Deploy Java Lambda functions with container images

You can deploy your Lambda function code as a container image. AWS provides the following resources to help you build a container image for your Java function:

• AWS base images for Lambda

  These base images are preloaded with a language runtime and other components that are required to run the image on Lambda. AWS provides a Dockerfile for each of the base images to help with building your container image.

  For runtimes that use the Amazon Linux 2 operating system, AWS provides base images for x86_64 architecture and arm64 architecture.

• Open-source runtime interface clients (RIC)

  If you use a community or private enterprise base image, you must add a Runtime interface client to the base image to make it compatible with Lambda.

• Open-source runtime interface emulator (RIE)

  Lambda provides a runtime interface emulator for you to test your function locally. The base images for Lambda and base images for custom runtimes include the RIE. For other base images, you can download the RIE for testing your image locally.

The workflow for a function defined as a container image includes these steps:

1. Build your container image using the resources listed in this topic.

2. Upload the image to your Amazon ECR container registry. See steps 7-9 in Create image.

3. Create the Lambda function or update the function code to deploy the image to an existing function.

AWS base images for Java

AWS provides the following base images for Java:

Tags	Runtime	Operating system	Dockerfile
11	Java 11 (Corretto)	Amazon Linux 2	Dockerfile for Java 11 on GitHub
8.al2	Java 8 (Corretto)	Amazon Linux 2	Dockerfile for Java 8.al2 on GitHub
8	Java 8 (OpenJDK)	Amazon Linux 2018.03	Dockerfile for Java 8 on GitHub

Docker Hub repository: amazon/aws-lambda-java

Amazon ECR repository: gallery.ecr.aws/lambda/java

Using a Java base image

For instructions on how to use a Java base image, choose the usage tab on Lambda base images for Java in the Amazon ECR repository.

The instructions are also available on Lambda base images for Java in the Docker Hub repository.

Java runtime interface clients

Install the runtime interface client for Java using the Apache Maven package manager. Add the following to your pom.xml file:

<dependency>
    <groupId>com.amazonaws</groupId>
    <artifactId>aws-lambda-java-runtime-interface-client</artifactId>
    <version>1.0.0</version>
</dependency>

For package details, see Lambda RIC in Maven Central Repository.

You can also view the Java client source code in the AWS Lambda Java Support Libraries repository on GitHub.

After your container image resides in the Amazon ECR container registry, you can create and run the Lambda function.

Deploy the container image

For a new function, you deploy the Java image when you create the function. For an existing function, if you rebuild the container image, you need to redeploy the image by updating the function code.