nearby: snapshot of cl/304428753

Signed-off-by: Alexey Polyudov <apolyudov@google.com>
Change-Id: I0023ac6e40456fc4a8169c3173bcbff3b5ccc476

cpp/platform/api2/future.h

@@ -0,0 +1,30 @@
+#ifndef PLATFORM_API2_FUTURE_H_
+#define PLATFORM_API2_FUTURE_H_
+
+#include "platform/exception.h"
+#include "absl/time/time.h"
+
+namespace location {
+namespace nearby {
+
+// A Future represents the result of an asynchronous computation.
+//
+// https://docs.oracle.com/javase/8/docs/api/java/util/concurrent/Future.html
+template <typename T>
+class Future {
+ public:
+  virtual ~Future() = default;
+
+  // throws Exception::kInterrupted, Exception::kExecution
+  virtual ExceptionOr<T> Get() = 0;
+
+  // throws Exception::kInterrupted, Exception::kExecution
+  // throws Exception::kTimeout if timeout is exceeded while waiting for
+  // result.
+  virtual ExceptionOr<T> Get(absl::Duration timeout) = 0;
+};
+
+}  // namespace nearby
+}  // namespace location
+
+#endif  // PLATFORM_API2_FUTURE_H_