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diff --git a/include/grpc++/stream.h b/include/grpc++/stream.h
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+/*
+ *
+ * Copyright 2014, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#ifndef __GRPCPP_STREAM_H__
+#define __GRPCPP_STREAM_H__
+
+#include <grpc++/stream_context_interface.h>
+#include <grpc++/status.h>
+#include <grpc/support/log.h>
+
+namespace grpc {
+
+// Common interface for all client side streaming.
+class ClientStreamingInterface {
+ public:
+  virtual ~ClientStreamingInterface() {}
+
+  // Try to cancel the stream. Wait() still needs to be called to get the final
+  // status. Cancelling after the stream has finished has no effects.
+  virtual void Cancel() = 0;
+
+  // Wait until the stream finishes, and return the final status. When the
+  // client side declares it has no more message to send, either implicitly or
+  // by calling WritesDone, it needs to make sure there is no more message to
+  // be received from the server, either implicitly or by getting a false from
+  // a Read(). Otherwise, this implicitly cancels the stream.
+  virtual const Status& Wait() = 0;
+};
+
+// An interface that yields a sequence of R messages.
+template <class R>
+class ReaderInterface {
+ public:
+  virtual ~ReaderInterface() {}
+
+  // Blocking read a message and parse to msg. Returns true on success.
+  // The method returns false when there will be no more incoming messages,
+  // either because the other side has called WritesDone or the stream has
+  // failed (or been cancelled).
+  virtual bool Read(R* msg) = 0;
+};
+
+// An interface that can be fed a sequence of W messages.
+template <class W>
+class WriterInterface {
+ public:
+  virtual ~WriterInterface() {}
+
+  // Blocking write msg to the stream. Returns true on success.
+  // Returns false when the stream has been closed.
+  virtual bool Write(const W& msg) = 0;
+};
+
+template <class R>
+class ClientReader : public ClientStreamingInterface,
+                     public ReaderInterface<R> {
+ public:
+  // Blocking create a stream and write the first request out.
+  explicit ClientReader(StreamContextInterface* context) : context_(context) {
+    GPR_ASSERT(context_);
+    context_->Start(true);
+    context_->Write(context_->request(), true);
+  }
+
+  ~ClientReader() { delete context_; }
+
+  virtual bool Read(R* msg) { return context_->Read(msg); }
+
+  virtual void Cancel() { context_->FinishStream(Status::Cancelled, true); }
+
+  virtual const Status& Wait() { return context_->Wait(); }
+
+ private:
+  StreamContextInterface* const context_;
+};
+
+template <class W>
+class ClientWriter : public ClientStreamingInterface,
+                     public WriterInterface<W> {
+ public:
+  // Blocking create a stream.
+  explicit ClientWriter(StreamContextInterface* context) : context_(context) {
+    GPR_ASSERT(context_);
+    context_->Start(false);
+  }
+
+  ~ClientWriter() { delete context_; }
+
+  virtual bool Write(const W& msg) {
+    return context_->Write(const_cast<W*>(&msg), false);
+  }
+
+  virtual void WritesDone() { context_->Write(nullptr, true); }
+
+  virtual void Cancel() { context_->FinishStream(Status::Cancelled, true); }
+
+  // Read the final response and wait for the final status.
+  virtual const Status& Wait() {
+    bool success = context_->Read(context_->response());
+    if (!success) {
+      Cancel();
+    } else {
+      success = context_->Read(nullptr);
+      if (success) {
+        Cancel();
+      }
+    }
+    return context_->Wait();
+  }
+
+ private:
+  StreamContextInterface* const context_;
+};
+
+// Client-side interface for bi-directional streaming.
+template <class W, class R>
+class ClientReaderWriter : public ClientStreamingInterface,
+                           public WriterInterface<W>,
+                           public ReaderInterface<R> {
+ public:
+  // Blocking create a stream.
+  explicit ClientReaderWriter(StreamContextInterface* context)
+      : context_(context) {
+    GPR_ASSERT(context_);
+    context_->Start(false);
+  }
+
+  ~ClientReaderWriter() { delete context_; }
+
+  virtual bool Read(R* msg) { return context_->Read(msg); }
+
+  virtual bool Write(const W& msg) {
+    return context_->Write(const_cast<W*>(&msg), false);
+  }
+
+  virtual void WritesDone() { context_->Write(nullptr, true); }
+
+  virtual void Cancel() { context_->FinishStream(Status::Cancelled, true); }
+
+  virtual const Status& Wait() { return context_->Wait(); }
+
+ private:
+  StreamContextInterface* const context_;
+};
+
+}  // namespace grpc
+
+#endif  // __GRPCPP_STREAM_H__