[9] Review request: 8177566: FX user module gets IllegalAccessException from sun.reflect.misc.Trampoline

[Kevin Rushforth]

OK, I'll create a more informative message. I think it will be more 
clear in the message to just say that it needs to "open" the package to 
javafx.base, since that would be the recommendation for a package that 
isn't already exported unconditionally. I'll send out a new webrev this 
morning with all feedback incorporated.

-- Kevin


Mandy Chung wrote:
>> On May 2, 2017, at 2:22 PM, Kevin Rushforth <kevin.rushforth at oracle.com> wrote:
>>
>> Here is the message:
>>
>> IllegalAccessException: class com.sun.javafx.property.MethodHelper cannot access class com.foo (in module foo.app) because module foo.app does not open com.foo to javafx.base 
>>
>>     
>
> It would be better to emit a more informative message e.g. “javafx.base cannot access class com.foo (in module foo.app).  Either exports com.foo unqualifiedly or open com.foo to javafx.base”.  Also in MethodUtil::invoke
>   61            if (!module.isExported(packageName)) {
> You can do this check only if module.isNamed.
>
>   
>> It is roughly the same message that any similar illegal access would generate (e.g., we get similar error messages when FXML tries to call setAccessible for a field annotated with @FXML if the module is not "open" to javafx.fxml).
>>
>>     
>>> javafx.base/src/main/java/com/sun/javafx/property/MethodHelper.java
>>> javafx.fxml/src/main/java/com/sun/javafx/fxml/MethodHelper.java
>>> javafx.web/src/main/java/com/sun/webkit/MethodHelper.java
>>>   45     public static Object invoke(Method m, Object obj, Object[] params)
>>>
>>> To avoid 3 ModuleHelper classes, the invoke method can take
>>> the callerModule argument to replace this line: 
>>>   56         final Module thisModule = MethodHelper.class.getModule();
>>>   
>>>       
>> I'm fairly certain that won't work. Module::addOpens is caller sensitive and will only work when called from the module in question.
>>
>>     
>
> You are right.  Wont’t work.
>   
>>> javafx.base/src/main/java/com/sun/javafx/reflect/MethodUtil.java
>>>   There are a few other public methods which I think JavaFX doesn’t
>>>   need and can be removed.
>>>   
>>>       
>> Yes, I could do this to reduce the public footprint of the class. To minimize the diffs between the original and our copy, I might just comment out the "public". That would also make it easier to add them back in a future version (e.g., to eventually get rid of all dependency on sun.reflect.misc). Thoughts?
>>     
>
> I will leave it up to you.
> Mandy
>
>