Work with an existing table

The previous section showed how to create a DynamoDB table starting with a Java data class. If you already have an existing table and want to use the features of the enhanced client, you can create a Java data class to work with the table. You need to examine the DynamoDB table and add the necessary annotations to the data class.

Before you work with an existing table, call the DynamoDbEnhanced.table() method. This was done in the previous example with the following statement.

DynamoDbTable<Customer> customerTable = enhancedClient.table("Customer", TableSchema.fromBean(Customer.class));

After the DynamoDbTable instance is returned, you can begin working right away with the underlying table. You do not need to recreate the table by calling the DynamoDbTable.createTable() method.

The following example demonstrates this by immediately retrieving a Customer instance from the DynamoDB table.

DynamoDbTable<Customer> customerTable = enhancedClient.table("Customer", TableSchema.fromBean(Customer.class));
// The Customer table exists already and has an item with a primary key value of "1" and a sort key value of "customer@example.com".
customerTable.getItem(
        Key.builder().
                partitionValue("1").
                sortValue("customer@example.com").build());