libreoffice recommend default-jre | openjdk-8-jre | openjdk-7-jre | openjdk-6-jre | gcj-jre | sun-java5-jre | sun-java6-jre | java5-runtime | jre,
i would suggest to go with default-jre in case one dont need oracle-jave. I would hereby suggest to let java 7 go and use java 8, it is old enough now.