According to this thread and this blog post :
See " eclipse look & feel customization " for details.
Everyone sees this " java-tips ":

To change the shape of the view title, the next line of code can be written in the preWindowOpen() method of ApplicationWorkbenchWindowAdvisor .
PlatformUI.getPreferenceStore().setValue(IWorkbenchPreferenceConstants.SHOW_TRADITIONAL_STYLE_TABS, false);
Please note that there may be a problem with long headers when there are many tabs:
See error 322623 :
"Editor tabs do not display ellipsis for long file names when using new-style tabs."
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