Bash function to switch jdk version in the terminal session only.

setjdk.sh

# Function to switch JDK versions
# Usage:
#    > setjdk     # switch to latest jdk
#    > setjdk 8   # switch to jdk 1.8
#    > setjdk 11  # switch to jdk 11
function setjdk() {
  oldStyleVersion=8
  requestedVersion=$1
  finalVersion=""

  # Figure out the version
  if [ $# -eq 0 ]; then
     echo "Setting to latest Java version"
  elif [ $requestedVersion -gt $oldStyleVersion ]; then
     echo "Switching to Java version: $1";
     finalVersion="-v $1";
  else
     echo "Switching to Java version: $1";
     finalVersion="-v 1.$1";
  fi

  # Set the version
  export JAVA_HOME=$(/usr/libexec/java_home $finalVersion);
  java -version;
}

Looks like this: