diff -r 4ebc2e2fb97c -r 71c04702a3d5 src/java.base/share/classes/sun/nio/ch/CompletedFuture.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/java.base/share/classes/sun/nio/ch/CompletedFuture.java	Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,96 @@
+/*
+ * Copyright (c) 2008, 2010, 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 sun.nio.ch;
+
+import java.util.concurrent.Future;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.ExecutionException;
+import java.io.IOException;
+
+/**
+ * A Future representing the result of an I/O operation that has already
+ * completed.
+ */
+
+final class CompletedFuture<V> implements Future<V> {
+    private final V result;
+    private final Throwable exc;
+
+    private CompletedFuture(V result, Throwable exc) {
+        this.result = result;
+        this.exc = exc;
+    }
+
+    static <V> CompletedFuture<V> withResult(V result) {
+        return new CompletedFuture<V>(result, null);
+    }
+
+    static <V> CompletedFuture<V> withFailure(Throwable exc) {
+        // exception must be IOException or SecurityException
+        if (!(exc instanceof IOException) && !(exc instanceof SecurityException))
+            exc = new IOException(exc);
+        return new CompletedFuture<V>(null, exc);
+    }
+
+    static <V> CompletedFuture<V> withResult(V result, Throwable exc) {
+        if (exc == null) {
+            return withResult(result);
+        } else {
+            return withFailure(exc);
+        }
+    }
+
+    @Override
+    public V get() throws ExecutionException {
+        if (exc != null)
+            throw new ExecutionException(exc);
+        return result;
+    }
+
+    @Override
+    public V get(long timeout, TimeUnit unit) throws ExecutionException {
+        if (unit == null)
+            throw new NullPointerException();
+        if (exc != null)
+            throw new ExecutionException(exc);
+        return result;
+    }
+
+    @Override
+    public boolean isCancelled() {
+        return false;
+    }
+
+    @Override
+    public boolean isDone() {
+        return true;
+    }
+
+    @Override
+    public boolean cancel(boolean mayInterruptIfRunning) {
+        return false;
+    }
+}