<Swing Dev> RFR: 8247753: UIManager.getSytemLookAndFeelClassName() returns wrong value on Fedora 32
Prasanta Sadhukhan
prasanta.sadhukhan at oracle.com
Thu Aug 6 10:01:56 UTC 2020
+1
Regards
Prasanta
On 06-Aug-20 1:23 AM, Philip Race wrote:
> Approved.
>
> -phil.
>
> On 8/5/20, 11:22 AM, Pankaj Bansal wrote:
>>
>> Hello Phil,
>>
>> I have made the changes you suggested.
>>
>> webrev: http://cr.openjdk.java.net/~pbansal/8247753/webrev02/
>> <http://cr.openjdk.java.net/%7Epbansal/8247753/webrev02/>
>>
>> <<I am assuming that you have a reason for both toLowerCase() and
>> contains() rather than equals() ?
>>
>> Yes, in some distros XDG_CURRENT_DESKTOP is set to some string
>> containing "gnome" string, but not exactly "gnome". For example, on
>> Ubuntu 18.04, it is "ubuntu:GNOME". I could have used "endsWith"
>> method as of now, but for more inclusiveness, I have used contains,
>> so we don't have to change again if some distro decides to set
>> XDG_CURRENT_DESKTOP to something not covered by "endsWith".
>>
>> Regards,
>>
>> Pankaj
>>
>>
>>
>> On 05/08/20 9:35 PM, Philip Race wrote:
>>> I've read the bug comments and it looks like you've eventually come
>>> to the right answer.
>>> I just would code it differently for a couple of reasons
>>> 1) To make it easier some day to remove checking the old variable by
>>> just deleting a few lines
>>> 2) To avoid repeating the string literal which I always think of as
>>> error-prone
>>>
>>> I am assuming that you have a reason for both toLowerCase() and
>>> contains() rather than equals() ?
>>>
>>> diff --git a/src/java.desktop/unix/classes/sun/awt/UNIXToolkit.java
>>> b/src/java.desktop/unix/classes/sun/awt/UNIXToolkit.java
>>> --- a/src/java.desktop/unix/classes/sun/awt/UNIXToolkit.java
>>> +++ b/src/java.desktop/unix/classes/sun/awt/UNIXToolkit.java
>>> @@ -95,10 +95,19 @@
>>>
>>> @Override
>>> public String getDesktop() {
>>> + String gnome = "gnome";
>>> String gsi = AccessController.doPrivileged(
>>> (PrivilegedAction<String>) ()
>>> ->
>>> System.getenv("GNOME_DESKTOP_SESSION_ID"));
>>> - return (gsi != null) ? "gnome" : null;
>>> + if (gsi != null) {
>>> + return gnome;
>>> + }
>>> + String desktop = AccessController.doPrivileged(
>>> + (PrivilegedAction<String>) ()
>>> + -> System.getenv("XDG_CURRENT_DESKTOP"));
>>> + return (desktop != null &&
>>> desktop.toLowerCase().contains(gnome))
>>> + ? gnome : null;
>>> +
>>> }
>>>
>>> -phil.
>>>
>>> On 8/4/20, 10:16 PM, Prasanta Sadhukhan wrote:
>>>>
>>>> Looks ok to me.
>>>>
>>>> One observation is, in testcase you can remove line71 linux check
>>>> as we already did the check in l54.
>>>>
>>>> Regards
>>>> Prasanta
>>>> On 04-Aug-20 11:12 PM, Pankaj Bansal wrote:
>>>>>
>>>>> Hi All,
>>>>>
>>>>> Please review the following fix for jdk16.
>>>>>
>>>>> Bug : https://bugs.openjdk.java.net/browse/JDK-8247753
>>>>> webrev: http://cr.openjdk.java.net/~pbansal/8247753/webrev00
>>>>> <http://cr.openjdk.java.net/%7Epbansal/8247753/webrev00>
>>>>>
>>>>> Bug: UIManager.getSytemLookAndFeelClassName() returns wrong value
>>>>> on Fedora 32. It is returning the MetalLookAndFeel classname
>>>>> instead of GTKLookAndFeel classname.
>>>>>
>>>>> Cause: Java uses a environment variable GNOME_DESKTOP_SESSION_ID
>>>>> to verify if the system is gnome (which is set by gnome) and then
>>>>> checks for GTKLookAndFeel support. If both conditions are
>>>>> satisfied, then GTKLookAndFeel classname is returned, else cross
>>>>> platform MetalLookAndFeel is selected.
>>>>>
>>>>> The GNOME_DESKTOP_SESSION_ID environment has been |deprecated| for
>>>>> a long time and the value is set to "|this-is-deprecated|" by
>>>>> gnome. In java, the actual value of variable is not being
>>>>> verified. As long as the value is not null (it has been set to
>>>>> something by gnome), things have been working fine though the
>>>>> value set by gnome is "|this-is-deprecated|". Now, gnome has
>>>>> removed the variable completely and this is causing issues in
>>>>> Fedora 32. As the variable is not set at all, java is returning
>>>>> the cross platform MetalLookAndFeel classname for the
>>>>> SystemLookAndFeelClassName instead of GTKLookAndFeel.
>>>>>
>>>>> More information on this in JBS. Right now the issue is seen only
>>>>> on Fedora 32, but this can very well come in future releases of
>>>>> RHEL, CentOS, Oracle Linux etc.
>>>>>
>>>>> Fix: We should check XDG_CURRENT_DESKTOP also along with
>>>>> GNOME_DESKTOP_SESSION_ID to verify gnome based linux.
>>>>> XDG_CURRENT_DESKTOP is set by gnome based platforms to some string
>>>>> containing "gnome" substring. So, this can be used to verify the
>>>>> gnome based desktop. For backward compatibility, we need to
>>>>> continue checking GNOME_DESKTOP_SESSION_ID as well because for
>>>>> some linux platforms, XDG_CURRENT_DESKTOP may be set to something
>>>>> else as they are not gnome based, but have been returning GTKL&F
>>>>> as GNOME_DESKTOP_SESSION_ID was set by them. so, we dont want to
>>>>> change anything for them.
>>>>>
>>>>> Other solution could have been to just make GTKL&F default on all
>>>>> linux, but that would result in GTKL&F being selected on some new
>>>>> platfoms like KDE based platforms where currently Metal L&F is
>>>>> selected.
>>>>>
>>>>> I have modified the test case
>>>>> test/jdk/javax/swing/LookAndFeel/SystemLookAndFeel/SystemLookAndFeelTest.java.
>>>>> The test fails on Fedora 32 without fix and passes with the fix. I
>>>>> have run the required mach5 tests and this fix is not breaking
>>>>> anything. Link in JBS.
>>>>>
>>>>>
>>>>> Regards,
>>>>>
>>>>> Pankaj Bansal
>>>>>
>>
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