I have a disgusting and annoying problem that has been bothering me for hours. I have a .java file. It is associated with /usr/java/jdk1.8.0_121/bin/. I try to move it back where I can open it via Kwrite. Now I right-click on the file. I follow that way: Properties > **General **> File Type Options > **Application Preference Order. **
Then I remove javaws and java. After that I see a tiny windows says ‘Updating System Configuration’. Then nothing changes. Everything goes back.
I figured out to open .JAVA files with this method: Right Click on file > Open With > **Other… **> Choose Kwrite then click Remember Application Association for all files of type “Java source code” (text/x-java)
Problem is solved. But openSUSE is too stubborn. Such a shame.