Improve the performance of JNI calls by making JNI calls require a
Context object. LocalRef inherits from Context and can make calls
directly. Non-local Ref classes will generate a Context object when
making a call. The patch also makes the template design cleaner in
several cases.
This patch adds specializations of jni::Ref for primitive arrays like
IntArray and FloatArray, so that the arrays can be accessed through the
GetElement, GetElements, and Length members.
When we have a Java exception in native code, the Java stack in the
exception will not be very useful because the top frame is the native
entry point. In this case, the native stack is more useful. However,
currently we don't get a good native stack in this situation because we
go through Java when handling the exception, and the native stack we get
will have a lot of unknown frames inside libdvm or libart. This patch
makes us stay in native code when handling an uncaught exception from
native code, so that we get a good native stack.
Add a direct ownership model where the Java object owns the
corresponding C++ object directly, in addition to the WeakPtr model
where the Java object owns a WeakPtr to the C++ object. The WeakPtr
model is chosen when the implementing C++ class inherits from
SupportsWeakPtr. Otherwise, the direct ownership model is chosen. Under
the direct ownership model, a UniquePtr object must be used to attach
the containing C++ object to a Java object, to ensure ownership is
passed on to the Java object.
This patch adds:
* Conversion operator from String::Param to String::LocalRef.
* More overloads of the jni::ThrowException function.
* name members to built-in types like jni::Object, jni::String, etc.
This allows using jni::Accessors::EnsureClassRef on built-in types
to get built-in class refs (e.g. jclass for java/lang/String).
* Ability to implicitly convert LocalRef<Cls> to LocalRef<Object>
* Fixes for bugs in LocalRef/GlobalRef where new refs are not created.
* Fixes for inaccurate uses of mozilla::Forward in favor of mozilla::Move
We use Ref::From() inside TypeAdapter<Ref>::ToNative to convert a raw JNI
ref argument to a Ref argument for the C++ function. However, that
generates a compile error, unless we make TypeAdapter<Ref> a friend of
Ref, because we intentionally made Ref's copy constructor private and
returning from TypeAdapter<Ref>::ToNative requires the copy constructor.
Introduce a JNIObject class that serves as a base class for classes
that wish to use per-instance native methods. JNIObject includes a long
native pointer field that the C++ code accesses to associate the Java
object instance with a C++ object instance.