How to Remove OpenJDK Ubuntu

step 1)Check Version
          #java -version

step 2) First check the current setup before we uninstall Java
            #sudo update-alternatives --display java
           OR
             #sudo update-alternatives --config java

step 3)Check which JDK packages are installed
            #sudo dpkg --list | grep -i jdk

            #Remove Java
            #sudo apt-get purge icedtea-* openjdk-*

Check that all JDK packages have been removed
#sudo dpkg --list | grep -i jdk