Modifying an existing application to use DAX

If you already have a Java application that uses Amazon DynamoDB, you can modify it so that it can access your DynamoDB Accelerator (DAX) cluster. You don't have to rewrite the entire application because the DAX Java client is similar to the DynamoDB low-level client included in the AWS SDK for Java 2.x. See Working with items in DynamoDB for details.

To modify your program, replace the DynamoDB client with a DAX client.

Region region = Region.US_EAST_1;

// Create an asynchronous DynamoDB client
DynamoDbAsyncClient client = DynamoDbAsyncClient.builder()
                .region(region)
                .build();

// Create an asynchronous DAX client
DynamoDbAsyncClient client = ClusterDaxAsyncClient.builder()
                .overrideConfiguration(Configuration.builder()
                    .url(<cluster url>) // for example, "dax://my-cluster.l6fzcv.dax-clusters.us-east-1.amazonaws.com"
                    .region(region)
                    .addMetricPublisher(cloudWatchMetricsPub) // optionally enable SDK metric collection
                    .build())
                .build();

You can also use the high-level library that is part of the AWS SDK for Java 2.x, replacing the DynamoDB client with a DAX client.

Region region = Region.US_EAST_1;
DynamoDbAsyncClient dax = ClusterDaxAsyncClient.builder()
        .overrideConfiguration(Configuration.builder()
            .url(<cluster url>) // for example, "dax://my-cluster.l6fzcv.dax-clusters.us-east-1.amazonaws.com"
            .region(region)
            .build())
        .build();

DynamoDbEnhancedAsyncClient enhancedClient = DynamoDbEnhancedAsyncClient.builder()
        .dynamoDbClient(dax)
        .build();

For more information, see Mapping items in DynamoDB tables.