From 550339c71b8d647cf63e6282a961caff9887f9d7 Mon Sep 17 00:00:00 2001
From: David Aurelio <davidaurelio@fb.com>
Date: Thu, 29 Mar 2018 22:48:44 -0700
Subject: [PATCH] Add `JReadableByteChannel`

Summary:
Adds `JReadableByteChannel`, which maps to `java.nio.ReadableByteChannel`.
This class is useful to stream data from Java to C++ memory (in conjunction with `JByteBuffer`).

Differential Revision: D7437312

fbshipit-source-id: 4979706148f0e20228f0f52341fb340497c24a8b
---
 .../src/main/jni/first-party/fb/Android.mk    |  1 +
 .../fb/include/fb/fbjni/ReadableByteChannel.h | 23 +++++++++++++++++++
 .../fb/jni/ReadableByteChannel.cpp            | 21 +++++++++++++++++
 3 files changed, 45 insertions(+)
 create mode 100644 ReactAndroid/src/main/jni/first-party/fb/include/fb/fbjni/ReadableByteChannel.h
 create mode 100644 ReactAndroid/src/main/jni/first-party/fb/jni/ReadableByteChannel.cpp

diff --git a/ReactAndroid/src/main/jni/first-party/fb/Android.mk b/ReactAndroid/src/main/jni/first-party/fb/Android.mk
index aaf198bce..4540eef1d 100644
--- a/ReactAndroid/src/main/jni/first-party/fb/Android.mk
+++ b/ReactAndroid/src/main/jni/first-party/fb/Android.mk
@@ -13,6 +13,7 @@ LOCAL_SRC_FILES:= \
        jni/jni_helpers.cpp \
        jni/LocalString.cpp \
        jni/OnLoad.cpp \
+       jni/ReadableByteChannel.cpp \
        jni/References.cpp \
        jni/WeakReference.cpp \
        log.cpp \
diff --git a/ReactAndroid/src/main/jni/first-party/fb/include/fb/fbjni/ReadableByteChannel.h b/ReactAndroid/src/main/jni/first-party/fb/include/fb/fbjni/ReadableByteChannel.h
new file mode 100644
index 000000000..f895a3e6f
--- /dev/null
+++ b/ReactAndroid/src/main/jni/first-party/fb/include/fb/fbjni/ReadableByteChannel.h
@@ -0,0 +1,23 @@
+/*
+ * Copyright (c) 2016-present, Facebook, Inc.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+#pragma once
+
+#include <fb/fbjni.h>
+#include <fb/fbjni/ByteBuffer.h>
+
+namespace facebook {
+namespace jni {
+
+class JReadableByteChannel : public JavaClass<JReadableByteChannel> {
+public:
+  static constexpr const char* kJavaDescriptor = "Ljava/nio/channels/ReadableByteChannel;";
+
+  int read(alias_ref<JByteBuffer> dest) const;
+};
+
+}}
diff --git a/ReactAndroid/src/main/jni/first-party/fb/jni/ReadableByteChannel.cpp b/ReactAndroid/src/main/jni/first-party/fb/jni/ReadableByteChannel.cpp
new file mode 100644
index 000000000..9c67df3fa
--- /dev/null
+++ b/ReactAndroid/src/main/jni/first-party/fb/jni/ReadableByteChannel.cpp
@@ -0,0 +1,21 @@
+/*
+ * Copyright (c) 2016-present, Facebook, Inc.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+#include <fb/fbjni/ReadableByteChannel.h>
+
+namespace facebook {
+namespace jni {
+
+int JReadableByteChannel::read(alias_ref<JByteBuffer> dest) const {
+  if (!self()) {
+    throwNewJavaException("java/lang/NullPointerException", "java.lang.NullPointerException");
+  }
+  static auto method = javaClassStatic()->getMethod<jint(alias_ref<JByteBuffer>)>("read");
+  return method(self(), dest);
+}
+
+}}