Install Java Runtime 1.8
sudo yum install java-1.8.0
or if you need a java compiler and other developer tools:
sudo yum install java-1.8.0-openjdk-devel
Then use the alternatives command to make Java 1.8 the default.
sudo /usr/sbin/alternatives --config java
sudo /usr/sbin/alternatives --config javac
# etc
If you prefer you can remove Java 1.7 with
sudo yum remove java-1.7.0-openjdk
but remove it after you installed Java 1.8 or the aws-apitools will also be removed as they depend on Java on being installed.