+import static org.testng.Assert.assertEquals;
+
+public class SendingTest {
+
+    @Test
+    public void sendTextImmediately() {
+        MockTransmitter t = new MockTransmitter() {
+            @Override
+            protected CompletionStage<?> whenSent() {
+                return CompletableFuture.completedFuture(null);
+            }
+        };
+        WebSocket ws = newWebSocket(t);
+        CompletableFuture.completedFuture(ws)
+                .thenCompose(w -> w.sendText("1", true))
+                .thenCompose(w -> w.sendText("2", true))
+                .thenCompose(w -> w.sendText("3", true))
+                .join();
+
+        assertEquals(t.queue().size(), 3);
+    }
+
+    @Test
+    public void sendTextWithDelay() {
+        MockTransmitter t = new MockTransmitter() {
+            @Override
+            protected CompletionStage<?> whenSent() {
+                return new CompletableFuture<>()
+                        .completeOnTimeout(null, 1, TimeUnit.SECONDS);
+            }
+        };
+        WebSocket ws = newWebSocket(t);
+        CompletableFuture.completedFuture(ws)
+                .thenCompose(w -> w.sendText("1", true))
+                .thenCompose(w -> w.sendText("2", true))
+                .thenCompose(w -> w.sendText("3", true))
+                .join();
+
+        assertEquals(t.queue().size(), 3);
+    }
+
+    @Test
+    public void sendTextMixedDelay() {
+        Random r = new Random();
+
+        MockTransmitter t = new MockTransmitter() {
+            @Override
+            protected CompletionStage<?> whenSent() {
+                return r.nextBoolean() ?
+                        new CompletableFuture<>().completeOnTimeout(null, 1, TimeUnit.SECONDS) :
+                        CompletableFuture.completedFuture(null);
+            }
+        };
+        WebSocket ws = newWebSocket(t);
+        CompletableFuture.completedFuture(ws)
+                .thenCompose(w -> w.sendText("1", true))
+                .thenCompose(w -> w.sendText("2", true))
+                .thenCompose(w -> w.sendText("3", true))
+                .thenCompose(w -> w.sendText("4", true))
+                .thenCompose(w -> w.sendText("5", true))
+                .thenCompose(w -> w.sendText("6", true))
+                .thenCompose(w -> w.sendText("7", true))
+                .thenCompose(w -> w.sendText("8", true))
+                .thenCompose(w -> w.sendText("9", true))
+                .join();
+
+        assertEquals(t.queue().size(), 9);
+    }
+
+    @Test
+    public void sendControlMessagesConcurrently() {
+
+        CompletableFuture<?> first = new CompletableFuture<>();
+
+        MockTransmitter t = new MockTransmitter() {
+
+            final AtomicInteger i = new AtomicInteger();
+
+            @Override
+            protected CompletionStage<?> whenSent() {
+                if (i.incrementAndGet() == 1) {
+                    return first;
+                } else {
+                    return CompletableFuture.completedFuture(null);
+                }
+            }
+        };
+        WebSocket ws = newWebSocket(t);
+
+        CompletableFuture<?> cf1 = ws.sendPing(ByteBuffer.allocate(0));
+        CompletableFuture<?> cf2 = ws.sendPong(ByteBuffer.allocate(0));
+        CompletableFuture<?> cf3 = ws.sendClose(NORMAL_CLOSURE, "");
+        CompletableFuture<?> cf4 = ws.sendClose(NORMAL_CLOSURE, "");
+        CompletableFuture<?> cf5 = ws.sendPing(ByteBuffer.allocate(0));
+        CompletableFuture<?> cf6 = ws.sendPong(ByteBuffer.allocate(0));
+
+        first.complete(null);
+        // Don't care about exceptional completion, only that all of them have
+        // completed
+        CompletableFuture.allOf(cf1, cf2, cf3, cf4, cf5, cf6)
+                .handle((v, e) -> null).join();
+
+        cf3.join(); /* Check that sendClose has completed normally */
+        cf4.join(); /* Check that repeated sendClose has completed normally */
+        assertCompletesExceptionally(IllegalStateException.class, cf5);
+        assertCompletesExceptionally(IllegalStateException.class, cf6);
+
+        assertEquals(t.queue().size(), 3); // 6 minus 3 that were not accepted
+    }
+
+    private static WebSocket newWebSocket(Transmitter transmitter) {
+        URI uri = URI.create("ws://localhost");
+        String subprotocol = "";
+        TransportSupplier transport = new MockTransport() {
+            @Override
+            public Transmitter transmitter() {
+                return transmitter;
+            }
+        };
+        return newInstance(uri,
+                           subprotocol,
+                           new MockListener(Long.MAX_VALUE),
+                           transport);
+    }
+}