How to write custom eclipse formatter for a custom file type (text)

I'd like to write an eclipse formatter for a custom file type (text based). The goal is to format tabular text data like Fitnesse does, for example:

|column1   | column 2 |
|5|6|

When formatted would appear as:

| column1 | column 2 |
| 5       | 6        |

I don't think the code would be hard to write and I may be able to get the algorithm from fitnesse, but I don't know how to write the plugin for eclipse.

Thanks