I downloaded jar file of eXist-1.0.2-rev5396 and installed this with command: java -jar eXist-1.0.2-rev5396.jar and after that ran exist  with clicking on "exist database startup" on desktop and then i could easily import this class:
import org.xmldb.api.*;
import org.xmldb.api.base.*;
import org.xmldb.api.modules.*;
to the my web application(my servlets). but after that when i want to import this class in other application after running jetty servlet ("exist database startup"), i couldn't add this class to that application. can anybody help  me?