highlighting word using lucene search engine

[kumar]

 
Give an example to highlight a given word in  a single text file using an apache lucene.  

[Hugo <Nabble>]

I am not sure I understand your question. Nabble highlights the search criteria on pages found by the search engine. For example, go to:
http://n2.nabble.com/forum/Search.jtp?forum=1&local=y&query=embed
and then click on a given result. You will see yellow highlights on the interface.