How can I solve java lang unsatisfiedlink error when runing jdeveloper?
Take a look here - the answer appears to correspond to your needs. It appears to be more of a progamming question than a DBA one, but we're here to help! :-). 

Furthermore, a quick Google of sudo yum install libXext got me to this link. Please take the statckexchange site tour and in particular, check out the "help us to help you" blog - both available at the bottom of the page on the left.