Install default-jdk-headless by entering the following commands in the terminal:
sudo apt update sudo apt install default-jdk-headless
Standard Java or Java compatible Development Kit (headless)
This dependency package points to the Java runtime, or Java compatible development kit recommended for this architecture, which is openjdk-11-jdk-headless for amd64. . The package is used as dependency for packages not needing a graphical display during runtime.