If you have problems running self signed Java Apps in Linux since Java 1.7.0_51, you can lower the security level in the control panel. To start the control panel for java, execute:

/usr/java/latest/bin/ControlPanel


assuming that you have installed the rpm.

If you want to change it in the config files, you have to add:

deployment.security.level=MEDIUM


in the file .java/deployment/deployment.properties in your home.

If you dont want to lower the security slider, you can add exceptions in URL-form in the control panel or in .java/deployment/security/exception.sites