If Apache is not configured with 'AllowEncodedSlashes On', dashboard links will be broken : for instance http://localhost:9000/dashboard/index/com.sonarsource.it.samples:simple-sample:src%2Fmain%2Fjava%2Fsample%2FSample.java?metric=function_complexity will return a 404 error.
This is because "%2f" is allowed in a query string. but not in a URL (See this thread for more details : http://serverfault.com/questions/142591/apache-rewriterule-and-slashes-2f/142609#142609).
We should change the dashboard url to /dashboard/index?id=...
More details can be seen in the mailing list : http://sonarqube.15.x6.nabble.com/sonar-dev-Fwd-Most-Violated-Components-Hotspots-by-Lines-of-code-broken-in-4-4-td5027502.html