Edit hadoop-config.sh in libexec, add these lines on top, not the path is specific to your java home
export JAVA_HOME="/Library/Java/JavaVirtualMachines/jdk1.8.0_152.jdk/Contents/Home" export JRE_ENV="/Library/Java/JavaVirtualMachines/jdk1.8.0_152.jdk/Contents/Home" export JRE_HOME="/Library/Java/JavaVirtualMachines/jdk1.8.0_152.jdk/Contents/Home"