Getting Started with Amazon Corretto 21 on Docker Images

This topic describes how to build and launch a Docker image that uses Amazon Corretto 21. You must have the latest version of Docker installed.

Using the official image for Amazon Corretto 21.

Amazon Corretto 21 is available as an official image on Docker Hub. The following example runs a container and displays Corretto 21's version.

Example

docker run amazoncorretto:21 java -version

Output:

Example

openjdk version "21.0.10" 2026-01-20 LTS
OpenJDK Runtime Environment Corretto-21.0.10.7.1 (build 21.0.10+7-LTS)
OpenJDK 64-Bit Server VM Corretto-21.0.10.7.1 (build 21.0.10+7-LTS, mixed mode, sharing)

Using the Corretto ECR Instance

To use the Corretto ECR instance, run the following commands:

Example

docker pull public.ecr.aws/amazoncorretto/amazoncorretto:21
docker run -it public.ecr.aws/amazoncorretto/amazoncorretto:21 /bin/bash

You can see the list of available images by going here:

Amazon Corretto on Alpine

Amazon Corretto on Alpine Linux images are available on Amazon ECR Public Gallery and Dockerhub

Using dockerhub

Example

docker pull amazoncorretto:21-alpine-jdk
docker run -it amazoncorretto:21-alpine-jdk /bin/sh

Build a Docker Image with Amazon Corretto 21

Run the following command to build an image that uses Amazon Corretto 21.

Example

docker build -t amazon-corretto-21 github.com/corretto/corretto-docker#main:21/jdk/al2023

After the command completes, you have an image called amazon-corretto-21.

To launch this image locally, run the following command.

Example

docker run -it amazon-corretto-21

You can also push this image to Amazon ECR. See the Pushing an Image topic in the Amazon Elastic Container Registry User Guide for details.

Create an Image

You can create a new Docker image using Corretto's official Docker Hub image.

1. Create a Dockerfile with the following content.

   Example

   FROM amazoncorretto:21
   RUN echo $' \
   public class Hello { \
   public static void main(String[] args) { \
   System.out.println("Welcome to Amazon Corretto!"); \
   } \
   }' > Hello.java
   RUN javac Hello.java
   CMD ["java", "Hello"] 

2. Build the new image.

   Example

   docker build -t hello-app .

3. Run the new image.

   Example

   docker run hello-app

   You get the following output.

   Welcome to Amazon Corretto!