IntelliJ IDEA
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Determining Template Data Language by a File Extension
When using FreeMarker or Velocity with IntelliJ IDEA, you sometimes need to change the underlying language for a template to enable coding assistance and syntax highlighting.
As with IntelliJ IDEA 8.1, you can open the Settings Dialog and select Template Data Languages to specify what language should be applied to a single template, or an entire folder containing template files. IntelliJ IDEA Velocity integration is also capable of determining the language by a double file extension (e.g. foo.java.vm or bar.css.ft).
In the upcoming EAP for IntelliJ IDEA 8.1.1 you will find another way of mapping files to various template languages: open the Settings dialog, select File Types, and click Add or Edit under Registered Patterns.