Separate java primitive arrays and implement Iterable (#1798)

It was not possible to implement Dart's `Iterable` in a generic way for both primitive arrays and object arrays. Now the primitive arrays are separate and they all implement `Iterable`.

Author: HosseinYousefi

pkgs/jni/CHANGELOG.md

@@ -1,5 +1,14 @@
 ## 0.13.0-wip
 
+- **Breaking Change**: Separated primitive arrays from object arrays.
+  Previously, a primitive array like an array of bytes was typed
+  `JArray<jbyte>`. Now `JArray<T>` only accepts `JObject`s as types and
+  primitive arrays like arrays of bytes have their own types such as
+  `JByteArray`.
+
+  This enables all arrays to implement `Iterable` which makes it possible to use
+  them in a for-loop or use methods such as `map` on them.
+
 - Added nullable type classes for all Java objects.
 
 ## 0.12.2

pkgs/jni/lib/_internal.dart

@@ -34,7 +34,6 @@ export 'src/method_invocation.dart';
 export 'src/types.dart'
     show
         JAccessible,
-        JArrayElementType,
         JCallable,
         JConstructable,
         JObjType,

pkgs/jni/lib/jni.dart

@@ -63,6 +63,7 @@ library;
 export 'package:ffi/ffi.dart' show Arena, using;
 
 export 'src/errors.dart';
+export 'src/jarray.dart';
 export 'src/jimplementer.dart';
 export 'src/jni.dart' hide ProtectedJniExtensions, StringMethodsForJni;
 export 'src/jobject.dart';
@@ -75,7 +76,6 @@ export 'src/third_party/generated_bindings.dart'
 export 'src/types.dart'
     hide
         JAccessible,
-        JArrayElementType,
         JCallable,
         JConstructable,
         JObjType,