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diff --git a/tensorflow/examples/android/jni/object_tracking/jni_utils.h b/tensorflow/examples/android/jni/object_tracking/jni_utils.h
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+++ b/tensorflow/examples/android/jni/object_tracking/jni_utils.h
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+/* Copyright 2016 The TensorFlow Authors. All Rights Reserved.
+
+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 THIRD_PARTY_TENSORFLOW_EXAMPLES_ANDROID_JNI_OBJECT_TRACKING_JNI_UTILS_H_
+#define THIRD_PARTY_TENSORFLOW_EXAMPLES_ANDROID_JNI_OBJECT_TRACKING_JNI_UTILS_H_
+
+#include <android/log.h>
+
+#include "tensorflow/examples/android/jni/object_tracking/utils.h"
+
+// The JniIntField class is used to access Java fields from native code. This
+// technique of hiding pointers to native objects in opaque Java fields is how
+// the Android hardware libraries work. This reduces the amount of static
+// native methods and makes it easier to manage the lifetime of native objects.
+class JniIntField {
+ public:
+  JniIntField(const char* field_name) : field_name_(field_name), field_ID_(0) {}
+
+  int get(JNIEnv* env, jobject thiz) {
+    if (field_ID_ == 0) {
+      jclass cls = env->GetObjectClass(thiz);
+      CHECK_ALWAYS(cls != 0, "Unable to find class");
+      field_ID_ = env->GetFieldID(cls, field_name_,  "I");
+      CHECK_ALWAYS(field_ID_ != 0,
+          "Unable to find field %s. (Check proguard cfg)", field_name_);
+    }
+
+    return env->GetIntField(thiz, field_ID_);
+  }
+
+  void set(JNIEnv* env, jobject thiz, int value) {
+    if (field_ID_ == 0) {
+      jclass cls = env->GetObjectClass(thiz);
+      CHECK_ALWAYS(cls != 0, "Unable to find class");
+      field_ID_ = env->GetFieldID(cls, field_name_,  "I");
+      CHECK_ALWAYS(field_ID_ != 0,
+          "Unable to find field %s (Check proguard cfg)", field_name_);
+    }
+
+    env->SetIntField(thiz, field_ID_, value);
+  }
+
+ private:
+  const char* const field_name_;
+
+  // This is just a cache
+  jfieldID field_ID_;
+};
+
+#endif