From 8f09339da8bd0209dabf43a186dafb97566974cc Mon Sep 17 00:00:00 2001
From: John Firebaugh <john.firebaugh@gmail.com>
Date: Fri, 17 Aug 2018 16:25:12 -0700
Subject: [PATCH 1/4] [android] Move conversion code to .cpp files

---
 platform/android/core-files.txt               |  15 ++
 .../android/src/conversion/collection.cpp     |  38 ++++
 .../android/src/conversion/collection.hpp     |  34 +--
 platform/android/src/conversion/color.cpp     |  17 ++
 platform/android/src/conversion/color.hpp     |   8 +-
 platform/android/src/conversion/constant.cpp  |  86 ++++++++
 platform/android/src/conversion/constant.hpp  |  75 ++-----
 .../src/geojson/conversion/feature.cpp        | 192 +++++++++++++++++
 .../src/geojson/conversion/feature.hpp        | 194 +-----------------
 .../android/src/style/conversion/filter.cpp   |  26 +++
 .../android/src/style/conversion/filter.hpp   |  21 +-
 .../android/src/style/conversion/position.cpp |  24 +++
 .../android/src/style/conversion/position.hpp |  26 +--
 .../style/conversion/property_expression.hpp  |  16 +-
 .../src/style/conversion/property_value.hpp   |  16 +-
 .../style/conversion/transition_options.cpp   |  16 ++
 .../style/conversion/transition_options.hpp   |  19 +-
 .../src/style/conversion/url_or_tileset.cpp   |  30 +++
 .../src/style/conversion/url_or_tileset.hpp   |  27 +--
 19 files changed, 493 insertions(+), 387 deletions(-)
 create mode 100644 platform/android/src/conversion/collection.cpp
 create mode 100644 platform/android/src/conversion/color.cpp
 create mode 100644 platform/android/src/conversion/constant.cpp
 create mode 100644 platform/android/src/geojson/conversion/feature.cpp
 create mode 100644 platform/android/src/style/conversion/filter.cpp
 create mode 100644 platform/android/src/style/conversion/position.cpp
 create mode 100644 platform/android/src/style/conversion/transition_options.cpp
 create mode 100644 platform/android/src/style/conversion/url_or_tileset.cpp

diff --git a/platform/android/core-files.txt b/platform/android/core-files.txt
index 7d86cb5615a..ef9ec65df77 100644
--- a/platform/android/core-files.txt
+++ b/platform/android/core-files.txt
@@ -48,12 +48,27 @@ platform/default/mbgl/map/map_snapshotter.hpp
 platform/linux/src/headless_backend_egl.cpp
 
 # Conversion C++ -> Java
+platform/android/src/conversion/collection.cpp
+platform/android/src/conversion/collection.hpp
+platform/android/src/conversion/color.cpp
+platform/android/src/conversion/color.hpp
+platform/android/src/conversion/constant.cpp
 platform/android/src/conversion/constant.hpp
 platform/android/src/conversion/conversion.hpp
+platform/android/src/geojson/conversion/feature.cpp
+platform/android/src/geojson/conversion/feature.hpp
+platform/android/src/style/conversion/filter.cpp
+platform/android/src/style/conversion/filter.hpp
+platform/android/src/style/conversion/position.cpp
+platform/android/src/style/conversion/position.hpp
 platform/android/src/style/conversion/property_expression.hpp
 platform/android/src/style/conversion/property_value.hpp
+platform/android/src/style/conversion/transition_options.cpp
+platform/android/src/style/conversion/transition_options.hpp
 platform/android/src/style/conversion/types.hpp
 platform/android/src/style/conversion/types_string_values.hpp
+platform/android/src/style/conversion/url_or_tileset.cpp
+platform/android/src/style/conversion/url_or_tileset.hpp
 platform/android/src/map/camera_position.cpp
 platform/android/src/map/camera_position.hpp
 platform/android/src/map/image.cpp
diff --git a/platform/android/src/conversion/collection.cpp b/platform/android/src/conversion/collection.cpp
new file mode 100644
index 00000000000..14d817ea887
--- /dev/null
+++ b/platform/android/src/conversion/collection.cpp
@@ -0,0 +1,38 @@
+#include "collection.hpp"
+#include "constant.hpp"
+
+namespace mbgl {
+namespace android {
+namespace conversion {
+
+std::vector<std::string> toVector(JNIEnv& env, jni::jarray<jni::jobject>& array) {
+    std::vector<std::string> vector;
+    std::size_t len = jni::GetArrayLength(env, array);
+    vector.reserve(len);
+
+    for (std::size_t i = 0; i < len; i++) {
+        jni::jstring* jstr = reinterpret_cast<jni::jstring*>(jni::GetObjectArrayElement(env, array, i));
+        vector.push_back(*convert<std::string, jni::String>(env, jni::String(jstr)));
+        jni::DeleteLocalRef(env, jstr);
+    }
+
+    return vector;
+}
+
+std::vector<std::string> toVector(JNIEnv& env, jni::Array<jni::String> array) {
+    std::size_t len = array.Length(env);
+    std::vector<std::string> vector;
+    vector.reserve(len);
+
+    for (std::size_t i = 0; i < len; i++) {
+        jni::String jstr = array.Get(env, i);
+        vector.push_back(*convert<std::string, jni::String>(env, jstr));
+        jni::DeleteLocalRef(env, jstr);
+    }
+
+    return vector;
+}
+
+}
+}
+}
diff --git a/platform/android/src/conversion/collection.hpp b/platform/android/src/conversion/collection.hpp
index 2b953e73f44..973897b2129 100644
--- a/platform/android/src/conversion/collection.hpp
+++ b/platform/android/src/conversion/collection.hpp
@@ -1,9 +1,7 @@
 #pragma once
 
 #include "conversion.hpp"
-#include "constant.hpp"
 
-#include <mbgl/util/optional.hpp>
 #include <jni/jni.hpp>
 
 #include <vector>
@@ -16,7 +14,7 @@ namespace conversion {
  * Convert jarray -> ArrayList
  */
 template <class T>
-inline jni::jobject* toArrayList(JNIEnv& env, jni::jarray<T>& array) {
+jni::jobject* toArrayList(JNIEnv& env, jni::jarray<T>& array) {
     static jni::jclass* javaClass = jni::NewGlobalRef(env, &jni::FindClass(env, "java/util/Arrays")).release();
     static jni::jmethodID* asList = &jni::GetStaticMethodID(env, *javaClass, "asList", "([Ljava/lang/Object;)Ljava/util/List;");
     return reinterpret_cast<jni::jobject*>(jni::CallStaticMethod<jni::jobject*>(env, *javaClass, *asList, array));
@@ -24,34 +22,8 @@ inline jni::jobject* toArrayList(JNIEnv& env, jni::jarray<T>& array) {
 
 // Java -> C++
 
-
-inline std::vector<std::string> toVector(JNIEnv& env, jni::jarray<jni::jobject>& array) {
-    std::vector<std::string> vector;
-    std::size_t len = jni::GetArrayLength(env, array);
-    vector.reserve(len);
-
-    for (std::size_t i = 0; i < len; i++) {
-        jni::jstring* jstr = reinterpret_cast<jni::jstring*>(jni::GetObjectArrayElement(env, array, i));
-        vector.push_back(*convert<std::string, jni::String>(env, jni::String(jstr)));
-        jni::DeleteLocalRef(env, jstr);
-    }
-
-    return vector;
-}
-
-inline std::vector<std::string> toVector(JNIEnv& env, jni::Array<jni::String> array) {
-    std::size_t len = array.Length(env);
-    std::vector<std::string> vector;
-    vector.reserve(len);
-
-    for (std::size_t i = 0; i < len; i++) {
-        jni::String jstr = array.Get(env, i);
-        vector.push_back(*convert<std::string, jni::String>(env, jstr));
-        jni::DeleteLocalRef(env, jstr);
-    }
-
-    return vector;
-}
+std::vector<std::string> toVector(JNIEnv& env, jni::jarray<jni::jobject>& array);
+std::vector<std::string> toVector(JNIEnv& env, jni::Array<jni::String> array);
 
 }
 }
diff --git a/platform/android/src/conversion/color.cpp b/platform/android/src/conversion/color.cpp
new file mode 100644
index 00000000000..ce85943e61e
--- /dev/null
+++ b/platform/android/src/conversion/color.cpp
@@ -0,0 +1,17 @@
+#include "color.hpp"
+
+namespace mbgl {
+namespace android {
+namespace conversion {
+
+Result<mbgl::Color> Converter<mbgl::Color, int>::operator()(jni::JNIEnv&, const int& color) const {
+    float r = (color >> 16) & 0xFF;
+    float g = (color >> 8) & 0xFF;
+    float b = (color) & 0xFF;
+    float a = (color >> 24) & 0xFF;
+    return { mbgl::Color( r / 255.0f, g / 255.0f, b / 255.0f, a / 255.0f ) };
+}
+
+} // namespace conversion
+} // namespace style
+} // namespace mbgl
diff --git a/platform/android/src/conversion/color.hpp b/platform/android/src/conversion/color.hpp
index 40aa68d4a92..2b4144b933e 100644
--- a/platform/android/src/conversion/color.hpp
+++ b/platform/android/src/conversion/color.hpp
@@ -10,13 +10,7 @@ namespace conversion {
 
 template <>
 struct Converter<mbgl::Color, int> {
-    Result<mbgl::Color> operator()(jni::JNIEnv&, const int& color) const {
-        float r = (color >> 16) & 0xFF;
-        float g = (color >> 8) & 0xFF;
-        float b = (color) & 0xFF;
-        float a = (color >> 24) & 0xFF;
-        return { mbgl::Color( r / 255.0f, g / 255.0f, b / 255.0f, a / 255.0f ) };
-    }
+    Result<mbgl::Color> operator()(jni::JNIEnv&, const int& color) const;
 };
 
 } // namespace conversion
diff --git a/platform/android/src/conversion/constant.cpp b/platform/android/src/conversion/constant.cpp
new file mode 100644
index 00000000000..cce0796ce57
--- /dev/null
+++ b/platform/android/src/conversion/constant.cpp
@@ -0,0 +1,86 @@
+#include "constant.hpp"
+
+#include <sstream>
+
+namespace mbgl {
+namespace android {
+namespace conversion {
+
+Result<jni::jobject*> Converter<jni::jobject*, bool>::operator()(jni::JNIEnv& env, const bool& value) const {
+    static jni::jclass* javaClass = jni::NewGlobalRef(env, &jni::FindClass(env, "java/lang/Boolean")).release();
+    static jni::jmethodID* constructor = &jni::GetMethodID(env, *javaClass, "<init>", "(Z)V");
+    return {&jni::NewObject(env, *javaClass, *constructor, (jboolean) value)};
+}
+
+Result<jni::jboolean> Converter<jni::jboolean, bool>::operator()(jni::JNIEnv&, const bool& value) const {
+    return {(jni::jboolean) value};
+}
+
+Result<jni::jobject*> Converter<jni::jobject*, float>::operator()(jni::JNIEnv& env, const float& value) const {
+    static jni::jclass* javaClass = jni::NewGlobalRef(env, &jni::FindClass(env, "java/lang/Float")).release();
+    static jni::jmethodID* constructor = &jni::GetMethodID(env, *javaClass, "<init>", "(F)V");
+    return {&jni::NewObject(env, *javaClass, *constructor, (jfloat) value)};
+}
+
+Result<jni::jfloat> Converter<jni::jfloat, float>::operator()(jni::JNIEnv&, const float& value) const {
+    return {(jni::jfloat) value};
+}
+
+Result<jni::jobject*> Converter<jni::jobject*, double>::operator()(jni::JNIEnv& env, const double& value) const {
+    static jni::jclass* javaClass = jni::NewGlobalRef(env, &jni::FindClass(env, "java/lang/Double")).release();
+    static jni::jmethodID* constructor = &jni::GetMethodID(env, *javaClass, "<init>", "(D)V");
+    return {&jni::NewObject(env, *javaClass, *constructor, (jfloat) value)};
+}
+
+Result<jni::jdouble> Converter<jni::jdouble, float>::operator()(jni::JNIEnv&, const double& value) const {
+    return {(jni::jdouble) value};
+}
+
+Result<jni::jobject*> Converter<jni::jobject*, std::string>::operator()(jni::JNIEnv& env, const std::string& value) const {
+    return {jni::Make<jni::String>(env, value).Get()};
+}
+
+Result<jni::jstring*> Converter<jni::jstring*, std::string>::operator()(jni::JNIEnv& env, const std::string& value) const {
+    return {jni::Make<jni::String>(env, value).Get()};
+}
+
+Result<jni::jobject*> Converter<jni::jobject*, Color>::operator()(jni::JNIEnv& env, const Color& value) const {
+    std::stringstream sstream;
+    sstream << "rgba(" << value.r << ", " << value.g << ", " << value.b << ", "  << value.a << ")";
+    std::string result = sstream.str();
+    return convert<jni::jobject*, std::string>(env, result);
+}
+
+Result<jni::jobject*> Converter<jni::jobject*, std::vector<std::string>>::operator()(jni::JNIEnv& env, const std::vector<std::string>& value) const {
+    static jni::jclass* stringCass = jni::NewGlobalRef(env, &jni::FindClass(env, "java/lang/String")).release();
+    jni::jarray<jni::jobject>& jarray = jni::NewObjectArray(env, value.size(), *stringCass);
+
+    for(size_t i = 0; i < value.size(); i = i + 1) {
+        Result<jni::jobject*> converted = convert<jni::jobject*, std::string>(env, value.at(i));
+        jni::SetObjectArrayElement(env, jarray, i, *converted);
+    }
+
+    return &jarray;
+}
+
+Result<jni::jobject*> Converter<jni::jobject*, std::vector<float>>::operator()(jni::JNIEnv& env, const std::vector<float>& value) const {
+    static jni::jclass* floatClass = jni::NewGlobalRef(env, &jni::FindClass(env, "java/lang/Float")).release();
+    jni::jarray<jni::jobject>& jarray = jni::NewObjectArray(env, value.size(), *floatClass);
+
+    for(size_t i = 0; i < value.size(); i = i + 1) {
+        Result<jni::jobject*> converted = convert<jni::jobject*, float>(env, value.at(i));
+        jni::SetObjectArrayElement(env, jarray, i, *converted);
+    }
+
+    return &jarray;
+}
+
+// Java -> C++
+
+Result<std::string> Converter<std::string, jni::String>::operator()(jni::JNIEnv& env, const jni::String& value) const {
+    return { jni::Make<std::string>(env, value) };
+}
+
+} // namespace conversion
+} // namespace style
+} // namespace mbgl
diff --git a/platform/android/src/conversion/constant.hpp b/platform/android/src/conversion/constant.hpp
index f1c72eb5dd0..52395cb9eea 100644
--- a/platform/android/src/conversion/constant.hpp
+++ b/platform/android/src/conversion/constant.hpp
@@ -2,14 +2,12 @@
 
 #include "conversion.hpp"
 
-#include <mbgl/util/optional.hpp>
 #include <mbgl/util/color.hpp>
 #include <jni/jni.hpp>
 
 #include <string>
 #include <array>
 #include <vector>
-#include <sstream>
 
 namespace mbgl {
 namespace android {
@@ -17,51 +15,33 @@ namespace conversion {
 
 template <>
 struct Converter<jni::jobject*, bool> {
-    Result<jni::jobject*> operator()(jni::JNIEnv& env, const bool& value) const {
-        static jni::jclass* javaClass = jni::NewGlobalRef(env, &jni::FindClass(env, "java/lang/Boolean")).release();
-        static jni::jmethodID* constructor = &jni::GetMethodID(env, *javaClass, "<init>", "(Z)V");
-        return {&jni::NewObject(env, *javaClass, *constructor, (jboolean) value)};
-    }
+    Result<jni::jobject*> operator()(jni::JNIEnv& env, const bool& value) const;
 };
 
 template <>
 struct Converter<jni::jboolean, bool> {
-    Result<jni::jboolean> operator()(jni::JNIEnv&, const bool& value) const {
-        return {(jni::jboolean) value};
-    }
+    Result<jni::jboolean> operator()(jni::JNIEnv&, const bool& value) const;
 };
 
 template <>
 struct Converter<jni::jobject*, float> {
-    Result<jni::jobject*> operator()(jni::JNIEnv& env, const float& value) const {
-        static jni::jclass* javaClass = jni::NewGlobalRef(env, &jni::FindClass(env, "java/lang/Float")).release();
-        static jni::jmethodID* constructor = &jni::GetMethodID(env, *javaClass, "<init>", "(F)V");
-        return {&jni::NewObject(env, *javaClass, *constructor, (jfloat) value)};
-    }
+    Result<jni::jobject*> operator()(jni::JNIEnv& env, const float& value) const;
 };
 
 template <>
 struct Converter<jni::jfloat, float> {
-    Result<jni::jfloat> operator()(jni::JNIEnv&, const float& value) const {
-        return {(jni::jfloat) value};
-    }
+    Result<jni::jfloat> operator()(jni::JNIEnv&, const float& value) const;
 };
 
 
 template <>
 struct Converter<jni::jobject*, double> {
-    Result<jni::jobject*> operator()(jni::JNIEnv& env, const double& value) const {
-        static jni::jclass* javaClass = jni::NewGlobalRef(env, &jni::FindClass(env, "java/lang/Double")).release();
-        static jni::jmethodID* constructor = &jni::GetMethodID(env, *javaClass, "<init>", "(D)V");
-        return {&jni::NewObject(env, *javaClass, *constructor, (jfloat) value)};
-    }
+    Result<jni::jobject*> operator()(jni::JNIEnv& env, const double& value) const;
 };
 
 template <>
 struct Converter<jni::jdouble, float> {
-    Result<jni::jdouble> operator()(jni::JNIEnv&, const double& value) const {
-        return {(jni::jdouble) value};
-    }
+    Result<jni::jdouble> operator()(jni::JNIEnv&, const double& value) const;
 };
 
 /**
@@ -81,26 +61,17 @@ struct Converter<jni::jobject*, T, typename std::enable_if<std::is_integral<T>::
 
 template <>
 struct Converter<jni::jobject*, std::string> {
-    Result<jni::jobject*> operator()(jni::JNIEnv& env, const std::string& value) const {
-        return {jni::Make<jni::String>(env, value).Get()};
-    }
+    Result<jni::jobject*> operator()(jni::JNIEnv& env, const std::string& value) const;
 };
 
 template <>
 struct Converter<jni::jstring*, std::string> {
-    Result<jni::jstring*> operator()(jni::JNIEnv& env, const std::string& value) const {
-        return {jni::Make<jni::String>(env, value).Get()};
-    }
+    Result<jni::jstring*> operator()(jni::JNIEnv& env, const std::string& value) const;
 };
 
 template <>
 struct Converter<jni::jobject*, Color> {
-    Result<jni::jobject*> operator()(jni::JNIEnv& env, const Color& value) const {
-        std::stringstream sstream;
-        sstream << "rgba(" << value.r << ", " << value.g << ", " << value.b << ", "  << value.a << ")";
-        std::string result = sstream.str();
-        return convert<jni::jobject*, std::string>(env, result);
-    }
+    Result<jni::jobject*> operator()(jni::JNIEnv& env, const Color& value) const;
 };
 
 template <std::size_t N>
@@ -116,41 +87,19 @@ struct Converter<jni::jobject*, std::array<float, N>> {
 
 template <>
 struct Converter<jni::jobject*, std::vector<std::string>> {
-    Result<jni::jobject*> operator()(jni::JNIEnv& env, const std::vector<std::string>& value) const {
-        static jni::jclass* stringCass = jni::NewGlobalRef(env, &jni::FindClass(env, "java/lang/String")).release();
-        jni::jarray<jni::jobject>& jarray = jni::NewObjectArray(env, value.size(), *stringCass);
-
-        for(size_t i = 0; i < value.size(); i = i + 1) {
-            Result<jni::jobject*> converted = convert<jni::jobject*, std::string>(env, value.at(i));
-            jni::SetObjectArrayElement(env, jarray, i, *converted);
-        }
-
-        return &jarray;
-    }
+    Result<jni::jobject*> operator()(jni::JNIEnv& env, const std::vector<std::string>& value) const;
 };
 
 template <>
 struct Converter<jni::jobject*, std::vector<float>> {
-    Result<jni::jobject*> operator()(jni::JNIEnv& env, const std::vector<float>& value) const {
-        static jni::jclass* floatClass = jni::NewGlobalRef(env, &jni::FindClass(env, "java/lang/Float")).release();
-        jni::jarray<jni::jobject>& jarray = jni::NewObjectArray(env, value.size(), *floatClass);
-
-        for(size_t i = 0; i < value.size(); i = i + 1) {
-            Result<jni::jobject*> converted = convert<jni::jobject*, float>(env, value.at(i));
-            jni::SetObjectArrayElement(env, jarray, i, *converted);
-        }
-
-        return &jarray;
-    }
+    Result<jni::jobject*> operator()(jni::JNIEnv& env, const std::vector<float>& value) const;
 };
 
 // Java -> C++
 
 template <>
 struct Converter<std::string, jni::String> {
-    Result<std::string> operator()(jni::JNIEnv& env, const jni::String& value) const {
-        return { jni::Make<std::string>(env, value) };
-    }
+    Result<std::string> operator()(jni::JNIEnv& env, const jni::String& value) const;
 };
 
 } // namespace conversion
diff --git a/platform/android/src/geojson/conversion/feature.cpp b/platform/android/src/geojson/conversion/feature.cpp
new file mode 100644
index 00000000000..8dff05aa124
--- /dev/null
+++ b/platform/android/src/geojson/conversion/feature.cpp
@@ -0,0 +1,192 @@
+#include "feature.hpp"
+#include "geometry.hpp"
+
+#include "../../conversion/constant.hpp"
+#include "../../conversion/conversion.hpp"
+#include "../../jni/local_object.hpp"
+
+namespace mbgl {
+namespace android {
+namespace conversion {
+
+/**
+ * Turn feature identifier into std::string
+ */
+class FeatureIdVisitor {
+public:
+
+    template<class T>
+    std::string operator()(const T& i) const {
+        return std::to_string(i);
+    }
+
+    std::string operator()(const std::string& i) const {
+        return i;
+    }
+
+    std::string operator()(const std::nullptr_t&) const {
+        return "";
+    }
+
+};
+
+/**
+ * Turn properties into Java GSON JsonObject's
+ */
+class PropertyValueEvaluator {
+public:
+    jni::JNIEnv& env;
+
+    /**
+     * null
+     */
+    jni::jobject* operator()(const mapbox::geometry::null_value_t &) const {
+        return (jni::jobject*) nullptr;
+    }
+
+    /**
+     * Boolean primitive
+     */
+    jni::jobject* operator()(const bool& value) const {
+        static jni::jclass* javaClass = jni::NewGlobalRef(env, &jni::FindClass(env, "com/google/gson/JsonPrimitive")).release();
+        static jni::jmethodID* constructor = &jni::GetMethodID(env, *javaClass, "<init>", "(Ljava/lang/Boolean;)V");
+
+        // Create JsonPrimitive
+        jni::LocalObject<jni::jobject> converted = jni::NewLocalObject(env, *convert<jni::jobject*, bool>(env, value));
+        jni::jobject* object = &jni::NewObject(env, *javaClass, *constructor, *converted);
+
+        return object;
+    }
+
+    /**
+     * String primitive
+     */
+    jni::jobject* operator()(const std::string& value) const {
+        static jni::jclass* javaClass = jni::NewGlobalRef(env, &jni::FindClass(env, "com/google/gson/JsonPrimitive")).release();
+        static jni::jmethodID* constructor = &jni::GetMethodID(env, *javaClass, "<init>", "(Ljava/lang/String;)V");
+
+        // Create JsonPrimitive
+        jni::LocalObject<jni::jobject> converted = jni::NewLocalObject(env, *convert<jni::jobject*, std::string>(env, value));
+        jni::jobject* object = &jni::NewObject(env, *javaClass, *constructor, converted.get());
+
+        return object;
+    }
+
+    /**
+     * Number primitives
+     */
+    template <class Number>
+    jni::jobject* operator()(const Number& value) const {
+        static jni::jclass* javaClass = jni::NewGlobalRef(env, &jni::FindClass(env, "com/google/gson/JsonPrimitive")).release();
+        static jni::jmethodID* constructor = &jni::GetMethodID(env, *javaClass, "<init>", "(Ljava/lang/Number;)V");
+
+        // Create JsonPrimitive
+        jni::LocalObject<jni::jobject> converted = jni::NewLocalObject(env, *convert<jni::jobject*, Number>(env, value));
+        jni::jobject* object = &jni::NewObject(env, *javaClass, *constructor, converted.get());
+
+        return object;
+    }
+
+
+    /**
+     * Json Array
+     */
+    jni::jobject* operator()(const std::vector<mbgl::Value> &values) const {
+        static jni::jclass* javaClass = jni::NewGlobalRef(env, &jni::FindClass(env, "com/google/gson/JsonArray")).release();
+        static jni::jmethodID* constructor = &jni::GetMethodID(env, *javaClass, "<init>", "()V");;
+        static jni::jmethodID* add = &jni::GetMethodID(env, *javaClass, "add", "(Lcom/google/gson/JsonElement;)V");
+
+        // Create json array
+        jni::jobject* jarray = &jni::NewObject(env, *javaClass, *constructor);
+
+        // Add values
+        for (const auto &v : values) {
+            jni::LocalObject<jni::jobject> converted = jni::NewLocalObject(env, mbgl::Value::visit(v, *this));
+            jni::CallMethod<void>(env, jarray, *add, converted.get());
+        }
+
+        return jarray;
+    }
+
+    /**
+     * Json Object
+     */
+    jni::jobject* operator()(const std::unordered_map<std::string, mbgl::Value> &value) const {
+        // TODO: clean up duplication here
+        static jni::jclass* javaClass = jni::NewGlobalRef(env, &jni::FindClass(env, "com/google/gson/JsonObject")).release();
+        static jni::jmethodID* constructor = &jni::GetMethodID(env, *javaClass, "<init>", "()V");;
+        static jni::jmethodID* add = &jni::GetMethodID(env, *javaClass, "add", "(Ljava/lang/String;Lcom/google/gson/JsonElement;)V");
+
+        // Create json object
+        jni::jobject* jsonObject = &jni::NewObject(env, *javaClass, *constructor);
+
+        // Add items
+        for (auto &item : value) {
+            jni::LocalObject<jni::jobject> converted = jni::NewLocalObject(env, mbgl::Value::visit(item.second, *this));
+            jni::LocalObject<jni::jobject> key = jni::NewLocalObject(env, *convert<jni::jobject*, std::string>(env, item.first));
+            jni::CallMethod<void>(env, jsonObject, *add, key.get(), converted.get());
+        }
+
+        return jsonObject;
+    }
+};
+
+Result<jni::jobject*> Converter<jni::jobject*, std::unordered_map<std::string, mbgl::Value>>::operator()(jni::JNIEnv& env, const std::unordered_map<std::string, mbgl::Value>& value) const {
+    static jni::jclass* javaClass = jni::NewGlobalRef(env, &jni::FindClass(env, "com/google/gson/JsonObject")).release();
+    static jni::jmethodID* constructor = &jni::GetMethodID(env, *javaClass, "<init>", "()V");;
+    static jni::jmethodID* add = &jni::GetMethodID(env, *javaClass, "add", "(Ljava/lang/String;Lcom/google/gson/JsonElement;)V");
+
+    // Create json object
+    jni::jobject* jsonObject = &jni::NewObject(env, *javaClass, *constructor);
+
+    // Add items
+    PropertyValueEvaluator evaluator {env};
+    for (auto &item : value) {
+        jni::LocalObject<jni::jobject> converted = jni::NewLocalObject(env, mbgl::Value::visit(item.second, evaluator));
+        jni::LocalObject<jni::jobject> key = jni::NewLocalObject(env, *convert<jni::jobject*, std::string>(env, item.first));
+        jni::CallMethod<void>(env, jsonObject, *add, key.get(), converted.get());
+    }
+
+    return {jsonObject};
+}
+
+Result<jni::Object<android::geojson::Feature>> Converter<jni::Object<android::geojson::Feature>, mbgl::Feature>::operator()(jni::JNIEnv& env, const mbgl::Feature& value) const {
+
+    // Convert Id
+    FeatureIdVisitor idEvaluator;
+    std::string id = (value.id) ? mapbox::geometry::identifier::visit(value.id.value(), idEvaluator) : "";
+    auto jid = jni::Make<jni::String>(env, id);
+
+    // Convert properties
+    auto properties = jni::Object<gson::JsonObject>(*convert<jni::jobject*>(env, value.properties));
+
+    // Convert geometry
+    auto geometry = *convert<jni::Object<android::geojson::Geometry>>(env, value.geometry);
+
+    // Create feature
+    auto feature = android::geojson::Feature::fromGeometry(env, geometry, properties, jid);
+
+    //Cleanup
+    jni::DeleteLocalRef(env, jid);
+    jni::DeleteLocalRef(env, geometry);
+    jni::DeleteLocalRef(env, properties);
+
+    return feature;
+}
+
+Result<jni::Array<jni::Object<android::geojson::Feature>>> Converter<jni::Array<jni::Object<android::geojson::Feature>>, std::vector<mbgl::Feature>>::operator()(jni::JNIEnv& env, const std::vector<mbgl::Feature>& value) const {
+    using namespace mbgl::android::geojson;
+    auto features = jni::Array<jni::Object<Feature>>::New(env, value.size(), Feature::javaClass);
+
+    for(size_t i = 0; i < value.size(); i = i + 1) {
+        auto converted = *convert<jni::Object<android::geojson::Feature>, mbgl::Feature>(env, value.at(i));
+        features.Set(env, i, converted);
+        jni::DeleteLocalRef(env, converted);
+    }
+
+    return {features};
+}
+
+} // namespace conversion
+} // namespace android
+} // namespace mbgl
diff --git a/platform/android/src/geojson/conversion/feature.hpp b/platform/android/src/geojson/conversion/feature.hpp
index 8fc62a27893..031449cd234 100644
--- a/platform/android/src/geojson/conversion/feature.hpp
+++ b/platform/android/src/geojson/conversion/feature.hpp
@@ -1,215 +1,31 @@
 #pragma once
 
-#include "../../conversion/constant.hpp"
 #include "../../conversion/conversion.hpp"
-#include "geometry.hpp"
-#include "../../gson/json_object.hpp"
+#include "../feature.hpp"
 
 #include <mbgl/util/feature.hpp>
-#include <mapbox/variant.hpp>
-#include <mapbox/geometry.hpp>
-
 #include <jni/jni.hpp>
-#include "../../jni/local_object.hpp"
-#include "../feature.hpp"
 
-#include <string>
-#include <array>
 #include <vector>
-#include <sstream>
-
-#include <mbgl/util/logging.hpp>
+#include <unordered_map>
 
 namespace mbgl {
 namespace android {
 namespace conversion {
 
-/**
- * Turn feature identifier into std::string
- */
-class FeatureIdVisitor {
-public:
-
-    template<class T>
-    std::string operator()(const T& i) const {
-        return std::to_string(i);
-    }
-
-    std::string operator()(const std::string& i) const {
-        return i;
-    }
-
-    std::string operator()(const std::nullptr_t&) const {
-        return "";
-    }
-
-};
-
-/**
- * Turn properties into Java GSON JsonObject's
- */
-class PropertyValueEvaluator {
-public:
-    jni::JNIEnv& env;
-
-    /**
-     * null
-     */
-    jni::jobject* operator()(const mapbox::geometry::null_value_t &) const {
-        return (jni::jobject*) nullptr;
-    }
-
-    /**
-     * Boolean primitive
-     */
-    jni::jobject* operator()(const bool& value) const {
-        static jni::jclass* javaClass = jni::NewGlobalRef(env, &jni::FindClass(env, "com/google/gson/JsonPrimitive")).release();
-        static jni::jmethodID* constructor = &jni::GetMethodID(env, *javaClass, "<init>", "(Ljava/lang/Boolean;)V");
-
-        // Create JsonPrimitive
-        jni::LocalObject<jni::jobject> converted = jni::NewLocalObject(env, *convert<jni::jobject*, bool>(env, value));
-        jni::jobject* object = &jni::NewObject(env, *javaClass, *constructor, *converted);
-
-        return object;
-    }
-
-    /**
-     * String primitive
-     */
-    jni::jobject* operator()(const std::string& value) const {
-        static jni::jclass* javaClass = jni::NewGlobalRef(env, &jni::FindClass(env, "com/google/gson/JsonPrimitive")).release();
-        static jni::jmethodID* constructor = &jni::GetMethodID(env, *javaClass, "<init>", "(Ljava/lang/String;)V");
-
-        // Create JsonPrimitive
-        jni::LocalObject<jni::jobject> converted = jni::NewLocalObject(env, *convert<jni::jobject*, std::string>(env, value));
-        jni::jobject* object = &jni::NewObject(env, *javaClass, *constructor, converted.get());
-
-        return object;
-    }
-
-    /**
-     * Number primitives
-     */
-    template <class Number>
-    jni::jobject* operator()(const Number& value) const {
-        static jni::jclass* javaClass = jni::NewGlobalRef(env, &jni::FindClass(env, "com/google/gson/JsonPrimitive")).release();
-        static jni::jmethodID* constructor = &jni::GetMethodID(env, *javaClass, "<init>", "(Ljava/lang/Number;)V");
-
-        // Create JsonPrimitive
-        jni::LocalObject<jni::jobject> converted = jni::NewLocalObject(env, *convert<jni::jobject*, Number>(env, value));
-        jni::jobject* object = &jni::NewObject(env, *javaClass, *constructor, converted.get());
-
-        return object;
-    }
-
-
-    /**
-     * Json Array
-     */
-    jni::jobject* operator()(const std::vector<mbgl::Value> &values) const {
-        static jni::jclass* javaClass = jni::NewGlobalRef(env, &jni::FindClass(env, "com/google/gson/JsonArray")).release();
-        static jni::jmethodID* constructor = &jni::GetMethodID(env, *javaClass, "<init>", "()V");;
-        static jni::jmethodID* add = &jni::GetMethodID(env, *javaClass, "add", "(Lcom/google/gson/JsonElement;)V");
-
-        // Create json array
-        jni::jobject* jarray = &jni::NewObject(env, *javaClass, *constructor);
-
-        // Add values
-        for (const auto &v : values) {
-            jni::LocalObject<jni::jobject> converted = jni::NewLocalObject(env, mbgl::Value::visit(v, *this));
-            jni::CallMethod<void>(env, jarray, *add, converted.get());
-        }
-
-        return jarray;
-    }
-
-    /**
-     * Json Object
-     */
-    jni::jobject* operator()(const std::unordered_map<std::string, mbgl::Value> &value) const {
-        // TODO: clean up duplication here
-        static jni::jclass* javaClass = jni::NewGlobalRef(env, &jni::FindClass(env, "com/google/gson/JsonObject")).release();
-        static jni::jmethodID* constructor = &jni::GetMethodID(env, *javaClass, "<init>", "()V");;
-        static jni::jmethodID* add = &jni::GetMethodID(env, *javaClass, "add", "(Ljava/lang/String;Lcom/google/gson/JsonElement;)V");
-
-        // Create json object
-        jni::jobject* jsonObject = &jni::NewObject(env, *javaClass, *constructor);
-
-        // Add items
-        for (auto &item : value) {
-            jni::LocalObject<jni::jobject> converted = jni::NewLocalObject(env, mbgl::Value::visit(item.second, *this));
-            jni::LocalObject<jni::jobject> key = jni::NewLocalObject(env, *convert<jni::jobject*, std::string>(env, item.first));
-            jni::CallMethod<void>(env, jsonObject, *add, key.get(), converted.get());
-        }
-
-        return jsonObject;
-    }
-};
-
 template <>
 struct Converter<jni::jobject*, std::unordered_map<std::string, mbgl::Value>> {
-    Result<jni::jobject*> operator()(jni::JNIEnv& env, const std::unordered_map<std::string, mbgl::Value>& value) const {
-        static jni::jclass* javaClass = jni::NewGlobalRef(env, &jni::FindClass(env, "com/google/gson/JsonObject")).release();
-        static jni::jmethodID* constructor = &jni::GetMethodID(env, *javaClass, "<init>", "()V");;
-        static jni::jmethodID* add = &jni::GetMethodID(env, *javaClass, "add", "(Ljava/lang/String;Lcom/google/gson/JsonElement;)V");
-
-        // Create json object
-        jni::jobject* jsonObject = &jni::NewObject(env, *javaClass, *constructor);
-
-        // Add items
-        PropertyValueEvaluator evaluator {env};
-        for (auto &item : value) {
-            jni::LocalObject<jni::jobject> converted = jni::NewLocalObject(env, mbgl::Value::visit(item.second, evaluator));
-            jni::LocalObject<jni::jobject> key = jni::NewLocalObject(env, *convert<jni::jobject*, std::string>(env, item.first));
-            jni::CallMethod<void>(env, jsonObject, *add, key.get(), converted.get());
-        }
-
-        return {jsonObject};
-    }
+    Result<jni::jobject*> operator()(jni::JNIEnv& env, const std::unordered_map<std::string, mbgl::Value>& value) const;
 };
 
-
 template <>
 struct Converter<jni::Object<android::geojson::Feature>, mbgl::Feature> {
-    Result<jni::Object<android::geojson::Feature>> operator()(jni::JNIEnv& env, const mbgl::Feature& value) const {
-
-        // Convert Id
-        FeatureIdVisitor idEvaluator;
-        std::string id = (value.id) ? mapbox::geometry::identifier::visit(value.id.value(), idEvaluator) : "";
-        auto jid = jni::Make<jni::String>(env, id);
-
-        // Convert properties
-        auto properties = jni::Object<gson::JsonObject>(*convert<jni::jobject*>(env, value.properties));
-
-        // Convert geometry
-        auto geometry = *convert<jni::Object<android::geojson::Geometry>>(env, value.geometry);
-
-        // Create feature
-        auto feature = android::geojson::Feature::fromGeometry(env, geometry, properties, jid);
-
-        //Cleanup
-        jni::DeleteLocalRef(env, jid);
-        jni::DeleteLocalRef(env, geometry);
-        jni::DeleteLocalRef(env, properties);
-
-        return feature;
-    }
+    Result<jni::Object<android::geojson::Feature>> operator()(jni::JNIEnv& env, const mbgl::Feature& value) const;
 };
 
 template <>
 struct Converter<jni::Array<jni::Object<android::geojson::Feature>>, std::vector<mbgl::Feature>> {
-    Result<jni::Array<jni::Object<android::geojson::Feature>>> operator()(jni::JNIEnv& env, const std::vector<mbgl::Feature>& value) const {
-        using namespace mbgl::android::geojson;
-        auto features = jni::Array<jni::Object<Feature>>::New(env, value.size(), Feature::javaClass);
-
-        for(size_t i = 0; i < value.size(); i = i + 1) {
-            auto converted = *convert<jni::Object<android::geojson::Feature>, mbgl::Feature>(env, value.at(i));
-            features.Set(env, i, converted);
-            jni::DeleteLocalRef(env, converted);
-        }
-
-        return {features};
-    }
+    Result<jni::Array<jni::Object<android::geojson::Feature>>> operator()(jni::JNIEnv& env, const std::vector<mbgl::Feature>& value) const;
 };
 
 } // namespace conversion
diff --git a/platform/android/src/style/conversion/filter.cpp b/platform/android/src/style/conversion/filter.cpp
new file mode 100644
index 00000000000..4eac0cf82b2
--- /dev/null
+++ b/platform/android/src/style/conversion/filter.cpp
@@ -0,0 +1,26 @@
+#include "filter.hpp"
+#include "../android_conversion.hpp"
+
+#include <mbgl/style/conversion.hpp>
+#include <mbgl/style/conversion/filter.hpp>
+
+namespace mbgl {
+namespace android {
+namespace conversion {
+
+optional<mbgl::style::Filter> toFilter(jni::JNIEnv& env, jni::Array<jni::Object<>> jfilter) {
+    mbgl::optional<mbgl::style::Filter> filter;
+    if (jfilter) {
+      mbgl::style::conversion::Error error;
+      auto converted = mbgl::style::conversion::convert<mbgl::style::Filter>(Value(env, jfilter), error);
+      if (!converted) {
+          mbgl::Log::Error(mbgl::Event::JNI, "Error converting filter: " + error.message);
+      }
+      filter = std::move(*converted);
+    }
+    return filter;
+}
+
+} // namespace conversion
+} // namespace android
+} // namespace mbgl
\ No newline at end of file
diff --git a/platform/android/src/style/conversion/filter.hpp b/platform/android/src/style/conversion/filter.hpp
index 241c98713ac..df482de8f3c 100644
--- a/platform/android/src/style/conversion/filter.hpp
+++ b/platform/android/src/style/conversion/filter.hpp
@@ -1,30 +1,15 @@
 #pragma once
 
-#include "../android_conversion.hpp"
-#include <mbgl/style/conversion/filter.hpp>
-#include <mbgl/style/conversion_impl.hpp>
+#include <mbgl/style/filter.hpp>
+#include <mbgl/util/optional.hpp>
 
 #include <jni/jni.hpp>
 
-#include <tuple>
-#include <map>
-
 namespace mbgl {
 namespace android {
 namespace conversion {
 
-inline optional<mbgl::style::Filter> toFilter(jni::JNIEnv& env, jni::Array<jni::Object<>> jfilter) {
-    mbgl::optional<mbgl::style::Filter> filter;
-    if (jfilter) {
-      mbgl::style::conversion::Error error;
-      auto converted = mbgl::style::conversion::convert<mbgl::style::Filter>(Value(env, jfilter), error);
-      if (!converted) {
-          mbgl::Log::Error(mbgl::Event::JNI, "Error converting filter: " + error.message);
-      }
-      filter = std::move(*converted);
-    }
-    return filter;
-}
+optional<mbgl::style::Filter> toFilter(jni::JNIEnv&, jni::Array<jni::Object<>>);
 
 } // namespace conversion
 } // namespace android
diff --git a/platform/android/src/style/conversion/position.cpp b/platform/android/src/style/conversion/position.cpp
new file mode 100644
index 00000000000..9b3925914e0
--- /dev/null
+++ b/platform/android/src/style/conversion/position.cpp
@@ -0,0 +1,24 @@
+#include "position.hpp"
+
+namespace mbgl {
+namespace android {
+namespace conversion {
+
+Result<jni::Object<Position>> Converter<jni::Object<Position>, mbgl::style::Position>::operator()(jni::JNIEnv &env, const mbgl::style::Position &value) const {
+    std::array<float, 3> cartPosition = value.getSpherical();
+    return Position::fromPosition(env, cartPosition[0], cartPosition[1], cartPosition[2]);
+}
+
+Result<mbgl::style::Position> Converter<mbgl::style::Position, jni::Object<Position>>::operator()(jni::JNIEnv &env, const jni::Object<Position> &value) const {
+    float radialCoordinate = Position::getRadialCoordinate(env, value);
+    float azimuthalAngle = Position::getAzimuthalAngle(env, value);
+    float polarAngle = Position::getPolarAngle(env, value);
+    std::array<float, 3> cartPosition {{radialCoordinate, azimuthalAngle, polarAngle}};
+    mbgl::style::Position position{};
+    position.set(cartPosition);
+    return position;
+}
+
+}
+}
+}
diff --git a/platform/android/src/style/conversion/position.hpp b/platform/android/src/style/conversion/position.hpp
index f32a892c0ca..2ef4bf43955 100644
--- a/platform/android/src/style/conversion/position.hpp
+++ b/platform/android/src/style/conversion/position.hpp
@@ -1,37 +1,25 @@
 #pragma once
 
 #include "../../conversion/conversion.hpp"
+#include "../position.hpp"
 
-#include <jni/jni.hpp>
 #include <mbgl/style/position.hpp>
-#include "../../jni/local_object.hpp"
-#include "../position.hpp"
+#include <jni/jni.hpp>
 
 namespace mbgl {
 namespace android {
 namespace conversion {
 
-template<>
+template <>
 struct Converter<jni::Object<Position>, mbgl::style::Position> {
-    Result<jni::Object<Position>> operator()(jni::JNIEnv &env, const mbgl::style::Position &value) const {
-        std::array<float, 3> cartPosition = value.getSpherical();
-        return Position::fromPosition(env, cartPosition[0], cartPosition[1], cartPosition[2]);
-    }
+    Result<jni::Object<Position>> operator()(jni::JNIEnv &env, const mbgl::style::Position &value) const;
 };
 
-template<>
+template <>
 struct Converter<mbgl::style::Position, jni::Object<Position>> {
-    Result<mbgl::style::Position> operator()(jni::JNIEnv &env, const jni::Object<Position> &value) const {
-        float radialCoordinate = Position::getRadialCoordinate(env, value);
-        float azimuthalAngle = Position::getAzimuthalAngle(env, value);
-        float polarAngle = Position::getPolarAngle(env, value);
-        std::array<float, 3> cartPosition {{radialCoordinate, azimuthalAngle, polarAngle}};
-        mbgl::style::Position position{};
-        position.set(cartPosition);
-        return position;
-    }
+    Result<mbgl::style::Position> operator()(jni::JNIEnv &env, const jni::Object<Position> &value) const;
 };
 
 }
 }
-}
\ No newline at end of file
+}
diff --git a/platform/android/src/style/conversion/property_expression.hpp b/platform/android/src/style/conversion/property_expression.hpp
index ae9d4ea41c4..08429960cb6 100644
--- a/platform/android/src/style/conversion/property_expression.hpp
+++ b/platform/android/src/style/conversion/property_expression.hpp
@@ -1,16 +1,11 @@
 #pragma once
 
-#include <mbgl/style/property_value.hpp>
 #include "../../conversion/conversion.hpp"
-#include "../../conversion/constant.hpp"
-#include "types.hpp"
-#include "../../java/lang.hpp"
-
-#include <jni/jni.hpp>
 #include "../../gson/json_element.hpp"
 
-#include <tuple>
-#include <map>
+#include <mbgl/style/property_expression.hpp>
+
+#include <jni/jni.hpp>
 
 namespace mbgl {
 namespace android {
@@ -18,11 +13,8 @@ namespace conversion {
 
 template <class T>
 struct Converter<jni::Object<android::gson::JsonElement>, mbgl::style::PropertyExpression<T>> {
-
     Result<jni::Object<android::gson::JsonElement>> operator()(jni::JNIEnv& env, const mbgl::style::PropertyExpression<T>& value) const {
-        // Convert expressions
-        mbgl::Value expressionValue = value.getExpression().serialize();
-        return gson::JsonElement::New(env, expressionValue);
+        return gson::JsonElement::New(env, value.getExpression().serialize());
     }
 };
 
diff --git a/platform/android/src/style/conversion/property_value.hpp b/platform/android/src/style/conversion/property_value.hpp
index 256647cddf0..e4d8f59ec3f 100644
--- a/platform/android/src/style/conversion/property_value.hpp
+++ b/platform/android/src/style/conversion/property_value.hpp
@@ -2,6 +2,7 @@
 
 #include <mbgl/style/color_ramp_property_value.hpp>
 #include <mbgl/style/property_value.hpp>
+
 #include "../../conversion/conversion.hpp"
 #include "../../conversion/constant.hpp"
 #include "property_expression.hpp"
@@ -17,25 +18,22 @@ namespace conversion {
 template <typename T>
 class PropertyValueEvaluator {
 public:
-
     PropertyValueEvaluator(jni::JNIEnv& _env) : env(_env) {}
 
     jni::jobject* operator()(const mbgl::style::Undefined) const {
         return nullptr;
     }
 
-    jni::jobject* operator()(const T &value) const {
-        Result<jni::jobject*> result = convert<jni::jobject*>(env, value);
-        return *result;
+    jni::jobject* operator()(const T& value) const {
+        return *convert<jni::jobject*>(env, value);
     }
 
-    jni::jobject* operator()(const mbgl::style::PropertyExpression<T> &value) const {
-        return *convert<jni::Object<android::gson::JsonElement>, mbgl::style::PropertyExpression<T>>(env, value);
+    jni::jobject* operator()(const mbgl::style::PropertyExpression<T>& value) const {
+        return *convert<jni::Object<android::gson::JsonElement>>(env, value);
     }
 
 private:
     jni::JNIEnv& env;
-
 };
 
 /**
@@ -43,7 +41,6 @@ class PropertyValueEvaluator {
  */
 template <class T>
 struct Converter<jni::jobject*, mbgl::style::PropertyValue<T>> {
-
     Result<jni::jobject*> operator()(jni::JNIEnv& env, const mbgl::style::PropertyValue<T>& value) const {
         PropertyValueEvaluator<T> evaluator(env);
         return value.evaluate(evaluator);
@@ -55,8 +52,7 @@ struct Converter<jni::jobject*, mbgl::style::PropertyValue<T>> {
  */
 template <>
 struct Converter<jni::jobject*, mbgl::style::ColorRampPropertyValue> {
-
-    Result<jni::jobject*> operator()(jni::JNIEnv& env, const mbgl::style::ColorRampPropertyValue value) const {
+    Result<jni::jobject*> operator()(jni::JNIEnv& env, const mbgl::style::ColorRampPropertyValue& value) const {
         PropertyValueEvaluator<mbgl::style::ColorRampPropertyValue> evaluator(env);
         return *convert<jni::jobject*>(env, value.evaluate(evaluator));
     }
diff --git a/platform/android/src/style/conversion/transition_options.cpp b/platform/android/src/style/conversion/transition_options.cpp
new file mode 100644
index 00000000000..313333ad17e
--- /dev/null
+++ b/platform/android/src/style/conversion/transition_options.cpp
@@ -0,0 +1,16 @@
+#include "transition_options.hpp"
+
+namespace mbgl {
+namespace android {
+namespace conversion {
+
+Result<jni::Object<TransitionOptions>> Converter<jni::Object<TransitionOptions>, mbgl::style::TransitionOptions>::operator()(jni::JNIEnv& env, const mbgl::style::TransitionOptions& value) const {
+    return TransitionOptions::fromTransitionOptions(env,
+        std::chrono::duration_cast<std::chrono::milliseconds>(value.duration.value_or(mbgl::Duration::zero())).count(),
+        std::chrono::duration_cast<std::chrono::milliseconds>(value.delay.value_or(mbgl::Duration::zero())).count()
+    );
+}
+
+}
+}
+}
diff --git a/platform/android/src/style/conversion/transition_options.hpp b/platform/android/src/style/conversion/transition_options.hpp
index ae65a32194a..6630456d37a 100644
--- a/platform/android/src/style/conversion/transition_options.hpp
+++ b/platform/android/src/style/conversion/transition_options.hpp
@@ -1,11 +1,11 @@
 #pragma once
 
 #include "../../conversion/conversion.hpp"
+#include "../transition_options.hpp"
 
-#include <jni/jni.hpp>
 #include <mbgl/style/transition_options.hpp>
-#include "../../jni/local_object.hpp"
-#include "../transition_options.hpp"
+
+#include <jni/jni.hpp>
 
 namespace mbgl {
 namespace android {
@@ -13,18 +13,9 @@ namespace conversion {
 
 template<>
 struct Converter<jni::Object<TransitionOptions>, mbgl::style::TransitionOptions> {
-    Result<jni::Object<TransitionOptions>> operator()(jni::JNIEnv &env, const mbgl::style::TransitionOptions &value) const {
-
-        // Convert duration
-        jlong duration =  std::chrono::duration_cast<std::chrono::milliseconds>(value.duration.value_or(mbgl::Duration::zero())).count();
-        // Convert delay
-        jlong delay = std::chrono::duration_cast<std::chrono::milliseconds>(value.delay.value_or(mbgl::Duration::zero())).count();
-
-        // Create transition options
-        return TransitionOptions::fromTransitionOptions(env, duration, delay);
-    }
+    Result<jni::Object<TransitionOptions>> operator()(jni::JNIEnv&, const mbgl::style::TransitionOptions&) const;
 };
 
 }
 }
-}
\ No newline at end of file
+}
diff --git a/platform/android/src/style/conversion/url_or_tileset.cpp b/platform/android/src/style/conversion/url_or_tileset.cpp
new file mode 100644
index 00000000000..2ec58567515
--- /dev/null
+++ b/platform/android/src/style/conversion/url_or_tileset.cpp
@@ -0,0 +1,30 @@
+#include "url_or_tileset.hpp"
+#include "../android_conversion.hpp"
+
+#include <mbgl/style/conversion.hpp>
+#include <mbgl/style/conversion/tileset.hpp>
+
+namespace mbgl {
+namespace android {
+
+// This conversion is expected not to fail because it's used only in contexts where
+// the value was originally a String or TileSet object on the Java side. If it fails
+// to convert, it's a bug in our serialization or Java-side static typing.
+variant<std::string, Tileset> convertURLOrTileset(mbgl::android::Value&& value) {
+    using namespace mbgl::style::conversion;
+
+    const Convertible convertible(std::move(value));
+    if (isObject(convertible)) {
+        Error error;
+        optional<Tileset> tileset = convert<Tileset>(convertible, error);
+        if (!tileset) {
+            throw std::logic_error(error.message);
+        }
+        return { *tileset };
+    } else {
+        return { *toString(convertible) };
+    }
+}
+
+}
+}
diff --git a/platform/android/src/style/conversion/url_or_tileset.hpp b/platform/android/src/style/conversion/url_or_tileset.hpp
index d6bf86639cd..f42a9b9a2a9 100644
--- a/platform/android/src/style/conversion/url_or_tileset.hpp
+++ b/platform/android/src/style/conversion/url_or_tileset.hpp
@@ -1,37 +1,16 @@
 #pragma once
 
-#include <mbgl/util/optional.hpp>
 #include <mbgl/util/variant.hpp>
-
 #include <mbgl/util/tileset.hpp>
-#include <mbgl/style/conversion/tileset.hpp>
-#include <mbgl/style/conversion_impl.hpp>
-
-#include <jni/jni.hpp>
 
 #include <string>
 
+#include "../value.hpp"
+
 namespace mbgl {
 namespace android {
 
-// This conversion is expected not to fail because it's used only in contexts where
-// the value was originally a String or TileSet object on the Java side. If it fails
-// to convert, it's a bug in our serialization or Java-side static typing.
-inline variant<std::string, Tileset> convertURLOrTileset(mbgl::android::Value&& value) {
-    using namespace mbgl::style::conversion;
-
-    const Convertible convertible(std::move(value));
-    if (isObject(convertible)) {
-        Error error;
-        optional<Tileset> tileset = convert<Tileset>(convertible, error);
-        if (!tileset) {
-            throw std::logic_error(error.message);
-        }
-        return { *tileset };
-    } else {
-        return { *toString(convertible) };
-    }
-}
+variant<std::string, Tileset> convertURLOrTileset(mbgl::android::Value&& value);
 
 }
 }

From 14698650151d7d95d64c426f7e055f94f9cb2d40 Mon Sep 17 00:00:00 2001
From: John Firebaugh <john.firebaugh@gmail.com>
Date: Fri, 17 Aug 2018 17:04:20 -0700
Subject: [PATCH 2/4] [android] Remove unused

---
 .../android/src/conversion/collection.cpp     | 14 -----------
 .../android/src/conversion/collection.hpp     | 13 ----------
 platform/android/src/conversion/constant.cpp  | 16 -------------
 platform/android/src/conversion/constant.hpp  | 21 ----------------
 .../src/style/conversion/latlngquad.hpp       | 24 -------------------
 5 files changed, 88 deletions(-)
 delete mode 100644 platform/android/src/style/conversion/latlngquad.hpp

diff --git a/platform/android/src/conversion/collection.cpp b/platform/android/src/conversion/collection.cpp
index 14d817ea887..27b614e8cdd 100644
--- a/platform/android/src/conversion/collection.cpp
+++ b/platform/android/src/conversion/collection.cpp
@@ -5,20 +5,6 @@ namespace mbgl {
 namespace android {
 namespace conversion {
 
-std::vector<std::string> toVector(JNIEnv& env, jni::jarray<jni::jobject>& array) {
-    std::vector<std::string> vector;
-    std::size_t len = jni::GetArrayLength(env, array);
-    vector.reserve(len);
-
-    for (std::size_t i = 0; i < len; i++) {
-        jni::jstring* jstr = reinterpret_cast<jni::jstring*>(jni::GetObjectArrayElement(env, array, i));
-        vector.push_back(*convert<std::string, jni::String>(env, jni::String(jstr)));
-        jni::DeleteLocalRef(env, jstr);
-    }
-
-    return vector;
-}
-
 std::vector<std::string> toVector(JNIEnv& env, jni::Array<jni::String> array) {
     std::size_t len = array.Length(env);
     std::vector<std::string> vector;
diff --git a/platform/android/src/conversion/collection.hpp b/platform/android/src/conversion/collection.hpp
index 973897b2129..bb8941c984f 100644
--- a/platform/android/src/conversion/collection.hpp
+++ b/platform/android/src/conversion/collection.hpp
@@ -10,19 +10,6 @@ namespace mbgl {
 namespace android {
 namespace conversion {
 
-/**
- * Convert jarray -> ArrayList
- */
-template <class T>
-jni::jobject* toArrayList(JNIEnv& env, jni::jarray<T>& array) {
-    static jni::jclass* javaClass = jni::NewGlobalRef(env, &jni::FindClass(env, "java/util/Arrays")).release();
-    static jni::jmethodID* asList = &jni::GetStaticMethodID(env, *javaClass, "asList", "([Ljava/lang/Object;)Ljava/util/List;");
-    return reinterpret_cast<jni::jobject*>(jni::CallStaticMethod<jni::jobject*>(env, *javaClass, *asList, array));
-}
-
-// Java -> C++
-
-std::vector<std::string> toVector(JNIEnv& env, jni::jarray<jni::jobject>& array);
 std::vector<std::string> toVector(JNIEnv& env, jni::Array<jni::String> array);
 
 }
diff --git a/platform/android/src/conversion/constant.cpp b/platform/android/src/conversion/constant.cpp
index cce0796ce57..16e8b329438 100644
--- a/platform/android/src/conversion/constant.cpp
+++ b/platform/android/src/conversion/constant.cpp
@@ -12,38 +12,22 @@ Result<jni::jobject*> Converter<jni::jobject*, bool>::operator()(jni::JNIEnv& en
     return {&jni::NewObject(env, *javaClass, *constructor, (jboolean) value)};
 }
 
-Result<jni::jboolean> Converter<jni::jboolean, bool>::operator()(jni::JNIEnv&, const bool& value) const {
-    return {(jni::jboolean) value};
-}
-
 Result<jni::jobject*> Converter<jni::jobject*, float>::operator()(jni::JNIEnv& env, const float& value) const {
     static jni::jclass* javaClass = jni::NewGlobalRef(env, &jni::FindClass(env, "java/lang/Float")).release();
     static jni::jmethodID* constructor = &jni::GetMethodID(env, *javaClass, "<init>", "(F)V");
     return {&jni::NewObject(env, *javaClass, *constructor, (jfloat) value)};
 }
 
-Result<jni::jfloat> Converter<jni::jfloat, float>::operator()(jni::JNIEnv&, const float& value) const {
-    return {(jni::jfloat) value};
-}
-
 Result<jni::jobject*> Converter<jni::jobject*, double>::operator()(jni::JNIEnv& env, const double& value) const {
     static jni::jclass* javaClass = jni::NewGlobalRef(env, &jni::FindClass(env, "java/lang/Double")).release();
     static jni::jmethodID* constructor = &jni::GetMethodID(env, *javaClass, "<init>", "(D)V");
     return {&jni::NewObject(env, *javaClass, *constructor, (jfloat) value)};
 }
 
-Result<jni::jdouble> Converter<jni::jdouble, float>::operator()(jni::JNIEnv&, const double& value) const {
-    return {(jni::jdouble) value};
-}
-
 Result<jni::jobject*> Converter<jni::jobject*, std::string>::operator()(jni::JNIEnv& env, const std::string& value) const {
     return {jni::Make<jni::String>(env, value).Get()};
 }
 
-Result<jni::jstring*> Converter<jni::jstring*, std::string>::operator()(jni::JNIEnv& env, const std::string& value) const {
-    return {jni::Make<jni::String>(env, value).Get()};
-}
-
 Result<jni::jobject*> Converter<jni::jobject*, Color>::operator()(jni::JNIEnv& env, const Color& value) const {
     std::stringstream sstream;
     sstream << "rgba(" << value.r << ", " << value.g << ", " << value.b << ", "  << value.a << ")";
diff --git a/platform/android/src/conversion/constant.hpp b/platform/android/src/conversion/constant.hpp
index 52395cb9eea..a0675479552 100644
--- a/platform/android/src/conversion/constant.hpp
+++ b/platform/android/src/conversion/constant.hpp
@@ -18,32 +18,16 @@ struct Converter<jni::jobject*, bool> {
     Result<jni::jobject*> operator()(jni::JNIEnv& env, const bool& value) const;
 };
 
-template <>
-struct Converter<jni::jboolean, bool> {
-    Result<jni::jboolean> operator()(jni::JNIEnv&, const bool& value) const;
-};
-
 template <>
 struct Converter<jni::jobject*, float> {
     Result<jni::jobject*> operator()(jni::JNIEnv& env, const float& value) const;
 };
 
-template <>
-struct Converter<jni::jfloat, float> {
-    Result<jni::jfloat> operator()(jni::JNIEnv&, const float& value) const;
-};
-
-
 template <>
 struct Converter<jni::jobject*, double> {
     Result<jni::jobject*> operator()(jni::JNIEnv& env, const double& value) const;
 };
 
-template <>
-struct Converter<jni::jdouble, float> {
-    Result<jni::jdouble> operator()(jni::JNIEnv&, const double& value) const;
-};
-
 /**
  * All integrals. java is limited to 64 bit signed, so...
  * TODO: use BigDecimal for > 64 / unsigned?
@@ -64,11 +48,6 @@ struct Converter<jni::jobject*, std::string> {
     Result<jni::jobject*> operator()(jni::JNIEnv& env, const std::string& value) const;
 };
 
-template <>
-struct Converter<jni::jstring*, std::string> {
-    Result<jni::jstring*> operator()(jni::JNIEnv& env, const std::string& value) const;
-};
-
 template <>
 struct Converter<jni::jobject*, Color> {
     Result<jni::jobject*> operator()(jni::JNIEnv& env, const Color& value) const;
diff --git a/platform/android/src/style/conversion/latlngquad.hpp b/platform/android/src/style/conversion/latlngquad.hpp
deleted file mode 100644
index 95883368554..00000000000
--- a/platform/android/src/style/conversion/latlngquad.hpp
+++ /dev/null
@@ -1,24 +0,0 @@
-#pragma once
-
-#include <mapbox/geojson.hpp>
-#include <mbgl/style/conversion/geojson.hpp>
-#include <mbgl/style/conversion_impl.hpp>
-#include <jni/jni.hpp>
-
-namespace mbgl {
-namespace style {
-namespace conversion {
-
-template <>
-optional<std::array<LatLng, 4>> Converter<std::array<LatLng, 4>>::operator()(const mbgl::android::Value& value, Error& error) const {
-    if (value.isNull() || !value.isArray()) {
-        error = { "value cannot be converted to LatLng array" };
-        return {};
-    }
-
-    return convert<GeoJSON>(value.toString(), error);
-}
-
-} // namespace conversion
-} // namespace style
-} // namespace mbgl

From 0a74a3a5ce9506f71faa0e34843b109f48f431b0 Mon Sep 17 00:00:00 2001
From: John Firebaugh <john.firebaugh@gmail.com>
Date: Fri, 17 Aug 2018 18:05:15 -0700
Subject: [PATCH 3/4] [android] Simplify enum conversion

---
 platform/android/core-files.txt               |   2 -
 .../android/scripts/generate-style-code.js    |  17 --
 platform/android/src/conversion/constant.hpp  |   9 +
 .../src/style/conversion/property_value.hpp   |   1 -
 .../android/src/style/conversion/types.hpp    | 119 --------
 .../src/style/conversion/types.hpp.ejs        |  40 ---
 .../style/conversion/types_string_values.hpp  | 257 ------------------
 .../conversion/types_string_values.hpp.ejs    |  48 ----
 8 files changed, 9 insertions(+), 484 deletions(-)
 delete mode 100644 platform/android/src/style/conversion/types.hpp
 delete mode 100644 platform/android/src/style/conversion/types.hpp.ejs
 delete mode 100644 platform/android/src/style/conversion/types_string_values.hpp
 delete mode 100644 platform/android/src/style/conversion/types_string_values.hpp.ejs

diff --git a/platform/android/core-files.txt b/platform/android/core-files.txt
index ef9ec65df77..cdcffb857fe 100644
--- a/platform/android/core-files.txt
+++ b/platform/android/core-files.txt
@@ -65,8 +65,6 @@ platform/android/src/style/conversion/property_expression.hpp
 platform/android/src/style/conversion/property_value.hpp
 platform/android/src/style/conversion/transition_options.cpp
 platform/android/src/style/conversion/transition_options.hpp
-platform/android/src/style/conversion/types.hpp
-platform/android/src/style/conversion/types_string_values.hpp
 platform/android/src/style/conversion/url_or_tileset.cpp
 platform/android/src/style/conversion/url_or_tileset.hpp
 platform/android/src/map/camera_position.cpp
diff --git a/platform/android/scripts/generate-style-code.js b/platform/android/scripts/generate-style-code.js
index 888b9fca30c..98c5a446b9d 100755
--- a/platform/android/scripts/generate-style-code.js
+++ b/platform/android/scripts/generate-style-code.js
@@ -363,20 +363,3 @@ writeIfModified(
     `platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/style/layers/Property.java`,
     enumPropertyJavaTemplate({properties: enumProperties})
 );
-
-// De-duplicate enum properties before processing jni property templates
-const enumPropertiesDeDup = _(enumProperties).uniqBy(global.propertyNativeType).value();
-
-// JNI Enum property conversion templates
-const enumPropertyHppTypeStringValueTemplate = ejs.compile(fs.readFileSync('platform/android/src/style/conversion/types_string_values.hpp.ejs', 'utf8'), {strict: true});
-writeIfModified(
-    `platform/android/src/style/conversion/types_string_values.hpp`,
-    enumPropertyHppTypeStringValueTemplate({properties: enumPropertiesDeDup})
-);
-
-// JNI property value types conversion templates
-const enumPropertyHppTypeTemplate = ejs.compile(fs.readFileSync('platform/android/src/style/conversion/types.hpp.ejs', 'utf8'), {strict: true});
-writeIfModified(
-    `platform/android/src/style/conversion/types.hpp`,
-    enumPropertyHppTypeTemplate({properties: enumPropertiesDeDup})
-);
diff --git a/platform/android/src/conversion/constant.hpp b/platform/android/src/conversion/constant.hpp
index a0675479552..0e665cf56a1 100644
--- a/platform/android/src/conversion/constant.hpp
+++ b/platform/android/src/conversion/constant.hpp
@@ -3,6 +3,8 @@
 #include "conversion.hpp"
 
 #include <mbgl/util/color.hpp>
+#include <mbgl/util/enum.hpp>
+
 #include <jni/jni.hpp>
 
 #include <string>
@@ -74,6 +76,13 @@ struct Converter<jni::jobject*, std::vector<float>> {
     Result<jni::jobject*> operator()(jni::JNIEnv& env, const std::vector<float>& value) const;
 };
 
+template <class T>
+struct Converter<jni::jobject*, T, typename std::enable_if_t<std::is_enum<T>::value>> {
+    Result<jni::jobject*> operator()(jni::JNIEnv& env, const T& value) const {
+        return convert<jni::jobject*, std::string>(env, Enum<T>::toString(value));
+    }
+};
+
 // Java -> C++
 
 template <>
diff --git a/platform/android/src/style/conversion/property_value.hpp b/platform/android/src/style/conversion/property_value.hpp
index e4d8f59ec3f..8150285c85d 100644
--- a/platform/android/src/style/conversion/property_value.hpp
+++ b/platform/android/src/style/conversion/property_value.hpp
@@ -6,7 +6,6 @@
 #include "../../conversion/conversion.hpp"
 #include "../../conversion/constant.hpp"
 #include "property_expression.hpp"
-#include "types.hpp"
 
 namespace mbgl {
 namespace android {
diff --git a/platform/android/src/style/conversion/types.hpp b/platform/android/src/style/conversion/types.hpp
deleted file mode 100644
index e87782fad0a..00000000000
--- a/platform/android/src/style/conversion/types.hpp
+++ /dev/null
@@ -1,119 +0,0 @@
-// This file is generated. Edit android/platform/scripts/generate-style-code.js, then run `make android-style-code`.
-#pragma once
-
-#include "types_string_values.hpp"
-#include "../../conversion/conversion.hpp"
-#include "../../conversion/constant.hpp"
-
-#include <mbgl/style/types.hpp>
-#include <mbgl/util/optional.hpp>
-#include <jni/jni.hpp>
-
-#include <string>
-
-namespace mbgl {
-namespace android {
-namespace conversion {
-
-template <>
-struct Converter<jni::jobject*, mbgl::style::VisibilityType> {
-    Result<jni::jobject*> operator()(jni::JNIEnv& env, const mbgl::style::VisibilityType& value) const {
-        return convert<jni::jobject*, std::string>(env, toString(value));
-    }
-};
-
-template <>
-struct Converter<jni::jobject*, mbgl::style::LineCapType> {
-    Result<jni::jobject*> operator()(jni::JNIEnv& env, const mbgl::style::LineCapType& value) const {
-        return convert<jni::jobject*, std::string>(env, toString(value));
-    }
-};
-
-template <>
-struct Converter<jni::jobject*, mbgl::style::LineJoinType> {
-    Result<jni::jobject*> operator()(jni::JNIEnv& env, const mbgl::style::LineJoinType& value) const {
-        return convert<jni::jobject*, std::string>(env, toString(value));
-    }
-};
-
-template <>
-struct Converter<jni::jobject*, mbgl::style::SymbolPlacementType> {
-    Result<jni::jobject*> operator()(jni::JNIEnv& env, const mbgl::style::SymbolPlacementType& value) const {
-        return convert<jni::jobject*, std::string>(env, toString(value));
-    }
-};
-
-template <>
-struct Converter<jni::jobject*, mbgl::style::AlignmentType> {
-    Result<jni::jobject*> operator()(jni::JNIEnv& env, const mbgl::style::AlignmentType& value) const {
-        return convert<jni::jobject*, std::string>(env, toString(value));
-    }
-};
-
-template <>
-struct Converter<jni::jobject*, mbgl::style::IconTextFitType> {
-    Result<jni::jobject*> operator()(jni::JNIEnv& env, const mbgl::style::IconTextFitType& value) const {
-        return convert<jni::jobject*, std::string>(env, toString(value));
-    }
-};
-
-template <>
-struct Converter<jni::jobject*, mbgl::style::SymbolAnchorType> {
-    Result<jni::jobject*> operator()(jni::JNIEnv& env, const mbgl::style::SymbolAnchorType& value) const {
-        return convert<jni::jobject*, std::string>(env, toString(value));
-    }
-};
-
-template <>
-struct Converter<jni::jobject*, mbgl::style::TextJustifyType> {
-    Result<jni::jobject*> operator()(jni::JNIEnv& env, const mbgl::style::TextJustifyType& value) const {
-        return convert<jni::jobject*, std::string>(env, toString(value));
-    }
-};
-
-template <>
-struct Converter<jni::jobject*, mbgl::style::TextTransformType> {
-    Result<jni::jobject*> operator()(jni::JNIEnv& env, const mbgl::style::TextTransformType& value) const {
-        return convert<jni::jobject*, std::string>(env, toString(value));
-    }
-};
-
-template <>
-struct Converter<jni::jobject*, mbgl::style::TranslateAnchorType> {
-    Result<jni::jobject*> operator()(jni::JNIEnv& env, const mbgl::style::TranslateAnchorType& value) const {
-        return convert<jni::jobject*, std::string>(env, toString(value));
-    }
-};
-
-template <>
-struct Converter<jni::jobject*, mbgl::style::CirclePitchScaleType> {
-    Result<jni::jobject*> operator()(jni::JNIEnv& env, const mbgl::style::CirclePitchScaleType& value) const {
-        return convert<jni::jobject*, std::string>(env, toString(value));
-    }
-};
-
-template <>
-struct Converter<jni::jobject*, mbgl::style::RasterResamplingType> {
-    Result<jni::jobject*> operator()(jni::JNIEnv& env, const mbgl::style::RasterResamplingType& value) const {
-        return convert<jni::jobject*, std::string>(env, toString(value));
-    }
-};
-
-template <>
-struct Converter<jni::jobject*, mbgl::style::HillshadeIlluminationAnchorType> {
-    Result<jni::jobject*> operator()(jni::JNIEnv& env, const mbgl::style::HillshadeIlluminationAnchorType& value) const {
-        return convert<jni::jobject*, std::string>(env, toString(value));
-    }
-};
-
-template <>
-struct Converter<jni::jobject*, mbgl::style::LightAnchorType> {
-    Result<jni::jobject*> operator()(jni::JNIEnv& env, const mbgl::style::LightAnchorType& value) const {
-        return convert<jni::jobject*, std::string>(env, toString(value));
-    }
-};
-
-
-} // namespace conversion
-} // namespace android
-} // namespace mbgl
diff --git a/platform/android/src/style/conversion/types.hpp.ejs b/platform/android/src/style/conversion/types.hpp.ejs
deleted file mode 100644
index 3cd47640158..00000000000
--- a/platform/android/src/style/conversion/types.hpp.ejs
+++ /dev/null
@@ -1,40 +0,0 @@
-<%
-  const properties = locals.properties;
--%>
-// This file is generated. Edit android/platform/scripts/generate-style-code.js, then run `make android-style-code`.
-#pragma once
-
-#include "types_string_values.hpp"
-#include "../../conversion/conversion.hpp"
-#include "../../conversion/constant.hpp"
-
-#include <mbgl/style/types.hpp>
-#include <mbgl/util/optional.hpp>
-#include <jni/jni.hpp>
-
-#include <string>
-
-namespace mbgl {
-namespace android {
-namespace conversion {
-
-template <>
-struct Converter<jni::jobject*, mbgl::style::VisibilityType> {
-    Result<jni::jobject*> operator()(jni::JNIEnv& env, const mbgl::style::VisibilityType& value) const {
-        return convert<jni::jobject*, std::string>(env, toString(value));
-    }
-};
-
-<% for (const property of properties) { -%>
-template <>
-struct Converter<jni::jobject*, mbgl::style::<%- propertyNativeType(property) %>> {
-    Result<jni::jobject*> operator()(jni::JNIEnv& env, const mbgl::style::<%- propertyNativeType(property) %>& value) const {
-        return convert<jni::jobject*, std::string>(env, toString(value));
-    }
-};
-
-<% } -%>
-
-} // namespace conversion
-} // namespace android
-} // namespace mbgl
diff --git a/platform/android/src/style/conversion/types_string_values.hpp b/platform/android/src/style/conversion/types_string_values.hpp
deleted file mode 100644
index 9f6696d1810..00000000000
--- a/platform/android/src/style/conversion/types_string_values.hpp
+++ /dev/null
@@ -1,257 +0,0 @@
-// This file is generated. Edit android/platform/scripts/generate-style-code.js, then run `make android-style-code`.
-#pragma once
-
-#include <mbgl/style/types.hpp>
-
-#include <string>
-#include <stdexcept>
-
-namespace mbgl {
-namespace android {
-namespace conversion {
-
-    // visibility
-    inline std::string toString(mbgl::style::VisibilityType value) {
-        switch (value) {
-          case mbgl::style::VisibilityType::Visible:
-            return "visible";
-            break;
-          case mbgl::style::VisibilityType::None:
-            return "none";
-            break;
-          default:
-            throw std::runtime_error("Not implemented");
-        }
-    }
-
-    // line-cap
-    inline std::string toString(mbgl::style::LineCapType value) {
-        switch (value) {
-          case mbgl::style::LineCapType::Butt:
-            return "butt";
-            break;
-          case mbgl::style::LineCapType::Round:
-            return "round";
-            break;
-          case mbgl::style::LineCapType::Square:
-            return "square";
-            break;
-          default:
-            throw std::runtime_error("Not implemented");
-        }
-    }
-
-    // line-join
-    inline std::string toString(mbgl::style::LineJoinType value) {
-        switch (value) {
-          case mbgl::style::LineJoinType::Bevel:
-            return "bevel";
-            break;
-          case mbgl::style::LineJoinType::Round:
-            return "round";
-            break;
-          case mbgl::style::LineJoinType::Miter:
-            return "miter";
-            break;
-          default:
-            throw std::runtime_error("Not implemented");
-        }
-    }
-
-    // symbol-placement
-    inline std::string toString(mbgl::style::SymbolPlacementType value) {
-        switch (value) {
-          case mbgl::style::SymbolPlacementType::Point:
-            return "point";
-            break;
-          case mbgl::style::SymbolPlacementType::Line:
-            return "line";
-            break;
-          case mbgl::style::SymbolPlacementType::LineCenter:
-            return "line-center";
-            break;
-          default:
-            throw std::runtime_error("Not implemented");
-        }
-    }
-
-    // icon-rotation-alignment
-    inline std::string toString(mbgl::style::AlignmentType value) {
-        switch (value) {
-          case mbgl::style::AlignmentType::Map:
-            return "map";
-            break;
-          case mbgl::style::AlignmentType::Viewport:
-            return "viewport";
-            break;
-          case mbgl::style::AlignmentType::Auto:
-            return "auto";
-            break;
-          default:
-            throw std::runtime_error("Not implemented");
-        }
-    }
-
-    // icon-text-fit
-    inline std::string toString(mbgl::style::IconTextFitType value) {
-        switch (value) {
-          case mbgl::style::IconTextFitType::None:
-            return "none";
-            break;
-          case mbgl::style::IconTextFitType::Width:
-            return "width";
-            break;
-          case mbgl::style::IconTextFitType::Height:
-            return "height";
-            break;
-          case mbgl::style::IconTextFitType::Both:
-            return "both";
-            break;
-          default:
-            throw std::runtime_error("Not implemented");
-        }
-    }
-
-    // icon-anchor
-    inline std::string toString(mbgl::style::SymbolAnchorType value) {
-        switch (value) {
-          case mbgl::style::SymbolAnchorType::Center:
-            return "center";
-            break;
-          case mbgl::style::SymbolAnchorType::Left:
-            return "left";
-            break;
-          case mbgl::style::SymbolAnchorType::Right:
-            return "right";
-            break;
-          case mbgl::style::SymbolAnchorType::Top:
-            return "top";
-            break;
-          case mbgl::style::SymbolAnchorType::Bottom:
-            return "bottom";
-            break;
-          case mbgl::style::SymbolAnchorType::TopLeft:
-            return "top-left";
-            break;
-          case mbgl::style::SymbolAnchorType::TopRight:
-            return "top-right";
-            break;
-          case mbgl::style::SymbolAnchorType::BottomLeft:
-            return "bottom-left";
-            break;
-          case mbgl::style::SymbolAnchorType::BottomRight:
-            return "bottom-right";
-            break;
-          default:
-            throw std::runtime_error("Not implemented");
-        }
-    }
-
-    // text-justify
-    inline std::string toString(mbgl::style::TextJustifyType value) {
-        switch (value) {
-          case mbgl::style::TextJustifyType::Left:
-            return "left";
-            break;
-          case mbgl::style::TextJustifyType::Center:
-            return "center";
-            break;
-          case mbgl::style::TextJustifyType::Right:
-            return "right";
-            break;
-          default:
-            throw std::runtime_error("Not implemented");
-        }
-    }
-
-    // text-transform
-    inline std::string toString(mbgl::style::TextTransformType value) {
-        switch (value) {
-          case mbgl::style::TextTransformType::None:
-            return "none";
-            break;
-          case mbgl::style::TextTransformType::Uppercase:
-            return "uppercase";
-            break;
-          case mbgl::style::TextTransformType::Lowercase:
-            return "lowercase";
-            break;
-          default:
-            throw std::runtime_error("Not implemented");
-        }
-    }
-
-    // fill-translate-anchor
-    inline std::string toString(mbgl::style::TranslateAnchorType value) {
-        switch (value) {
-          case mbgl::style::TranslateAnchorType::Map:
-            return "map";
-            break;
-          case mbgl::style::TranslateAnchorType::Viewport:
-            return "viewport";
-            break;
-          default:
-            throw std::runtime_error("Not implemented");
-        }
-    }
-
-    // circle-pitch-scale
-    inline std::string toString(mbgl::style::CirclePitchScaleType value) {
-        switch (value) {
-          case mbgl::style::CirclePitchScaleType::Map:
-            return "map";
-            break;
-          case mbgl::style::CirclePitchScaleType::Viewport:
-            return "viewport";
-            break;
-          default:
-            throw std::runtime_error("Not implemented");
-        }
-    }
-
-    // raster-resampling
-    inline std::string toString(mbgl::style::RasterResamplingType value) {
-        switch (value) {
-          case mbgl::style::RasterResamplingType::Linear:
-            return "linear";
-            break;
-          case mbgl::style::RasterResamplingType::Nearest:
-            return "nearest";
-            break;
-          default:
-            throw std::runtime_error("Not implemented");
-        }
-    }
-
-    // hillshade-illumination-anchor
-    inline std::string toString(mbgl::style::HillshadeIlluminationAnchorType value) {
-        switch (value) {
-          case mbgl::style::HillshadeIlluminationAnchorType::Map:
-            return "map";
-            break;
-          case mbgl::style::HillshadeIlluminationAnchorType::Viewport:
-            return "viewport";
-            break;
-          default:
-            throw std::runtime_error("Not implemented");
-        }
-    }
-
-    // anchor
-    inline std::string toString(mbgl::style::LightAnchorType value) {
-        switch (value) {
-          case mbgl::style::LightAnchorType::Map:
-            return "map";
-            break;
-          case mbgl::style::LightAnchorType::Viewport:
-            return "viewport";
-            break;
-          default:
-            throw std::runtime_error("Not implemented");
-        }
-    }
-
-
-} // namespace conversion
-} // namespace android
-} // namespace mbgl
diff --git a/platform/android/src/style/conversion/types_string_values.hpp.ejs b/platform/android/src/style/conversion/types_string_values.hpp.ejs
deleted file mode 100644
index bf529197412..00000000000
--- a/platform/android/src/style/conversion/types_string_values.hpp.ejs
+++ /dev/null
@@ -1,48 +0,0 @@
-<%
-  const properties = locals.properties;
--%>
-// This file is generated. Edit android/platform/scripts/generate-style-code.js, then run `make android-style-code`.
-#pragma once
-
-#include <mbgl/style/types.hpp>
-
-#include <string>
-#include <stdexcept>
-
-namespace mbgl {
-namespace android {
-namespace conversion {
-
-    // visibility
-    inline std::string toString(mbgl::style::VisibilityType value) {
-        switch (value) {
-          case mbgl::style::VisibilityType::Visible:
-            return "visible";
-            break;
-          case mbgl::style::VisibilityType::None:
-            return "none";
-            break;
-          default:
-            throw std::runtime_error("Not implemented");
-        }
-    }
-
-<% for (const property of properties) { -%>
-    // <%- property.name %>
-    inline std::string toString(mbgl::style::<%- propertyNativeType(property) %> value) {
-        switch (value) {
-<% for (const value in property.values) { -%>
-          case mbgl::style::<%- propertyNativeType(property) %>::<%- camelize(value) %>:
-            return "<%- value %>";
-            break;
-<% } -%>
-          default:
-            throw std::runtime_error("Not implemented");
-        }
-    }
-
-<% } -%>
-
-} // namespace conversion
-} // namespace android
-} // namespace mbgl

From 165beb153f7324a64b828145aa30e24ea50573d5 Mon Sep 17 00:00:00 2001
From: John Firebaugh <john.firebaugh@gmail.com>
Date: Mon, 20 Aug 2018 11:09:00 -0700
Subject: [PATCH 4/4] [android] Inline geometry conversion

---
 .../src/geojson/conversion/feature.cpp        |  3 +--
 .../src/geojson/conversion/geometry.hpp       | 24 -------------------
 2 files changed, 1 insertion(+), 26 deletions(-)
 delete mode 100644 platform/android/src/geojson/conversion/geometry.hpp

diff --git a/platform/android/src/geojson/conversion/feature.cpp b/platform/android/src/geojson/conversion/feature.cpp
index 8dff05aa124..3cb6d37b17b 100644
--- a/platform/android/src/geojson/conversion/feature.cpp
+++ b/platform/android/src/geojson/conversion/feature.cpp
@@ -1,5 +1,4 @@
 #include "feature.hpp"
-#include "geometry.hpp"
 
 #include "../../conversion/constant.hpp"
 #include "../../conversion/conversion.hpp"
@@ -161,7 +160,7 @@ Result<jni::Object<android::geojson::Feature>> Converter<jni::Object<android::ge
     auto properties = jni::Object<gson::JsonObject>(*convert<jni::jobject*>(env, value.properties));
 
     // Convert geometry
-    auto geometry = *convert<jni::Object<android::geojson::Geometry>>(env, value.geometry);
+    auto geometry = android::geojson::Geometry::New(env, value.geometry);
 
     // Create feature
     auto feature = android::geojson::Feature::fromGeometry(env, geometry, properties, jid);
diff --git a/platform/android/src/geojson/conversion/geometry.hpp b/platform/android/src/geojson/conversion/geometry.hpp
deleted file mode 100644
index 242a68df02e..00000000000
--- a/platform/android/src/geojson/conversion/geometry.hpp
+++ /dev/null
@@ -1,24 +0,0 @@
-#pragma once
-
-#include <mapbox/geometry.hpp>
-#include "../geometry.hpp"
-#include <jni/jni.hpp>
-
-namespace mbgl {
-namespace android {
-namespace conversion {
-
-/**
- * mapbox::geometry::geometry<T> -> Java GeoJson Geometry
- */
-template <class T>
-struct Converter<jni::Object<android::geojson::Geometry>, mapbox::geometry::geometry<T>> {
-    Result<jni::Object<android::geojson::Geometry>> operator()(jni::JNIEnv& env, const mapbox::geometry::geometry<T>& value) const {
-       return { android::geojson::Geometry::New(env, value) };
-    }
-};
-
-
-} // conversion
-} // android
-} // mbgl