You should explore the contents of this project. It demonstrates a CDK app with an instance of a stack (CdkWorkshopStack)
which contains an Amazon SQS queue that is subscribed to an Amazon SNS topic.
The cdk.json file tells the CDK Toolkit how to execute your app.
It is a Maven based project, so you can open this project with any Maven compatible Java IDE to build and run tests.
mvn packagecompile and run testscdk lslist all stacks in the appcdk synthemits the synthesized CloudFormation templatecdk deploydeploy this stack to your default AWS account/regioncdk diffcompare deployed stack with current statecdk docsopen CDK documentation
Enjoy!