I use a maven standard directory layout for my projects.
The image Below is a typical project explorer view of a "not so minimum working example" of the view I want to customize.
As you can see, all the relevant folders are marked as source folders, so there is no need to show the src folder hierarchy as it is shown below the included libraries.
So the question is, how can I get rid of the redundant src folder showing, i.e. how to show only source folders and libraries?
I've playing around with filters and content configuration of the view but couldn't find the way to do it.
Click to the third right top button, then "Filters" and then check "Name filter patterns" and write "src". Then the second src folder is hidden.
This is actually not added twice it is because of the explorer view you are using, just change it to navigator view and your problem will get solved.
Check this post might help you more, it is not related to you answer but show how to select navigator view Hope this will help you :).
The description in Andreas B.'s answer refers to the Package Explorer view. In Project Explorer view it's:
View Menu → Filters and Customization... → User filters → New → src → activate/check it → OK
来源：https://stackoverflow.com/questions/14437227/how-to-hide-src-folder-from-eclipse-project-explorer