When I build the project with dependencies, it gives this error.

Failed to execute goal org.apache.maven.plugins:maven-javadoc-plugin:2.10.4:jar (attach-javadocs) on project appointmentscheduling-api: MavenReportException: Error while generating Javadoc:

Previously I could build it properly. I didn't change anything, I tried a backup sample as well. But this error come always. Tried re-installing javadoc plugin. There are some answers which says to change the pom.xml file. They didn't work for me either. Somebody help me to solve this please.

Thanks in advance