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The TabSheet component has no way of enumerating tabs, so there is no way to dynamically change a tab tile / caption if you do not save each tab when you added it. I have a framework running on top of Vaadin which allows me to present an entire app that was written in a meta language as a web application. The text translation for custom pages are done dynamically based on the original captions, but there is no way to enumerate pages on a TabSheet component. I worked around this by subclassing the component. But even then, the variable containing the list of tabs is private, so a subclass cannot access it, so I have to keep a seperate list of tabs by overriding addTab(). There should be getTabs() function as part of TabSheet class.