Custom script to download and install Oracle JDK from archive file

jdk_install.sh

#!/bin/bash

# This is a custom script to download and install Oracle JDK from archive file
# Please note that this script was only tested only on:
#     Raspberry Pi 5 running Raspberry Pi OS (64-bit) (Debian Bookworm port)
# This script is provided as is and you are free to use it at your own risk
# The author is not responsible for any damage caused by this script

if [ "$(id -u)" -ne 0 ]; then
    echo "Please run as root with sudo -i command"
    exit 1
fi

hw_arch=$(uname -m)
if [ "$hw_arch" = "aarch64" ]; then
    hw_arch="aarch64"
elif [ "$hw_arch" = "x86_64" ]; then
    hw_arch="x64"
else
    echo "Unsupported hardware architecture"
    exit 1
fi

echo "Enter the Oracle JDK version to be installed"
read version

if [ -z "$version" ]; then
    echo "Version cannot be empty"
    exit 1
fi

filename="jdk-$(echo $version)_linux-$(echo $hw_arch)_bin.tar.gz"

url="https://download.oracle.com/java/$version/latest/$filename"
sha256_url="https://download.oracle.com/java/$version/latest/$filename.sha256"

echo "Downloading the jdk tar.gz file"
wget -nc $url

echo "Downloading the sha256 file"
wget -nc $sha256_url

echo "Verifying the sha256 checksum"
if ! [ "$(sha256sum $filename | cut -d' ' -f1)" = "$(cat $filename.sha256)" ]; then
    echo "Checksum verification failed"
    exit 1
fi

folder=$(tar -tf $filename | head -n 1 | cut -f1 -d"/")
priority=$(echo $folder | cut -d'-' -f2 | awk -F. '{printf "%d%02d\n", $1, $3}')

echo "Extracting the jdk tar.gz file"
tar -xzf $filename -C /opt

echo "Setting up the alternatives"
for binary in /opt/$folder/bin/*; do
    if [ -x "$binary" ]; then
        echo "Processing $binary"
        update-alternatives --install /usr/bin/$(basename "$binary") $(basename "$binary") "$binary" $priority
        update-alternatives --display  $(basename "$binary")
        echo ""
    fi
done

exit 0