how can view document (doc,docx,pdf,xls,xlsx) on line, no download?

how to view document on line in javaweb project? now, i convert document to pdf with openoffice4 ,then convert pdf to swf by swftools, then view the swf file in web browser by flexpaper. the process openoffice4 often cause mistake. it usually cant exit normally.

and i tried microsoft Office Web Viewer, http://ift.tt/1NMfGRR, but it cant open my document in tomcat server.

is there any good way to view office document on-line?