Quickstart: Build a Java application using Azure Cosmos DB SQL API account

This quickstart shows how to create and manage resources of an Azure Cosmos DB SQL API account by using a Java application. First, you create an Azure Cosmos DB SQL API account using the Azure portal, create a Java app using the SQL Java SDK, add resources to your Cosmos DB account by using the Java application. The instructions in this quickstart can be followed on any operating system that is capable of running Java. After completing this quickstart you'll be familiar with creating and modifying Cosmos DB databases, containers in either the UI or programmatically, whichever is your preference.

Prerequisites

If you don't have an Azure subscription, create a free account before you begin.

You can Try Azure Cosmos DB for free without an Azure subscription, free of charge and commitments. Or, you can use the Azure Cosmos DB Emulator with a URI of https://localhost:8081. The Primary Key is provided in Authenticating requests.

In addition:

  • Java Development Kit (JDK) version 8
    • Be sure to set the JAVA_HOME environment variable to point to the folder where the JDK is installed.
  • Download and install a Maven binary archive
    • On Ubuntu, you can run apt-get install maven to install Maven.
  • Git
    • On Ubuntu, you can run sudo apt-get install git to install Git.

Create a database account

Before you can create a document database, you need to create a SQL API account with Azure Cosmos DB.

  1. Sign in to the Azure portal.

  2. Select Create a resource > Databases > Azure Cosmos DB.

    The Azure portal Databases pane

  3. On the Create Azure Cosmos DB Account page, enter the basic settings for the new Azure Cosmos account.

    Setting Value Description
    Subscription Subscription name Select the Azure subscription that you want to use for this Azure Cosmos account.
    Resource Group Resource group name Select a resource group, or select Create new, then enter a unique name for the new resource group.
    Account Name Enter a unique name Enter a name to identify your Azure Cosmos account. Because documents.azure.com is appended to the ID that you provide to create your URI, use a unique ID.

    The ID can only contain lowercase letters, numbers, and the hyphen (-) character. It must be between 3-31 characters in length.
    API Core (SQL) The API determines the type of account to create. Azure Cosmos DB provides five APIs: Core (SQL) and MongoDB for document data, Gremlin for graph data, Azure Table, and Cassandra. Currently, you must create a separate account for each API.

    Select Core (SQL) to create a document database and query by using SQL syntax.

    Learn more about the SQL API.
    Location Select the region closest to your users Select a geographic location to host your Azure Cosmos DB account. Use the location that is closest to your users to give them the fastest access to the data.

    The new account page for Azure Cosmos DB

  4. Select Review + create. You can skip the Network and Tags sections.

  5. Review the account settings, and then select Create. It takes a few minutes to create the account. Wait for the portal page to display Your deployment is complete.

    The Azure portal Notifications pane

  6. Select Go to resource to go to the Azure Cosmos DB account page.

    The Azure Cosmos DB account page

Add a container

You can now use the Data Explorer tool in the Azure portal to create a database and container.

  1. Select Data Explorer > New Container.

    The Add Container area is displayed on the far right, you may need to scroll right to see it.

    The Azure portal Data Explorer, Add Container pane

  2. In the Add container page, enter the settings for the new container.

    Setting Suggested value Description
    Database ID Tasks Enter ToDoList as the name for the new database. Database names must contain from 1 through 255 characters, and they cannot contain /, \\, #, ?, or a trailing space. Check the Provision database throughput option, it allows you to share the throughput provisioned to the database across all the containers within the database. This option also helps with cost savings.
    Throughput 400 Leave the throughput at 400 request units per second (RU/s). If you want to reduce latency, you can scale up the throughput later.
    Container ID Items Enter Items as the name for your new container. Container IDs have the same character requirements as database names.
    Partition key /category The sample described in this article uses /category as the partition key.

    In addition to the preceding settings, you can optionally add Unique keys for the container. Let's leave the field empty in this example. Unique keys provide developers with the ability to add a layer of data integrity to the database. By creating a unique key policy while creating a container, you ensure the uniqueness of one or more values per partition key. To learn more, refer to the Unique keys in Azure Cosmos DB article.

    Select OK. The Data Explorer displays the new database and container.

Add sample data

You can now add data to your new collection using Data Explorer.

  1. In Data Explorer, the new database appears in the Collections pane. Expand the Tasks database, expand the Items collection, click Documents, and then click New Documents.

    Create new documents in Data Explorer in the Azure portal

  2. Now add a document to the collection with the following structure.

    {
        "id": "1",
        "category": "personal",
        "name": "groceries",
        "description": "Pick up apples and strawberries.",
        "isComplete": false
    }
    
  3. Once you've added the json to the Documents tab, click Save.

    Copy in json data and click Save in Data Explorer in the Azure portal

  4. Create and save one more document where you insert a unique value for the id property, and change the other properties as you see fit. Your new documents can have any structure you want as Azure Cosmos DB doesn't impose any schema on your data.

Query your data

You can use queries in Data Explorer to retrieve and filter your data.

  1. At the top of the Documents tab in Data Explorer, review the default query SELECT * FROM c. This query retrieves and displays all documents in the collection in ID order.

    Default query in Data Explorer is SELECT * FROM c

  2. To change the query, select Edit Filter, replace the default query with ORDER BY c._ts DESC, and then select Apply Filter.

    Change the default query by adding ORDER BY c._ts DESC and clicking Apply Filter

    The modified query displays the documents in descending order based on their time stamp, so now your second document is listed first.

    Changed query to ORDER BY c._ts DESC and clicking Apply Filter

If you're familiar with SQL syntax, you can enter any supported SQL queries in the query predicate box. You can also use Data Explorer to create stored procedures, UDFs, and triggers for server-side business logic.

Data Explorer provides easy Azure portal access to all of the built-in programmatic data access features available in the APIs. You also use the portal to scale throughput, get keys and connection strings, and review metrics and SLAs for your Azure Cosmos DB account.

Clone the sample application

Now let's switch to working with code. Let's clone a SQL API app from GitHub, set the connection string, and run it. You'll see how easy it is to work with data programmatically.

  1. Run the following command to clone the sample repository. This command creates a copy of the sample app on your computer.

    git clone https://github.com/Azure-Samples/azure-cosmos-db-sql-api-async-java-getting-started
    

Review the code

This step is optional. If you're interested in learning how the database resources are created in the code, you can review the following snippets. Otherwise, you can skip ahead to Run the app .

  • AsyncDocumentClient initialization. The AsyncDocumentClient provides client-side logical representation for the Azure Cosmos database service. This client is used to configure and execute requests against the service.

    client = new AsyncDocumentClient.Builder()
             .withServiceEndpoint(YOUR_COSMOS_DB_ENDPOINT)
             .withMasterKeyOrResourceToken(YOUR_COSMOS_DB_MASTER_KEY)
             .withConnectionPolicy(ConnectionPolicy.GetDefault())
             .withConsistencyLevel(ConsistencyLevel.Eventual)
             .build();
    
  • Database creation.

    Database databaseDefinition = new Database();
    databaseDefinition.setId(databaseName);
    
    client.createDatabase(databaseDefinition, null)
            .toCompletable()
            .await();
    
  • DocumentCollection creation.

    DocumentCollection collectionDefinition = new DocumentCollection();
    collectionDefinition.setId(collectionName);
    
    //...
    
    client.createCollection(databaseLink, collectionDefinition, requestOptions)
            .toCompletable()
            .await();
    
  • Document creation by using the createDocument method.

    // Any Java object within your code
    // can be serialized into JSON and written to Azure Cosmos DB
    Family andersenFamily = new Family();
    andersenFamily.setId("Andersen.1");
    andersenFamily.setLastName("Andersen");
    // More properties
    
    String collectionLink = String.format("/dbs/%s/colls/%s", databaseName, collectionName);
    client.createDocument(collectionLink, family, null, true)
            .toCompletable()
            .await();
    
    
  • SQL queries over JSON are performed using the queryDocuments method.

    FeedOptions queryOptions = new FeedOptions();
    queryOptions.setPageSize(-1);
    queryOptions.setEnableCrossPartitionQuery(true);
    queryOptions.setMaxDegreeOfParallelism(-1);
    
    String collectionLink = String.format("/dbs/%s/colls/%s",
            databaseName,
            collectionName);
    Iterator<FeedResponse<Document>> it = client.queryDocuments(
            collectionLink,
            "SELECT * FROM Family WHERE Family.lastName = 'Andersen'",
            queryOptions).toBlocking().getIterator();
    
    System.out.println("Running SQL query...");
    while (it.hasNext()) {
        FeedResponse<Document> page = it.next();
        System.out.println(
                String.format("\tRead a page of results with %d items",
                        page.getResults().size()));
        for (Document doc : page.getResults()) {
            System.out.println(String.format("\t doc %s", doc));
        }
    }
    

Run the app

Now go back to the Azure portal to get your connection string information and launch the app with your endpoint information. This enables your app to communicate with your hosted database.

  1. In the git terminal window, cd to the sample code folder.

    cd azure-cosmos-db-sql-api-async-java-getting-started/azure-cosmosdb-get-started
    
  2. In the git terminal window, use the following command to install the required Java packages.

    mvn package
    
  3. In the git terminal window, use the following command to start the Java application (replace YOUR_COSMOS_DB_HOSTNAME with the quoted URI value from the portal, and replace YOUR_COSMOS_DB_MASTER_KEY with the quoted primary key from portal)

    mvn exec:java -DACCOUNT_HOST=YOUR_COSMOS_DB_HOSTNAME -DACCOUNT_KEY=YOUR_COSMOS_DB_MASTER_KEY
    
    

    The terminal window displays a notification that the FamilyDB database was created.

  4. Press a key to create the database, and then another key to create the collection.

    Switch back to Data Explorer in your browser to see that it now contains a FamilyDB database, and FamilyCollection collection.

  5. Switch to the console window and press a key to create the first document, and then another key to create the second document. Then switch back to Data Explorer to view them.

  6. Press a key to run a query and see the output in the console window.

  7. The app doesn't delete the created resources. Switch back to the portal to clean up the resources. from your account so that you don't incur charges.

    Console output

Review SLAs in the Azure portal

The Azure portal monitors your Cosmos DB account throughput, storage, availability, latency, and consistency. Charts for metrics associated with an Azure Cosmos DB Service Level Agreement (SLA) show the SLA value compared to actual performance. This suite of metrics makes monitoring your SLAs transparent.

To review metrics and SLAs:

  1. Select Metrics in your Cosmos DB account's navigation menu.

  2. Select a tab such as Latency, and select a timeframe on the right. Compare the Actual and SLA lines on the charts.

    Azure Cosmos DB metrics suite

  3. Review the metrics on the other tabs.

Clean up resources

When you're done with your web app and Azure Cosmos DB account, you can delete the Azure resources you created so you don't incur more charges. To delete the resources:

  1. In the Azure portal, select Resource groups on the far left. If the left menu is collapsed, select Expand button to expand it.

  2. Select the resource group you created for this quickstart.

    Metrics in the Azure portal

  3. In the new window, select Delete resource group.

    Metrics in the Azure portal

  4. In the next window, type the name of the resource group to delete, and then select Delete.

Next steps

In this quickstart, you've learned how to create an Azure Cosmos account, document database, and container using the Data Explorer, and run an app to do the same thing programmatically. You can now import additional data into your Azure Cosmos container.