IntelliJ IDEA includes the Struts Assistant plugin that provides the native support for Struts framework. See the Live Struts Demo

This plugin adds the Struts support to:

• Project view
  Lets you navigate through the native Struts application structure and examine its elements (Struts HTML and JSP pages, Struts actions, beans, etc)
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• Properties inspector
  Lets you explore and edit property files through the set of dedicated GUI editors. Also supports nested beans.
• Coding assistance
  Fully extends code completion, navigation, highlighting, documentation lookup and refactoring for Struts (including Struts HTML tags), Tiles and Struts Validator files.
  Also extends the standard actions, like Go to Symbol (Ctrl+Alt+Shift+N) with support for Actions, Forms, Forwards and Tiles.
• Quick fixes
  Struts-aware quick fixes and intention actions let you instantly correct various errors, for example, invalid Struts mappings.
• Comma-delimited lists supported (roles, Struts Validator rules)