Insert in DynamoDB Using Java (Guide w/ Code Examples)

PutItem writes a complete item. Adding attribute_not_exists(pk) makes this a create-only operation instead of replacing an item with the same full primary key.

This example uses Java 17+ and the software.amazon.awssdk:dynamodb SDK 2.x dependency. Configure an AWS Region and credentials through your usual AWS profile or runtime role. The Orders table has String keys pk and sk; adapt the table and keys to your schema.

import java.util.*;
import software.amazon.awssdk.services.dynamodb.DynamoDbClient;
import software.amazon.awssdk.services.dynamodb.model.*;

public class Example {
    static AttributeValue s(String value) { return AttributeValue.builder().s(value).build(); }
    static Map<String, AttributeValue> key(String order) {
        return Map.of("pk", s("CUSTOMER#123"), "sk", s(order));
    }

    public static void main(String[] args) throws InterruptedException {
        try (DynamoDbClient ddb = DynamoDbClient.create()) {
            Map<String, AttributeValue> item = new HashMap<>(key("ORDER#001"));
            item.put("status", s("PENDING"));
            ddb.putItem(PutItemRequest.builder().tableName("Orders")
                .item(item).conditionExpression("attribute_not_exists(pk)").build());
        }
    }
}

Reference: AWS PutItem API. For related access patterns, see DynamoDB query examples.