I do have few Word templates, and my requirement is to replace some of the words/place holders in the document based on the user input, using Java. I tried lot of libraries
Try Apache POI. POI can work with doc and docx, but docx is more documented therefore support of it better.
POI
doc
docx
UPD: You can use XDocReport, which use POI. Also I recomend to use xlsx for templates because it more suitable and more documented
xlsx