[android] use shared DefaultFileSource for all maps + OfflineManager

platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/offline/OfflineManager.java

@@ -32,13 +32,6 @@ public class OfflineManager {
   // Default database name
   private static final String DATABASE_NAME = "mbgl-offline.db";
 
-  /*
-   * The maximumCacheSize parameter is a limit applied to non-offline resources only,
-   * i.e. resources added to the database for the "ambient use" caching functionality.
-   * There is no size limit for offline resources.
-   */
-  private static final long DEFAULT_MAX_CACHE_SIZE = 50 * 1024 * 1024;
-
   // Holds the pointer to JNI DefaultFileSource
   private long mDefaultFileSourcePtr = 0;
 
@@ -93,9 +86,9 @@ public class OfflineManager {
    */
   private OfflineManager(Context context) {
     // Get a pointer to the DefaultFileSource instance
-    String assetRoot = getDatabasePath(context);
-    String cachePath = assetRoot + File.separator + DATABASE_NAME;
-    mDefaultFileSourcePtr = createDefaultFileSource(cachePath, assetRoot, DEFAULT_MAX_CACHE_SIZE);
+    String cachePath = getDatabasePath(context) + File.separator + DATABASE_NAME;
+    String apkPath = context.getPackageCodePath();
+    mDefaultFileSourcePtr = sharedDefaultFileSource(cachePath, apkPath);
     setAccessToken(mDefaultFileSourcePtr, Mapbox.getAccessToken());
 
     // Delete any existing previous ambient cache database
@@ -284,8 +277,8 @@ public class OfflineManager {
   /*
    * Native methods
    */
-  private native long createDefaultFileSource(
-    String cachePath, String assetRoot, long maximumCacheSize);
+  private native long sharedDefaultFileSource(
+    String cachePath, String assetRoot);
 
   private native void setAccessToken(long defaultFileSourcePtr, String accessToken);
 

platform/android/config.cmake

@@ -45,6 +45,8 @@ macro(mbgl_platform_core)
         PRIVATE platform/default/default_file_source.cpp
         PRIVATE platform/default/local_file_source.cpp
         PRIVATE platform/default/online_file_source.cpp
+        PRIVATE platform/android/src/default_file_source.cpp
+        PRIVATE platform/android/src/default_file_source.hpp
 
         # Offline
         # PRIVATE include/mbgl/storage/offline.hpp

platform/android/src/default_file_source.cpp

@@ -0,0 +1,20 @@
+#include "default_file_source.hpp"
+#include <mbgl/util/logging.hpp>
+
+#include <cassert>
+
+namespace mbgl {
+namespace android {
+
+DefaultFileSource& defaultFileSource(const std::string& cachePath_, const std::string& assetRoot_) {
+    static auto cachePath = cachePath_;
+    assert(cachePath == cachePath_);
+    static auto assetRoot = assetRoot_;
+    assert(assetRoot == assetRoot_);
+
+    static DefaultFileSource defaultFileSource{ cachePath, assetRoot };
+    return defaultFileSource;
+}
+
+} // namespace android
+} // namespace mbgl

platform/android/src/default_file_source.hpp

@@ -0,0 +1,12 @@
+#pragma once
+
+#include <mbgl/storage/default_file_source.hpp>
+
+namespace mbgl {
+namespace android {
+
+DefaultFileSource& defaultFileSource(const std::string& cachePath = ":memory:",
+                                     const std::string& assetRoot = ".");
+
+} // namespace android
+} // namespace mbgl

platform/android/src/jni.cpp

@@ -14,6 +14,7 @@
 #include "bitmap.hpp"
 #include "bitmap_factory.hpp"
 #include "connectivity_listener.hpp"
+#include "default_file_source.hpp"
 #include "style/functions/categorical_stops.hpp"
 #include "style/functions/exponential_stops.hpp"
 #include "style/functions/identity_stops.hpp"
@@ -1290,12 +1291,9 @@ void nativeScheduleTakeSnapshot(JNIEnv *env, jni::jobject* obj, jlong nativeMapV
 
 // Offline calls begin
 
-jlong createDefaultFileSource(JNIEnv *env, jni::jobject* obj, jni::jstring* cachePath_, jni::jstring* assetRoot_, jlong maximumCacheSize) {
-    std::string cachePath = std_string_from_jstring(env, cachePath_);
-    std::string assetRoot = std_string_from_jstring(env, assetRoot_);
-    mbgl::DefaultFileSource *defaultFileSource = new mbgl::DefaultFileSource(cachePath, assetRoot, maximumCacheSize);
-    jlong defaultFileSourcePtr = reinterpret_cast<jlong>(defaultFileSource);
-    return defaultFileSourcePtr;
+jlong sharedDefaultFileSource(JNIEnv *env, jni::jobject* obj, jni::jstring* cachePath_, jni::jstring* assetRoot_) {
+    return reinterpret_cast<jlong>(&defaultFileSource(std_string_from_jstring(env, cachePath_),
+                                                      std_string_from_jstring(env, assetRoot_)));
 }
 
 void setAccessToken(JNIEnv *env, jni::jobject* obj, jlong defaultFileSourcePtr, jni::jstring* accessToken_) {
@@ -1984,7 +1982,7 @@ void registerNatives(JavaVM *vm) {
     offlineManagerClassPtrId = &jni::GetFieldID(env, offlineManagerClass, "mDefaultFileSourcePtr", "J");
 
     jni::RegisterNatives(env, offlineManagerClass,
-        MAKE_NATIVE_METHOD(createDefaultFileSource, "(Ljava/lang/String;Ljava/lang/String;J)J"),
+        MAKE_NATIVE_METHOD(sharedDefaultFileSource, "(Ljava/lang/String;Ljava/lang/String;)J"),
         MAKE_NATIVE_METHOD(setAccessToken, "(JLjava/lang/String;)V"),
         MAKE_NATIVE_METHOD(getAccessToken, "(J)Ljava/lang/String;"),
         MAKE_NATIVE_METHOD(listOfflineRegions, "(JLcom/mapbox/mapboxsdk/offline/OfflineManager$ListOfflineRegionsCallback;)V"),

platform/android/src/native_map_view.cpp

@@ -1,5 +1,6 @@
 #include "native_map_view.hpp"
 #include "jni.hpp"
+#include "default_file_source.hpp"
 
 #include <cstdlib>
 #include <ctime>
@@ -27,6 +28,7 @@ NativeMapView::NativeMapView(JNIEnv *env_, jobject obj_, float pixelRatio, int a
     : env(env_),
       availableProcessors(availableProcessors_),
       totalMemory(totalMemory_),
+      fileSource(defaultFileSource(mbgl::android::cachePath + "/mbgl-offline.db", mbgl::android::apkPath)),
       threadPool(4) {
 
     assert(env_ != nullptr);
@@ -43,13 +45,9 @@ NativeMapView::NativeMapView(JNIEnv *env_, jobject obj_, float pixelRatio, int a
         return;
     }
 
-    fileSource = std::make_unique<mbgl::DefaultFileSource>(
-        mbgl::android::cachePath + "/mbgl-offline.db",
-        mbgl::android::apkPath);
-
     map = std::make_unique<mbgl::Map>(
         *this, mbgl::Size{ static_cast<uint32_t>(width), static_cast<uint32_t>(height) },
-        pixelRatio, *fileSource, threadPool, MapMode::Continuous);
+        pixelRatio, fileSource, threadPool, MapMode::Continuous);
 
     float zoomFactor   = map->getMaxZoom() - map->getMinZoom() + 1;
     float cpuFactor    = availableProcessors;
@@ -71,7 +69,6 @@ NativeMapView::~NativeMapView() {
     assert(obj != nullptr);
 
     map.reset();
-    fileSource.reset();
 
     env->DeleteWeakGlobalRef(obj);
 
@@ -198,7 +195,9 @@ void NativeMapView::render() {
 
 mbgl::Map &NativeMapView::getMap() { return *map; }
 
-mbgl::DefaultFileSource &NativeMapView::getFileSource() { return *fileSource; }
+mbgl::DefaultFileSource& NativeMapView::getFileSource() {
+    return fileSource;
+}
 
 void NativeMapView::initializeDisplay() {
     assert(display == EGL_NO_DISPLAY);

platform/android/src/native_map_view.hpp

@@ -96,7 +96,7 @@ private:
     size_t totalMemory = 0;
 
     // Ensure these are initialised last
-    std::unique_ptr<mbgl::DefaultFileSource> fileSource;
+    mbgl::DefaultFileSource& fileSource;
     mbgl::ThreadPool threadPool;
     std::unique_ptr<mbgl::Map> map;
     mbgl::EdgeInsets insets;