<Swing Dev> Review-request for 8145547: JEP 283: [AWT/Swing] Conditional support for GTK 3 on Linux

[Sergey Bylokhov]

On 21.03.16 23:38, Semyon Sadetsky wrote:
>> This does not solve the problem when check/init/load will try to use
>> the different versions. I guess I provided enough arguments to
>> initialize these data only once.
> I've already explained that GTK library cannot be loaded twice, only one
> version may be loaded regardless of the property value.

We already found that there is a problem in synchronization, there is 
some other cases, which can be introduced in the future. To eliminate 
even the possibility of such missconfigurationion, it would be better 
try to load only the one version which was set by "jdk.gtk.version" for 
the first time. It will solve bunch of possible issues.

>> It will be better to make it obvious and not to depends on some order.
>> I am curious where you find it widely used. At least in the client I
>> found only one usage.
> I can help you. Look at GTKEngine.java: WidgetType, StateType, Settings,
> ShadowType, Orientation, PositionType, etc...

Thanks, this all in one file of gtk look and feel. This is a bad 
pattern, and we should not copy it to the UnixToolkit class. For 
additional information read the spec of ordinal method and "Effective 
Java" by Josh Bloch Item 31.

Also I am not sure that I understand where we survive the hang which can 
occur if we try to load the gtk library if it was loaded before by the 
other applications(like fx or swt).

-- 
Best regards, Sergey.