SONAR FINDBUGS expect compiled Java class files while analysing

Hi,

We are using SONARQUBE 7.6 and sonar-findbugs-plugin-3.11.0.jar .

When we analyze, sonar expects compiled java class files.

even though we have set the below property in sonar-project.properties file.
sonar.java.binaries=.

please help to analyze the project without class files!

Error log:
WARN: Findbugs needs sources to be compiled. Please build project before executing sonar or check the location of compiled classes to make it possible for Findbugs to analyse your (sub)project (/var/fpwork1/SONAR7.6_WORKSPACE_LIVE/EM/connection).
INFO: ------------------------------------------------------------------------
INFO: EXECUTION FAILURE
INFO: ------------------------------------------------------------------------
INFO: Total time: 23.382s
INFO: Final Memory: 26M/912M
INFO: ------------------------------------------------------------------------
ERROR: Error during SonarQube Scanner execution
ERROR: Can not execute Findbugs
ERROR: Caused by: One (sub)project contains Java source files that are not compiled (/var/fpwork1/SONAR7.6_WORKSPACE_LIVE/EM/connection).
ERROR:
ERROR: Re-run SonarQube Scanner using the -X switch to enable full debug logging.