Hi,
WebRatio 7.x does not support the 1.8 version of the jdk, you have to use jdk 1.7 or earlier releases.
Anyway this does not force you to uninstall jdk v 1.8 as you can just set the JAVA_HOME environment variable in order to use one or the other jdk version.
To know more about you can refer to this resource http://stackoverflow.com/questions/6588390/where-is-java-home-on-osx-yosemite-10-10-mavericks-10-9-mountain-lion-10
Best regards,
Lucio B.