1 files changed, 47 insertions, 5 deletions

diff --git a/libjava/java/nio/channels/Pipe.java b/libjava/java/nio/channels/Pipe.java
index 9c3c6cdc2de..22f3d156f68 100644
--- a/libjava/java/nio/channels/Pipe.java
+++ b/libjava/java/nio/channels/Pipe.java
@@ -40,40 +40,82 @@ package java.nio.channels;
 import java.nio.channels.spi.AbstractSelectableChannel;
 import java.nio.channels.spi.SelectorProvider;
 
+/**
+ * @author Michael Koch
+ * @since 1.4
+ */
 public abstract class Pipe
 {
   public abstract static class SinkChannel
     extends AbstractSelectableChannel
     implements WritableByteChannel, GatheringByteChannel
   {
-    protected SinkChannel(SelectorProvider provider)
+    /**
+     * Initializes the channel.
+     */
+    protected SinkChannel (SelectorProvider provider)
     {
       super (provider);
     }
+
+    /**
+     * Returns an operation set that is valid on this channel.
+     *
+     * The only valid operation on this channel is @see SelectionKey.OP_WRITE.
+     */
+    public final int validOps ()
+    {
+      return SelectionKey.OP_WRITE;
+    }
   }
 
   public abstract static class SourceChannel
     extends AbstractSelectableChannel
     implements ReadableByteChannel, ScatteringByteChannel
   {
-    protected SourceChannel(SelectorProvider provider)
+    /**
+     * Initializes the channel.
+     */
+    protected SourceChannel (SelectorProvider provider)
     {
       super (provider);
     }
+
+    /**
+     * Returns an operation set that is valid on this channel.
+     *
+     * The only valid operation on this channel is @see SelectionKey.OP_READ.
+     */
+    public final int validOps ()
+    {
+      return SelectionKey.OP_READ;
+    }
   }
-    
+
+  /**
+   * Initializes the pipe.
+   */
   protected Pipe()
   {
   }
 
   /**
+   * Opens a pipe.
+   * 
    * @exception IOException If an error occurs
    */
   public static Pipe open()
   {
-    return null;
+    return SelectorProvider.provider ().openPipe();
   }
-    
+
+  /**
+   * Returns a pipe's sink channel.
+   */
   public abstract Pipe.SinkChannel sink();
+
+  /**
+   * Returns a pipe's source channel
+   */
   public abstract Pipe.SourceChannel source();   
 }