--- old/src/java.base/share/classes/java/lang/Readable.java	2017-11-13 23:14:28.000000000 +0100
+++ new/src/java.base/share/classes/java/lang/Readable.java	2017-11-13 23:14:27.000000000 +0100
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2003, 2013, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2003, 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
@@ -26,6 +26,8 @@
 package java.lang;
 
 import java.io.IOException;
+import java.nio.CharBuffer;
+import java.util.Objects;
 
 /**
  * A {@code Readable} is a source of characters. Characters from
@@ -50,4 +52,68 @@
      * @throws java.nio.ReadOnlyBufferException if cb is a read only buffer
      */
     public int read(java.nio.CharBuffer cb) throws IOException;
+
+    /**
+     * Reads all characters from this source and appends them to a destination
+     * in the order in which they are read. On return, the source of characters
+     * will be at its end.
+     * <p>
+     * This method may block indefinitely while reading from the source or
+     * writing to the destination. If the source or destination is
+     * {@link AutoCloseable closeable}, then the behavior when either is
+     * <i>asynchronously closed</i>, or the thread is interrupted during the
+     * transfer, is highly implementation-dependent and hence unspecified.
+     * <p>
+     * If an I/O error occurs during the operation, then not all characters
+     * might have been transferred and the source or destination could be
+     * left in an inconsistent state. The caller of this method should therefore
+     * ensure in such a case that measures are taken to release any resources
+     * held by the source and destination.
+     * <p>
+     * Depending on which class implements the appendable, there may be a limit
+     * of data that can written to which in turn could lead to an exception.
+     *
+     * @implSpec
+     * The default implementation invokes the read method to read all characters
+     * from this source and invokes the {@link Appendable#append(CharSequence, int, int)}
+     * method to write all characters to the appendable.
+     *
+     * The default implementation behaves as if:
+     * <pre>{@code
+     *     long transferred = 0;
+     *     CharBuffer buffer = CharBuffer.allocate(8192);
+     *     int read;
+     *     while ((read = this.read(buffer)) >= 0) {
+     *         buffer.rewind();
+     *         out.append(buffer, 0, read);
+     *         transferred += read;
+     *     }
+     *     return transferred;
+     * }</pre>
+     *
+     * @implNote
+     * The default implementation should usually be overridden in cases where
+     * the implementer is already a {@link CharSequence} or its data is already
+     * available in the internal representation to avoid the extra overhead of
+     * a buffer in order to transfer its data to the destination.
+     *
+     * @param  out the appendable, non-null
+     * @return the number of characters transferred
+     * @throws IOException if an I/O error occurs when reading or writing
+     * @throws NullPointerException if {@code out} is {@code null}
+     *
+     * @since 10
+     */
+    public default long transferTo(Appendable out) throws IOException {
+        Objects.requireNonNull(out, "out");
+        long transferred = 0;
+        CharBuffer buffer = CharBuffer.allocate(8192);
+        int read;
+        while ((read = this.read(buffer)) >= 0) {
+            buffer.rewind();
+            out.append(buffer, 0, read);
+            transferred += read;
+        }
+        return transferred;
+    }
 }
--- old/src/java.base/share/classes/java/nio/X-Buffer.java.template	2017-11-13 23:14:29.000000000 +0100
+++ new/src/java.base/share/classes/java/nio/X-Buffer.java.template	2017-11-13 23:14:28.000000000 +0100
@@ -29,6 +29,7 @@
 
 #if[char]
 import java.io.IOException;
+import java.util.Objects;
 #end[char]
 #if[streamableType]
 import java.util.Spliterator;
@@ -1548,6 +1549,42 @@
         return put($x$);
     }
 
+    /**
+     * {@inheritDoc}
+     *
+     * @implSpec
+     * The implementation is using two strategies of transferring data from the
+     * actual source to the given destination. If the given {@link Appendable}
+     * is a {@link CharBuffer} the transfer uses the {@code put(CharBuffer)}
+     * method to transfer it's data if possible. For the other cases source
+     * is passed into the {@link Appendable#append(CharSequence, int, int)}
+     * method along with the current position and data length.
+     *
+     * @param  out the appendable, non-null
+     * @return the number of characters transferred
+     * @throws IOException if an I/O error occurs when reading or writing
+     * @throws NullPointerException if {@code out} is {@code null}
+     * @throws BufferOverflowException if there is insufficient space in out
+     *         buffer for the remaining chars in the source buffer
+     * @throws IllegalArgumentException if out is this buffer
+     * @throws ReadOnlyBufferException if out is a read-only buffer
+     *
+     * @since 10
+     */
+    @Override
+    public long transferTo(Appendable out) throws IOException {
+        Objects.requireNonNull(out, "out");
+        if (this == out) {
+            throw new IllegalArgumentException("Illegal transfer of a buffer to itself");
+        }
+        int length = remaining();
+        if (out instanceof CharBuffer) {
+            ((CharBuffer)out).put(this);
+        } else {
+            out.append(this, position(), length);
+        }
+        return length;
+    }
 #end[char]
 
 
--- /dev/null	2017-11-13 23:14:30.000000000 +0100
+++ new/test/jdk/java/lang/Readable/TransferTo.java	2017-11-13 23:14:29.000000000 +0100
@@ -0,0 +1,352 @@
+/*
+ * 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.
+ */
+
+import java.io.*;
+import java.util.Arrays;
+import java.util.Random;
+
+import jdk.test.lib.RandomFactory;
+
+import static java.lang.String.format;
+
+/*
+ * @test
+ * @bug 8067661
+ * @summary tests whether java.lang.Readable.transferTo default implementation
+ *          conforms to the contract defined in the javadoc
+ * @library /test/lib
+ * @build jdk.test.lib.RandomFactory
+ * @run main TransferTo
+ * @key randomness
+ */
+public class TransferTo {
+
+    private static Random generator = RandomFactory.getRandom();
+
+    public static void main(String[] args) throws IOException {
+        ifOutIsNullThenNpeIsThrown();
+        ifExceptionInInputNeitherSideIsClosed();
+        ifExceptionInOutputNeitherSideIsClosed();
+        onReturnNeitherSideIsClosed();
+        onReturnInputIsAtEnd();
+        contents();
+    }
+
+    private static void ifOutIsNullThenNpeIsThrown() throws IOException {
+        try (Reader in = input()) {
+            assertThrowsNPE(() -> in.transferTo(null), "out");
+        }
+
+        try (Reader in = input((char) 1)) {
+            assertThrowsNPE(() -> in.transferTo(null), "out");
+        }
+
+        try (Reader in = input((char) 1, (char) 2)) {
+            assertThrowsNPE(() -> in.transferTo(null), "out");
+        }
+
+        Reader in = null;
+        try {
+            Reader fin = in = new ThrowingReader();
+            // null check should precede everything else:
+            // Reader shouldn't be touched if Writer is null
+            assertThrowsNPE(() -> fin.transferTo(null), "out");
+        } finally {
+            if (in != null)
+                try {
+                    in.close();
+                } catch (IOException ignored) { }
+        }
+    }
+
+    private static void ifExceptionInInputNeitherSideIsClosed()
+            throws IOException {
+        transferToThenCheckIfAnyClosed(input(0, new char[]{1, 2, 3}), output());
+        transferToThenCheckIfAnyClosed(input(1, new char[]{1, 2, 3}), output());
+        transferToThenCheckIfAnyClosed(input(2, new char[]{1, 2, 3}), output());
+    }
+
+    private static void ifExceptionInOutputNeitherSideIsClosed()
+            throws IOException {
+        transferToThenCheckIfAnyClosed(input(new char[]{1, 2, 3}), output(0));
+        transferToThenCheckIfAnyClosed(input(new char[]{1, 2, 3}), output(1));
+        transferToThenCheckIfAnyClosed(input(new char[]{1, 2, 3}), output(2));
+    }
+
+    private static void transferToThenCheckIfAnyClosed(Reader input,
+                                                       Writer output)
+            throws IOException {
+        try (CloseLoggingReader in = new CloseLoggingReader(input);
+             CloseLoggingWriter out =
+                     new CloseLoggingWriter(output)) {
+            boolean thrown = false;
+            try {
+                in.transferTo(out);
+            } catch (IOException ignored) {
+                thrown = true;
+            }
+            if (!thrown)
+                throw new AssertionError();
+
+            if (in.wasClosed() || out.wasClosed()) {
+                throw new AssertionError();
+            }
+        }
+    }
+
+    private static void onReturnNeitherSideIsClosed()
+            throws IOException {
+        try (CloseLoggingReader in =
+                     new CloseLoggingReader(input(new char[]{1, 2, 3}));
+             CloseLoggingWriter out =
+                     new CloseLoggingWriter(output())) {
+
+            in.transferTo(out);
+
+            if (in.wasClosed() || out.wasClosed()) {
+                throw new AssertionError();
+            }
+        }
+    }
+
+    private static void onReturnInputIsAtEnd() throws IOException {
+        try (Reader in = input(new char[]{1, 2, 3});
+             Writer out = output()) {
+
+            in.transferTo(out);
+
+            if (in.read() != -1) {
+                throw new AssertionError();
+            }
+        }
+    }
+
+    private static void contents() throws IOException {
+        checkTransferredContents(new char[0]);
+        checkTransferredContents(createRandomChars(1024, 4096));
+        // to span through several batches
+        checkTransferredContents(createRandomChars(16384, 16384));
+    }
+
+    private static void checkTransferredContents(char[] chars)
+            throws IOException {
+        try (Reader in = input(chars);
+             StringWriter out = new StringWriter()) {
+            in.transferTo(out);
+
+            char[] outChars = out.toString().toCharArray();
+            if (!Arrays.equals(chars, outChars)) {
+                throw new AssertionError(
+                        format("chars.length=%s, outChars.length=%s",
+                                chars.length, outChars.length));
+            }
+        }
+    }
+
+    private static char[] createRandomChars(int min, int maxRandomAdditive) {
+        char[] chars = new char[min + generator.nextInt(maxRandomAdditive)];
+        for (int index=0; index<chars.length; index++) {
+            chars[index] = (char)generator.nextInt();
+        }
+        return chars;
+    }
+
+    private static Writer output() {
+        return output(-1);
+    }
+
+    private static Writer output(int exceptionPosition) {
+        return new Writer() {
+
+            int pos;
+
+            @Override
+            public void write(int b) throws IOException {
+                if (pos++ == exceptionPosition)
+                    throw new IOException();
+            }
+
+            @Override
+            public void write(char[] chars, int off, int len) throws IOException {
+                for (int i=0; i<len; i++) {
+                    write(chars[off + i]);
+                }
+            }
+
+            @Override
+            public Writer append(CharSequence csq, int start, int end) throws IOException {
+                for (int i = start; i < end; i++) {
+                    write(csq.charAt(i));
+                }
+                return this;
+            }
+
+            @Override
+            public void flush() throws IOException {
+            }
+
+            @Override
+            public void close() throws IOException {
+            }
+        };
+    }
+
+    private static Reader input(char... chars) {
+        return input(-1, chars);
+    }
+
+    private static Reader input(int exceptionPosition, char... chars) {
+        return new Reader() {
+
+            int pos;
+
+            @Override
+            public int read() throws IOException {
+                if (pos == exceptionPosition) {
+                    throw new IOException();
+                }
+
+                if (pos >= chars.length)
+                    return -1;
+                return chars[pos++];
+            }
+
+            @Override
+            public int read(char[] cbuf, int off, int len) throws IOException {
+                int c = read();
+                if (c == -1) {
+                    return -1;
+                }
+                cbuf[off] = (char)c;
+
+                int i = 1;
+                for (; i < len ; i++) {
+                    c = read();
+                    if (c == -1) {
+                        break;
+                    }
+                    cbuf[off + i] = (char)c;
+                }
+                return i;
+            }
+
+            @Override
+            public void close() throws IOException {
+            }
+        };
+    }
+
+    private static class ThrowingReader extends Reader {
+
+        boolean closed;
+
+        @Override
+        public int read(char[] b, int off, int len) throws IOException {
+            throw new IOException();
+        }
+
+        @Override
+        public void close() throws IOException {
+            if (!closed) {
+                closed = true;
+                throw new IOException();
+            }
+        }
+        @Override
+        public int read() throws IOException {
+            throw new IOException();
+        }
+    }
+
+    private static class CloseLoggingReader extends FilterReader {
+
+        boolean closed;
+
+        CloseLoggingReader(Reader in) {
+            super(in);
+        }
+
+        @Override
+        public void close() throws IOException {
+            closed = true;
+            super.close();
+        }
+
+        boolean wasClosed() {
+            return closed;
+        }
+    }
+
+    private static class CloseLoggingWriter extends FilterWriter {
+
+        boolean closed;
+
+        CloseLoggingWriter(Writer out) {
+            super(out);
+        }
+
+        @Override
+        public void close() throws IOException {
+            closed = true;
+            super.close();
+        }
+
+        boolean wasClosed() {
+            return closed;
+        }
+    }
+
+    public interface Thrower {
+        public void run() throws Throwable;
+    }
+
+    public static void assertThrowsNPE(Thrower thrower, String message) {
+        assertThrows(thrower, NullPointerException.class, message);
+    }
+
+    public static <T extends Throwable> void assertThrows(Thrower thrower,
+                                                          Class<T> throwable,
+                                                          String message) {
+        Throwable thrown;
+        try {
+            thrower.run();
+            thrown = null;
+        } catch (Throwable caught) {
+            thrown = caught;
+        }
+
+        if (!throwable.isInstance(thrown)) {
+            String caught = thrown == null ?
+                    "nothing" : thrown.getClass().getCanonicalName();
+            throw new AssertionError(
+                    format("Expected to catch %s, but caught %s",
+                            throwable, caught), thrown);
+        }
+
+        if (thrown != null && !message.equals(thrown.getMessage())) {
+            throw new AssertionError(
+                    format("Expected exception message to be '%s', but it's '%s'",
+                            message, thrown.getMessage()));
+        }
+    }
+}
--- /dev/null	2017-11-13 23:14:31.000000000 +0100
+++ new/test/jdk/java/nio/Buffer/TransferTo.java	2017-11-13 23:14:30.000000000 +0100
@@ -0,0 +1,138 @@
+/*
+ * 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 source 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 source 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 Franklsource 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.
+ */
+
+import java.io.IOException;
+import java.io.StringWriter;
+import java.nio.BufferOverflowException;
+import java.nio.CharBuffer;
+import java.nio.ReadOnlyBufferException;
+import java.util.Objects;
+import java.util.function.Supplier;
+
+import static java.lang.String.format;
+
+/*
+ * @test
+ * @bug 8067661
+ * @summary tests whether java.nio.CharBuffer.transferTo conforms to its
+ *          contract defined source the javadoc
+ */
+public class TransferTo {
+
+    public static void main(String[] args) throws IOException {
+        ifOutIsNullThenNpeIsThrown();
+        ifOutIsSelfThenIllegalAccessExceptionIsThrown();
+        targetIsAppendable();
+        targetIsCharBuffer();
+        targetIsTooSmallCharBuffer();
+        targetIsReadOnlyCharBuffer();
+    }
+
+    private static void ifOutIsNullThenNpeIsThrown() {
+        CharBuffer source = createSource();
+        assertThrowsNPE(() -> source.transferTo(null), "out");
+    }
+
+    private static void ifOutIsSelfThenIllegalAccessExceptionIsThrown() {
+        CharBuffer source = createSource();
+        assertThrows(() -> source.transferTo(source), IllegalArgumentException.class, "Illegal transfer of a buffer to itself");
+    }
+
+    private static void targetIsAppendable() throws IOException {
+        CharBuffer source = createSource();
+        StringWriter target = new StringWriter();
+        source.transferTo(target);
+        assertEquals(source, () -> target.toString());
+    }
+
+    private static void targetIsCharBuffer() throws IOException {
+        CharBuffer source = createSource();
+        CharBuffer target = CharBuffer.allocate(source.limit());
+        source.transferTo(target);
+        assertEquals(source, () -> {
+            target.rewind();
+            return target.toString();
+        });
+    }
+
+    private static void targetIsTooSmallCharBuffer() {
+        CharBuffer source = createSource();
+        CharBuffer target = CharBuffer.allocate(source.limit() - 1);
+        assertThrows(() -> source.transferTo(target), BufferOverflowException.class, null);
+    }
+
+    private static void targetIsReadOnlyCharBuffer() {
+        CharBuffer source = createSource();
+        CharBuffer target = CharBuffer.allocate(source.limit()).asReadOnlyBuffer();
+        assertThrows(() -> source.transferTo(target), ReadOnlyBufferException.class, null);
+    }
+
+    private static CharBuffer createSource() {
+        CharBuffer buffer = CharBuffer.wrap("mary had a little lamb");
+        buffer.rewind();
+        return buffer;
+    }
+
+    private static void assertEquals(CharBuffer expected, Supplier<String> testValueSupplier) {
+        expected.rewind();
+        String correct = expected.toString();
+        String tested = testValueSupplier.get();
+        if (!correct.equals(tested)) {
+            throw new AssertionError(format("Expected: '%s', but got '%s'", correct, tested));
+        }
+    }
+
+    public interface Thrower {
+        public void run() throws Throwable;
+    }
+
+    public static void assertThrowsNPE(Thrower thrower, String message) {
+        assertThrows(thrower, NullPointerException.class, message);
+    }
+
+    public static <T extends Throwable> void assertThrows(Thrower thrower,
+                                                          Class<T> throwable,
+                                                          String message) {
+        Throwable thrown;
+        try {
+            thrower.run();
+            thrown = null;
+        } catch (Throwable caught) {
+            thrown = caught;
+        }
+
+        if (!throwable.isInstance(thrown)) {
+            String caught = thrown == null ?
+                    "nothing" : thrown.getClass().getCanonicalName();
+            throw new AssertionError(
+                    format("Expected to catch %s, but caught %s",
+                            throwable, caught), thrown);
+        }
+
+        if (thrown != null && !Objects.equals(message, thrown.getMessage())) {
+            throw new AssertionError(
+                    format("Expected exception message to be '%s', but it's '%s'",
+                            message, thrown.getMessage()));
+        }
+    }
+}