Downloading and Installing Java from OpenJDK
if you want to download OpenJDK manually, download it from https://jdk.java.net/
But you can download JDK programmatically as the following. Java SE 7, 8, 9, 10, 11, 12, 13 are included below script. So, run below script in your terminal.
# Java SE 7
wget https://download.java.net/openjdk/jdk7u75/ri/openjdk-7u75-b13-linux-x64-18_dec_2014.tar.gz
# Java SE 8
wget https://download.java.net/openjdk/jdk8u40/ri/openjdk-8u40-b25-linux-x64-10_feb_2015.tar.gz
# Java SE 9
wget https://download.java.net/java/GA/jdk9/9.0.4/binaries/openjdk-9.0.4_linux-x64_bin.tar.gz
# Java SE 10
wget https://download.java.net/java/GA/jdk10/10.0.2/19aef61b38124481863b1413dce1855f/13/openjdk-10.0.2_linux-x64_bin.tar.gz
# Java SE 11
wget https://download.java.net/java/GA/jdk11/9/GPL/openjdk-11.0.2_linux-x64_bin.tar.gz
# Java SE 12
wget https://download.java.net/java/GA/jdk12.0.2/e482c34c86bd4bf8b56c0b35558996b9/10/GPL/openjdk-12.0.2_linux-x64_bin.tar.gz
# Java SE 13
wget https://download.java.net/java/GA/jdk13/5b8a42f3905b406298b72d750b6919f6/33/GPL/openjdk-13_linux-x64_bin.tar.gz
mkdir /usr/lib/jvm
# Extract all downloaded jdk files
tar -xvzf openjdk-7u75-b13-linux-x64-18_dec_2014.tar.gz -C /usr/lib/jvm
tar -xvzf openjdk-8u40-b25-linux-x64-10_feb_2015.tar.gz -C /usr/lib/jvm
tar -xvzf openjdk-9.0.4_linux-x64_bin.tar.gz -C /usr/lib/jvm
tar -xvzf openjdk-10.0.2_linux-x64_bin.tar.gz -C /usr/lib/jvm
tar -xvzf openjdk-11.0.2_linux-x64_bin.tar.gz -C /usr/lib/jvm
tar -xvzf openjdk-12.0.2_linux-x64_bin.tar.gz -C /usr/lib/jvm
tar -xvzf openjdk-13_linux-x64_bin.tar.gz -C /usr/lib/jvm
# Remove downloaded jdk files
rm openjdk*
# Install Java and Java Compiler to Environment
update-alternatives --install /usr/bin/java java /usr/lib/jvm/java-se-7u75-ri/bin/java 1
update-alternatives --install /usr/bin/javac javac /usr/lib/jvm/java-se-7u75-ri/bin/javac 1
update-alternatives --install /usr/bin/java java /usr/lib/jvm/java-se-8u40-ri/bin/java 2
update-alternatives --install /usr/bin/javac javac /usr/lib/jvm/java-se-8u40-ri/bin/javac 2
update-alternatives --install /usr/bin/java java /usr/lib/jvm/jdk-9.0.4/bin/java 3
update-alternatives --install /usr/bin/javac javac /usr/lib/jvm/jdk-9.0.4/bin/javac 3
update-alternatives --install /usr/bin/java java /usr/lib/jvm/jdk-10.0.2/bin/java 4
update-alternatives --install /usr/bin/javac javac /usr/lib/jvm/jdk-10.0.2/bin/javac 4
update-alternatives --install /usr/bin/java java /usr/lib/jvm/jdk-11.0.2/bin/java 5
update-alternatives --install /usr/bin/javac javac /usr/lib/jvm/jdk-11.0.2/bin/javac 5
update-alternatives --install /usr/bin/java java /usr/lib/jvm/jdk-12.0.2/bin/java 6
update-alternatives --install /usr/bin/javac javac /usr/lib/jvm/jdk-12.0.2/bin/javac 6
update-alternatives --install /usr/bin/java java /usr/lib/jvm/jdk-13/bin/java 7
update-alternatives --install /usr/bin/javac javac /usr/lib/jvm/jdk-13/bin/javac 7
# Verify Java and Java Compiler Installation
# check if java command is pointing to correct path in system
update-alternatives --display java
update-alternatives --display javac
# List all environment variables
update-alternatives --get-selections
# or
update-alternatives --get-selections | grep java
# or
update-alternatives --get-selections | grep ^java
Check Java Version
# Verify if Java is running
java -version
# Verify if Java Compiler is running
javac -version