I remembered that in the old versions of eclipse(maybe 3.1), in the package and project explorer, it will show the current java class that is opened in the editor. When I change to another java class, it the explorer will automatically scroll to display the new class.
It seems this feature is gone in later release.
But the fact is that it is hidden - by default disabled, to enable it, you just need toggle the"Link with Editor" button in Package/Project/ or Navigator toolbar.
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