--- a/jdk/src/share/classes/sun/nio/ch/AsynchronousFileChannelImpl.java	Sat Aug 22 17:40:18 2009 +0100
+++ b/jdk/src/share/classes/sun/nio/ch/AsynchronousFileChannelImpl.java	Sun Aug 23 12:53:45 2009 +0100
@@ -25,8 +25,10 @@
 
 package sun.nio.ch;
 
+import java.nio.ByteBuffer;
 import java.nio.channels.*;
 import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Future;
 import java.util.concurrent.locks.*;
 import java.io.FileDescriptor;
 import java.io.IOException;
@@ -101,6 +103,33 @@
 
     // -- file locking --
 
+    abstract <A> Future<FileLock> implLock(long position,
+                                           long size,
+                                           boolean shared,
+                                           A attachment,
+                                           CompletionHandler<FileLock,? super A> handler);
+
+    @Override
+    public final Future<FileLock> lock(long position,
+                                       long size,
+                                       boolean shared)
+
+    {
+        return implLock(position, size, shared, null, null);
+    }
+
+    @Override
+    public final <A> void lock(long position,
+                               long size,
+                               boolean shared,
+                               A attachment,
+                               CompletionHandler<FileLock,? super A> handler)
+    {
+        if (handler == null)
+            throw new NullPointerException("'handler' is null");
+        implLock(position, size, shared, attachment, handler);
+    }
+
     private volatile FileLockTable fileLockTable;
 
     final void ensureFileLockTableInitialized() throws IOException {
@@ -175,4 +204,50 @@
             end();
         }
     }
+
+
+    // -- reading and writing --
+
+    abstract <A> Future<Integer> implRead(ByteBuffer dst,
+                                         long position,
+                                         A attachment,
+                                         CompletionHandler<Integer,? super A> handler);
+
+    @Override
+    public final Future<Integer> read(ByteBuffer dst, long position) {
+        return implRead(dst, position, null, null);
+    }
+
+    @Override
+    public final <A> void read(ByteBuffer dst,
+                               long position,
+                               A attachment,
+                               CompletionHandler<Integer,? super A> handler)
+    {
+        if (handler == null)
+            throw new NullPointerException("'handler' is null");
+        implRead(dst, position, attachment, handler);
+    }
+
+    abstract <A> Future<Integer> implWrite(ByteBuffer src,
+                                           long position,
+                                           A attachment,
+                                           CompletionHandler<Integer,? super A> handler);
+
+
+    @Override
+    public final Future<Integer> write(ByteBuffer src, long position) {
+        return implWrite(src, position, null, null);
+    }
+
+    @Override
+    public final <A> void write(ByteBuffer src,
+                                long position,
+                                A attachment,
+                                CompletionHandler<Integer,? super A> handler)
+    {
+        if (handler == null)
+            throw new NullPointerException("'handler' is null");
+        implWrite(src, position, attachment, handler);
+    }
 }