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Get started with cloud development using Java on Azure

This article walks you through setting up a development environment for Azure development in Java. You'll then create some Azure resources and connect to them to do some basic tasks, like uploading a file or deploying a web application. When you're finished, you'll be ready to start using Azure services in your own Java applications.

Prerequisites

Set up authentication

Your Java application needs read and create permissions in your Azure subscription to run the sample code in this tutorial. Create a service principal, and configure your application to run with its credentials. Service principals provide a way to create a noninteractive account associated with your identity to which you grant only the privileges your app needs to run.

Create a service principal by using the Azure CLI 2.0, and capture the output:

az ad sp create-for-rbac \
    --name AzureJavaTest \
    --role Contributor \
    --scopes /subscriptions/<your-subscription-ID>

This command gives you a reply in the following format:

{
  "appId": "a487e0c1-82af-47d9-9a0b-af184eb87646d",
  "displayName": "AzureJavaTest",
  "name": "http://AzureJavaTest",
  "password": "aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa",
  "tenant": "tttttttt-tttt-tttt-tttt-tttttttttttt"
}

Next, configure the environment variables:

  • AZURE_SUBSCRIPTION_ID: Use the id value from az account show in the Azure CLI 2.0.
  • AZURE_CLIENT_ID: Use the appId value from the output taken from a service principal output.
  • AZURE_CLIENT_SECRET: Use the password value from the service principal output.
  • AZURE_TENANT_ID: Use the tenant value from the service principal output.

For more authentication options, see the Azure Identity client library for Java.

Tooling

Create a new Maven project

Note

This article uses the Maven build tool to build and run the sample code. Other build tools, such as Gradle, also work with the Azure SDK for Java.

Create a Maven project from the command line in a new directory on your system.

mkdir java-azure-test
cd java-azure-test
mvn archetype:generate -DgroupId=com.fabrikam -DartifactId=AzureApp \
-DarchetypeArtifactId=maven-archetype-quickstart -DinteractiveMode=false

This step creates a basic Maven project under the testAzureApp directory. Add the following entries into the project's pom.xml file to import the libraries used in the sample code in this tutorial.

<dependency>
  <groupId>com.azure</groupId>
  <artifactId>azure-identity</artifactId>
  <version>1.3.2</version>
</dependency>
<dependency>
  <groupId>com.azure.resourcemanager</groupId>
  <artifactId>azure-resourcemanager</artifactId>
  <version>2.6.0</version>
</dependency>
<dependency>
  <groupId>com.azure</groupId>
  <artifactId>azure-storage-blob</artifactId>
  <version>12.8.0</version>
</dependency>
<dependency>
  <groupId>com.microsoft.sqlserver</groupId>
  <artifactId>mssql-jdbc</artifactId>
  <version>6.2.1.jre8</version>
</dependency>
<dependency>
  <groupId>org.slf4j</groupId>
  <artifactId>slf4j-simple</artifactId>
  <version>1.7.33</version>
</dependency>

Add a build entry under the top-level project element to use the maven-exec-plugin to run the samples. maven-compiler-plugin is used to configure the source code and generated classes for Java 8.

<build>
  <plugins>
    <plugin>
      <groupId>org.codehaus.mojo</groupId>
      <artifactId>exec-maven-plugin</artifactId>
      <version>3.0.0</version>
      <configuration>
        <mainClass>com.fabrikam.App</mainClass>
      </configuration>
    </plugin>
    <plugin>
      <groupId>org.apache.maven.plugins</groupId>
      <artifactId>maven-compiler-plugin</artifactId>
      <version>3.8.1</version>
      <configuration>
        <source>1.8</source>
        <target>1.8</target>
      </configuration>
    </plugin>
  </plugins>
</build>

Create a Linux virtual machine

Create a new file named App.java in the project's src/main/java/com/fabrikam directory, and paste in the following block of code. Update the userName and sshKey variables with real values for your machine. The code creates a new Linux virtual machine (VM) with the name testLinuxVM in the resource group sampleResourceGroup running in the US East Azure region.

package com.fabrikam;

import com.azure.core.credential.TokenCredential;
import com.azure.core.http.policy.HttpLogDetailLevel;
import com.azure.core.management.AzureEnvironment;
import com.azure.core.management.Region;
import com.azure.core.management.profile.AzureProfile;
import com.azure.identity.AzureAuthorityHosts;
import com.azure.identity.DefaultAzureCredentialBuilder;
import com.azure.resourcemanager.AzureResourceManager;
import com.azure.resourcemanager.compute.models.KnownLinuxVirtualMachineImage;
import com.azure.resourcemanager.compute.models.VirtualMachine;
import com.azure.resourcemanager.compute.models.VirtualMachineSizeTypes;

public class App {

    public static void main(String[] args) {

        final String userName = "YOUR_VM_USERNAME";
        final String sshKey = "YOUR_PUBLIC_SSH_KEY";

        try {
            TokenCredential credential = new DefaultAzureCredentialBuilder()
                    .authorityHost(AzureAuthorityHosts.AZURE_PUBLIC_CLOUD)
                    .build();

            // If you don't set the tenant ID and subscription ID via environment variables,
            // change to create the Azure profile with tenantId, subscriptionId, and Azure environment.
            AzureProfile profile = new AzureProfile(AzureEnvironment.AZURE);

            AzureResourceManager azureResourceManager = AzureResourceManager.configure()
                    .withLogLevel(HttpLogDetailLevel.BASIC)
                    .authenticate(credential, profile)
                    .withDefaultSubscription();

            // Create an Ubuntu virtual machine in a new resource group.
            VirtualMachine linuxVM = azureResourceManager.virtualMachines().define("testLinuxVM")
                    .withRegion(Region.US_EAST)
                    .withNewResourceGroup("sampleVmResourceGroup")
                    .withNewPrimaryNetwork("10.0.0.0/24")
                    .withPrimaryPrivateIPAddressDynamic()
                    .withoutPrimaryPublicIPAddress()
                    .withPopularLinuxImage(KnownLinuxVirtualMachineImage.UBUNTU_SERVER_18_04_LTS)
                    .withRootUsername(userName)
                    .withSsh(sshKey)
                    .withSize(VirtualMachineSizeTypes.STANDARD_D3_V2)
                    .create();

        } catch (Exception e) {
            System.out.println(e.getMessage());
            e.printStackTrace();
        }
    }
}

Run the sample from the command line.

mvn compile exec:java

You'll see some REST requests and responses in the console as the SDK makes the underlying calls to the Azure REST API to configure the VM and its resources. After the program finishes, verify the VM in your subscription with the Azure CLI 2.0.

az vm list --resource-group sampleVmResourceGroup

After you've verified that the code worked, use the CLI to delete the VM and its resources.

az group delete --name sampleVmResourceGroup

Deploy a web app from a GitHub repo

Replace the main method in App.java with the following one. Update the appName variable to a unique value before you run the code. This code deploys a web application from the master branch in a public GitHub repo into a new Azure App Service Web App running in the free pricing tier.

    public static void main(String[] args) {
        try {

            final String appName = "YOUR_APP_NAME";

            TokenCredential credential = new DefaultAzureCredentialBuilder()
                    .authorityHost(AzureAuthorityHosts.AZURE_PUBLIC_CLOUD)
                    .build();

            // If you don't set the tenant ID and subscription ID via environment variables,
            // change to create the Azure profile with tenantId, subscriptionId, and Azure environment.
            AzureProfile profile = new AzureProfile(AzureEnvironment.AZURE);
            
            AzureResourceManager azureResourceManager = AzureResourceManager.configure()
                    .withLogLevel(HttpLogDetailLevel.BASIC)
                    .authenticate(credential, profile)
                    .withDefaultSubscription();

            WebApp app = azureResourceManager.webApps().define(appName)
                    .withRegion(Region.US_WEST2)
                    .withNewResourceGroup("sampleWebResourceGroup")
                    .withNewWindowsPlan(PricingTier.FREE_F1)
                    .defineSourceControl()
                    .withPublicGitRepository(
                            "https://github.com/Azure-Samples/app-service-web-java-get-started")
                    .withBranch("master")
                    .attach()
                    .create();

        } catch (Exception e) {
            System.out.println(e.getMessage());
            e.printStackTrace();
        }
    }

Run the code as before using Maven.

mvn clean compile exec:java

Open a browser pointed to the application by using the CLI.

az webapp browse --resource-group sampleWebResourceGroup --name YOUR_APP_NAME

Remove the web app and plan from your subscription after you've verified the deployment.

az group delete --name sampleWebResourceGroup

Connect to an Azure SQL database

Replace the current main method in App.java with the following code. Set real values for the variables. This code creates a new SQL database with a firewall rule that allows remote access. Then the code connects to it by using the SQL Database JBDC driver.

    public static void main(String args[]) {
        // Create the db using the management libraries.
        try {
            TokenCredential credential = new DefaultAzureCredentialBuilder()
                    .authorityHost(AzureAuthorityHosts.AZURE_PUBLIC_CLOUD)
                    .build();

            // If you don't set the tenant ID and subscription ID via environment variables,
            // change to create the Azure profile with tenantId, subscriptionId, and Azure environment.
            AzureProfile profile = new AzureProfile(AzureEnvironment.AZURE);

            AzureResourceManager azureResourceManager = AzureResourceManager.configure()
                    .withLogLevel(HttpLogDetailLevel.BASIC)
                    .authenticate(credential, profile)
                    .withDefaultSubscription();

            final String adminUser = "YOUR_USERNAME_HERE";
            final String sqlServerName = "YOUR_SERVER_NAME_HERE";
            final String sqlDbName = "YOUR_DB_NAME_HERE";
            final String dbPassword = "YOUR_PASSWORD_HERE";
            final String firewallRuleName = "YOUR_RULE_NAME_HERE";

            SqlServer sampleSQLServer = azureResourceManager.sqlServers().define(sqlServerName)
                    .withRegion(Region.US_EAST)
                    .withNewResourceGroup("sampleSqlResourceGroup")
                    .withAdministratorLogin(adminUser)
                    .withAdministratorPassword(dbPassword)
                    .defineFirewallRule(firewallRuleName)
                        .withIpAddressRange("0.0.0.0","255.255.255.255")
                        .attach()
                    .create();

            SqlDatabase sampleSQLDb = sampleSQLServer.databases().define(sqlDbName).create();

            // Assemble the connection string to the database.
            final String domain = sampleSQLServer.fullyQualifiedDomainName();
            String url = "jdbc:sqlserver://"+ domain + ":1433;" +
                    "database=" + sqlDbName +";" +
                    "user=" + adminUser+ "@" + sqlServerName + ";" +
                    "password=" + dbPassword + ";" +
                    "encrypt=true;trustServerCertificate=false;hostNameInCertificate=*.database.windows.net;loginTimeout=30;";

            // Connect to the database, create a table, and insert an entry into it.
            try (Connection conn = DriverManager.getConnection(url)) {
                String createTable = "CREATE TABLE CLOUD (name varchar(255), code int);";
                String insertValues = "INSERT INTO CLOUD (name, code) VALUES ('Azure', 1);";
                String selectValues = "SELECT * FROM CLOUD";
                try (Statement createStatement = conn.createStatement()) {
                    createStatement.execute(createTable);
                }
                try (Statement insertStatement = conn.createStatement()) {
                    insertStatement.execute(insertValues);
                }
                try (Statement selectStatement = conn.createStatement();
                     ResultSet rst = selectStatement.executeQuery(selectValues)) {
                    while (rst.next()) {
                        System.out.println(rst.getString(1) + " " + rst.getString(2));
                    }
                }
            }
        } catch (Exception e) {
            System.out.println(e.getMessage());
            System.out.println(e.getStackTrace().toString());
        }
    }

Run the sample from the command line.

mvn clean compile exec:java

Then clean up the resources by using the CLI.

az group delete --name sampleSqlResourceGroup

Write a blob into a new storage account

Replace the current main method in App.java with the following code. This code creates an Azure storage account. Then the code uses the Azure Storage libraries for Java to create a new text file in the cloud.

    public static void main(String[] args) {

        try {
            TokenCredential tokenCredential = new DefaultAzureCredentialBuilder()
                    .authorityHost(AzureAuthorityHosts.AZURE_PUBLIC_CLOUD)
                    .build();

            // If you don't set the tenant ID and subscription ID via environment variables,
            // change to create the Azure profile with tenantId, subscriptionId, and Azure environment.
            AzureProfile profile = new AzureProfile(AzureEnvironment.AZURE);

            AzureResourceManager azureResourceManager = AzureResourceManager.configure()
                    .withLogLevel(HttpLogDetailLevel.BASIC)
                    .authenticate(tokenCredential, profile)
                    .withDefaultSubscription();

            // Create a new storage account.
            String storageAccountName = "YOUR_STORAGE_ACCOUNT_NAME_HERE";
            StorageAccount storage = azureResourceManager.storageAccounts().define(storageAccountName)
                    .withRegion(Region.US_WEST2)
                    .withNewResourceGroup("sampleStorageResourceGroup")
                    .create();

            // Create a storage container to hold the file.
            List<StorageAccountKey> keys = storage.getKeys();
            PublicEndpoints endpoints = storage.endPoints();
            String accountName = storage.name();
            String accountKey = keys.get(0).value();
            String endpoint = endpoints.primary().blob();

            StorageSharedKeyCredential credential = new StorageSharedKeyCredential(accountName, accountKey);

            BlobServiceClient storageClient = new BlobServiceClientBuilder()
                    .endpoint(endpoint)
                    .credential(credential)
                    .buildClient();

            // Container name must be lowercase.
            BlobContainerClient blobContainerClient = storageClient.getBlobContainerClient("helloazure");
            blobContainerClient.create();

            // Make the container public.
            blobContainerClient.setAccessPolicy(PublicAccessType.CONTAINER, null);

            // Write a blob to the container.
            String fileName = "helloazure.txt";
            String textNew = "Hello Azure";

            BlobClient blobClient = blobContainerClient.getBlobClient(fileName);
            InputStream is = new ByteArrayInputStream(textNew.getBytes());
            blobClient.upload(is, textNew.length());

        } catch (Exception e) {
            System.out.println(e.getMessage());
            e.printStackTrace();
        }
    }

Run the sample from the command line.

mvn clean compile exec:java

You can browse for the helloazure.txt file in your storage account through the Azure portal or with Azure Storage Explorer.

Clean up the storage account by using the CLI.

az group delete --name sampleStorageResourceGroup

Explore more samples

To learn more about how to use the Azure management libraries for Java to manage resources and automate tasks, see our sample code for virtual machines, web apps, and SQL database.

Reference and release notes

A reference is available for all packages.

Get help and give feedback

Post questions to the community on Stack Overflow. Report bugs and open issues against the Azure SDK for Java in the GitHub repository.