PetStoreClient.java

import software.amazon.awssdk.services.dynamodb.model.ScanRequest;
import software.amazon.awssdk.services.dynamodb.model.ScanResponse;

....

public List<Pet> read() {

  final ScanRequest scanRequest = ScanRequest.builder()
      .tableName("pet-store")
      .build();

  final ScanResponse scanResponse = dynamoDbClient.scan(scanRequest);
  final List<Map<String, AttributeValue>> returnedItems = scanResponse.items();
  final List<Pet> pets = new ArrayList<>();
  returnedItems.forEach(item -> {
    final Pet pet = new Pet();
    pet.setId(item.get("id").s());
    pet.setName(item.get("name").s());
    pet.setAge(Integer.parseInt(item.get("age").n()));
    pet.setCategory(item.get("category").s());
    pets.add(pet);
  });
  return pets;
}