المصدر: help me in java problem ,,, في منتدى : قسم الكومبيوتر العام ( حل مشاكل - تبادل خبرات ) I have mac EL Capitan, 10.11.5, I used RWeka package, it downloaded correctly and initialized with any error, but when I apply J48(Species~., data = iris) I have this error Error in .jnew("weka/core/Attribute", attname,.jcast(levels,"java/util/List")): java.lang.UnsupportedClassVersionError: weka/core/Attribute:Unsupported major.minor version 51.0 I used java version with these details, 52F85:~ kameljabreen$ java -version java version "1.7.0_79"Java(TM) SE RuntimeEnvironment(build 1.7.0_79-b15)JavaHotSpot(TM)64-BitServer VM (build 24.79-b02, mixed mode) Please help me to solve this problems, it is my problm since one month, I read a lot about this problem in web sites. I did all thing, installing java JDK version 1.8 .... ect. now I used java 1.7. Please give me solutions. Thanks in advance