1343027 - Add JNI wrappers for casting and locking

Status: RESOLVED FIXED

(Core Graveyard :: Widget: Android, defect)

Description

[(inactive) Jim Chen [:jchen] [:darchons]]

Add wrappers for casting one type to another type, and for locking an object.

Comment 1

[(inactive) Jim Chen [:jchen] [:darchons]]

Attachment: 1. Add jni::Ref::Cast function (v1)

Add a Cast function to jni::Ref to cast a reference to a different type
(e.g. if ref is a jni::Object::Ref referring to a String instance, use |
ref.Cast<jni::String>()->Length() | to get the length of the string).

In MOZ_CHECK_JNI builds, Cast() checks that an instance of the source
class can indeed be cast to the target class.

Comment 2

[(inactive) Jim Chen [:jchen] [:darchons]]

Attachment: 2. Add jni::Ref::Lock function (v1)

Add a Lock function to jni::Ref to lock the referenced object akin to
the synchronized keyword in Java. It returns a Locked RAII object that
automatically unlocks the object when going out of scope.

Comment 3

[James Willcox (:snorp) ([e-mail]) (he/him)]

Comment on attachment 8842204 [details] [diff] [review]
1. Add jni::Ref::Cast function (v1)

Review of attachment 8842204 [details] [diff] [review]:
-----------------------------------------------------------------

This is super nice.

Comment 4

[James Willcox (:snorp) ([e-mail]) (he/him)]

Comment on attachment 8842205 [details] [diff] [review]
2. Add jni::Ref::Lock function (v1)

Review of attachment 8842205 [details] [diff] [review]:
-----------------------------------------------------------------

::: widget/android/jni/Refs.h
@@ +78,5 @@
>  
>  public:
>      using JNIType = Type;
>  
> +    class Locked

AutoLock? AutoMonitor? AutoMutex? It should have Auto in it.

Comment 5

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/mozilla-inbound/rev/a97e11f9a6e2
1. Add jni::Ref::Cast function; r=snorp
https://hg.mozilla.org/integration/mozilla-inbound/rev/1af35d88e88b
2. Add jni::Ref::Lock function; r=snorp

Comment 6

[Carsten Book [:Tomcat]]

https://hg.mozilla.org/mozilla-central/rev/a97e11f9a6e2
https://hg.mozilla.org/mozilla-central/rev/1af35d88e88b