BoxStore: access context and relinker fields through methods.

However, still setting static field from constructor. Not sure of better solution, yet.

Author: greenrobot-team

objectbox-java/src/main/java/io/objectbox/BoxStore.java

@@ -60,8 +60,8 @@
 public class BoxStore implements Closeable {
 
     /** On Android used for native library loading. */
-    @Nullable public static Object context;
-    @Nullable public static Object relinker;
+    @Nullable private static Object context;
+    @Nullable private static Object relinker;
 
     /** Change so ReLinker will update native library when using workaround loading. */
     public static final String JNI_VERSION = "2.6.0-RC";
@@ -73,6 +73,18 @@ public class BoxStore implements Closeable {
     private static final Set<String> openFiles = new HashSet<>();
     private static volatile Thread openFilesCheckerThread;
 
+    @Nullable
+    @Internal
+    public static synchronized Object getContext() {
+        return context;
+    }
+
+    @Nullable
+    @Internal
+    public static synchronized Object getRelinker() {
+        return relinker;
+    }
+
     /**
      * Convenience singleton instance which gets set up using {@link BoxStoreBuilder#buildDefault()}.
      * <p>

objectbox-java/src/main/java/io/objectbox/internal/NativeLibraryLoader.java

@@ -181,22 +181,22 @@ private static void checkUnpackLib(String filename) {
     }
 
     private static boolean loadLibraryAndroid() {
-        if (BoxStore.context == null) {
+        if (BoxStore.getContext() == null) {
             return false;
         }
 
         //noinspection TryWithIdenticalCatches
         try {
             Class<?> context = Class.forName("android.content.Context");
-            if (BoxStore.relinker == null) {
+            if (BoxStore.getRelinker() == null) {
                 // use default ReLinker
                 Class<?> relinker = Class.forName("com.getkeepsafe.relinker.ReLinker");
                 Method loadLibrary = relinker.getMethod("loadLibrary", context, String.class, String.class);
-                loadLibrary.invoke(null, BoxStore.context, OBJECTBOX_JNI, BoxStore.JNI_VERSION);
+                loadLibrary.invoke(null, BoxStore.getContext(), OBJECTBOX_JNI, BoxStore.JNI_VERSION);
             } else {
                 // use custom ReLinkerInstance
-                Method loadLibrary = BoxStore.relinker.getClass().getMethod("loadLibrary", context, String.class, String.class);
-                loadLibrary.invoke(BoxStore.relinker, BoxStore.context, OBJECTBOX_JNI, BoxStore.JNI_VERSION);
+                Method loadLibrary = BoxStore.getRelinker().getClass().getMethod("loadLibrary", context, String.class, String.class);
+                loadLibrary.invoke(BoxStore.getRelinker(), BoxStore.getContext(), OBJECTBOX_JNI, BoxStore.JNI_VERSION);
             }
         } catch (NoSuchMethodException e) {
             return false;