Using 'tag list' for java source code editing I discovered the following:
If you have a file containing multiple classes 'tag list' will display all members, methods and so on in one list. So what 'tag list' does is grouping members, methods, etc. by file.
Is there a way to make 'tag list' group this information not by file but by class?
I know that a workaround would be to define just one class per file but when working on already existing projects you can't just change the way classes are organised. Also I'm not to sure that defining only one class per file is always the right decision.
Yes, that's indeed how the Taglist plugin works. You can try the alternative Tagbar - Display tags of the current file ordered by scope plugin. This separates the members of the individual classes, but only shows the tags of the current (single) file, not an accumulated list like Taglist.