Java
6 minute read
Overview
The AWS SDK for Java provides a Java API for AWS services. Using the SDK, your Java application can interact with LocalStack services the same way it does with Amazon services. Support for new services is regularly added to the SDK. For a list of the supported services and their API versions that are included with each release of the SDK, view the release notes for the version that you’re working with.
The Java SDK currently supports two major versions:
Examples
Full examples for both SDK versions can be found in the example repository. This includes proper exception handling and all the necessary Maven dependencies. The scripts to create the AWS services on LocalStack can be found under the src/main/resources folder of each module in the repository.
S3 Service
Below you’ll find an example of how to create an S3 client with the endpoint configured for LocalStack. The client can be used to upload a file to an existing bucket and then retrieve it.
Configuring the S3 Client
Interacting with S3
DynamoDB Service
Another interesting case is interacting with the DynamoDB service. Here we can see code snippets of a DynamoDB client inserting an entity of type Person into a table with the same name. Once the object is in the database, we would like to retrieve it as well. Just like the example before, the scripts to create the AWS services on LocalStack can be found under the src/main/resources folder of each module in the repository.
Pay particular attention to the handling of the data model in the v2 example. As part of improvements, some boilerplate code can be abstracted with the help of specific annotations, which help label the Java bean, the partition key and even specify converters for certain data types. Unfortunately, the enhanced mapping in v2 does not support Date type, but a handwritten converter is enough to cater to the application’s needs. The full list of supported converters can be found here.