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diff --git a/grpc/src/core/ext/transport/binder/client/endpoint_binder_pool.h b/grpc/src/core/ext/transport/binder/client/endpoint_binder_pool.h
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+// Copyright 2021 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef GRPC_CORE_EXT_TRANSPORT_BINDER_CLIENT_ENDPOINT_BINDER_POOL_H
+#define GRPC_CORE_EXT_TRANSPORT_BINDER_CLIENT_ENDPOINT_BINDER_POOL_H
+
+#include <grpc/support/port_platform.h>
+
+#include <functional>
+#include <string>
+
+#include "absl/container/flat_hash_map.h"
+
+#include "src/core/ext/transport/binder/wire_format/binder.h"
+#include "src/core/lib/gprpp/sync.h"
+
+namespace grpc_binder {
+
+// This class serves as a buffer of endpoint binders between C++ and
+// Java. `AddEndpointBinder` will be indirectly invoked by Java code, and
+// `GetEndpointBinder` is for C++ code to register callback to get endpoint
+// binder when become available. This simplifies JNI related threading issues
+// since both side only need to interact with this buffer in non-blocking
+// manner and avoids cross-language callbacks.
+class EndpointBinderPool {
+ public:
+  // Invokes the callback when the binder corresponding to the conn_id become
+  // available. If the binder is already available, invokes the callback
+  // immediately.
+  // Ownership of the endpoint binder will be transferred to the callback
+  // function and it will be removed from the pool
+  void GetEndpointBinder(
+      std::string conn_id,
+      std::function<void(std::unique_ptr<grpc_binder::Binder>)> cb);
+
+  // Add an endpoint binder to the pool
+  void AddEndpointBinder(std::string conn_id,
+                         std::unique_ptr<grpc_binder::Binder> b);
+
+ private:
+  grpc_core::Mutex m_;
+  absl::flat_hash_map<std::string, std::unique_ptr<grpc_binder::Binder>>
+      binder_map_ ABSL_GUARDED_BY(m_);
+  absl::flat_hash_map<std::string,
+                      std::function<void(std::unique_ptr<grpc_binder::Binder>)>>
+      pending_requests_ ABSL_GUARDED_BY(m_);
+};
+
+// Returns the singleton
+EndpointBinderPool* GetEndpointBinderPool();
+
+}  // namespace grpc_binder
+
+#endif  // GRPC_CORE_EXT_TRANSPORT_BINDER_CLIENT_ENDPOINT_BINDER_POOL_H