Azure Batch SDK for Java

Client library for running large-scale parallel and high-performance computing (HPC) batch jobs in Azure.

Installation

<dependency>
    <groupId>com.azure</groupId>
    <artifactId>azure-compute-batch</artifactId>
    <version>1.0.0-beta.5</version>
</dependency>

Prerequisites

• Azure Batch account
• Pool configured with compute nodes
• Azure subscription

Environment Variables

AZURE_BATCH_ENDPOINT=https://<account>.<region>.batch.azure.com  # Required for all auth methods
AZURE_BATCH_ACCOUNT=<account-name>  # Only required for shared key auth
AZURE_BATCH_ACCESS_KEY=<account-key>  # Only required for shared key auth
AZURE_TOKEN_CREDENTIALS=prod  # Required only if DefaultAzureCredential is used in production

Client Creation

With Microsoft Entra ID (Recommended)

import com.azure.compute.batch.BatchClient;
import com.azure.compute.batch.BatchClientBuilder;
import com.azure.core.credential.TokenCredential;
import com.azure.identity.AzureIdentityEnvVars;
import com.azure.identity.DefaultAzureCredentialBuilder;
import com.azure.identity.ManagedIdentityCredentialBuilder;

// Local dev: DefaultAzureCredential. Production: set AZURE_TOKEN_CREDENTIALS=prod or AZURE_TOKEN_CREDENTIALS=<specific_credential>
TokenCredential credential = new DefaultAzureCredentialBuilder()
    .requireEnvVars(AzureIdentityEnvVars.AZURE_TOKEN_CREDENTIALS)
    .build();
// Or use a specific credential directly in production:
// See https://learn.microsoft.com/java/api/overview/azure/identity-readme?view=azure-java-stable#credential-classes
// TokenCredential credential = new ManagedIdentityCredentialBuilder().build();

BatchClient batchClient = new BatchClientBuilder()
    .credential(credential)
    .endpoint(System.getenv("AZURE_BATCH_ENDPOINT"))
    .buildClient();

Async Client

import com.azure.compute.batch.BatchAsyncClient;

BatchAsyncClient batchAsyncClient = new BatchClientBuilder()
    .credential(credential)
    .endpoint(System.getenv("AZURE_BATCH_ENDPOINT"))
    .buildAsyncClient();

With Shared Key Credentials

import com.azure.core.credential.AzureNamedKeyCredential;

String accountName = System.getenv("AZURE_BATCH_ACCOUNT");
String accountKey = System.getenv("AZURE_BATCH_ACCESS_KEY");
AzureNamedKeyCredential sharedKeyCreds = new AzureNamedKeyCredential(accountName, accountKey);

BatchClient batchClient = new BatchClientBuilder()
    .credential(sharedKeyCreds)
    .endpoint(System.getenv("AZURE_BATCH_ENDPOINT"))
    .buildClient();

Key Concepts

Pool Operations

Create Pool

import com.azure.compute.batch.models.*;

batchClient.createPool(new BatchPoolCreateParameters("myPoolId", "STANDARD_DC2s_V2")
    .setVirtualMachineConfiguration(
        new VirtualMachineConfiguration(
            new BatchVmImageReference()
                .setPublisher("Canonical")
                .setOffer("UbuntuServer")
                .setSku("22_04-lts")
                .setVersion("latest"),
            "batch.node.ubuntu 22.04"))
    .setTargetDedicatedNodes(2)
    .setTargetLowPriorityNodes(0), null);

Get Pool

BatchPool pool = batchClient.getPool("myPoolId");
System.out.println("Pool state: " + pool.getState());
System.out.println("Current dedicated nodes: " + pool.getCurrentDedicatedNodes());

List Pools

import com.azure.core.http.rest.PagedIterable;

PagedIterable<BatchPool> pools = batchClient.listPools();
for (BatchPool pool : pools) {
    System.out.println("Pool: " + pool.getId() + ", State: " + pool.getState());
}

Resize Pool

import com.azure.core.util.polling.SyncPoller;

BatchPoolResizeParameters resizeParams = new BatchPoolResizeParameters()
    .setTargetDedicatedNodes(4)
    .setTargetLowPriorityNodes(2);

SyncPoller<BatchPool, BatchPool> poller = batchClient.beginResizePool("myPoolId", resizeParams);
poller.waitForCompletion();
BatchPool resizedPool = poller.getFinalResult();

Enable AutoScale

BatchPoolEnableAutoScaleParameters autoScaleParams = new BatchPoolEnableAutoScaleParameters()
    .setAutoScaleEvaluationInterval(Duration.ofMinutes(5))
    .setAutoScaleFormula("$TargetDedicatedNodes = min(10, $PendingTasks.GetSample(TimeInterval_Minute * 5));");

batchClient.enablePoolAutoScale("myPoolId", autoScaleParams);

Delete Pool

SyncPoller<BatchPool, Void> deletePoller = batchClient.beginDeletePool("myPoolId");
deletePoller.waitForCompletion();

Job Operations

Create Job

batchClient.createJob(
    new BatchJobCreateParameters("myJobId", new BatchPoolInfo().setPoolId("myPoolId"))
        .setPriority(100)
        .setConstraints(new BatchJobConstraints()
            .setMaxWallClockTime(Duration.ofHours(24))
            .setMaxTaskRetryCount(3)),
    null);

Get Job

BatchJob job = batchClient.getJob("myJobId", null, null);
System.out.println("Job state: " + job.getState());

List Jobs

PagedIterable<BatchJob> jobs = batchClient.listJobs(new BatchJobsListOptions());
for (BatchJob job : jobs) {
    System.out.println("Job: " + job.getId() + ", State: " + job.getState());
}

Get Task Counts

BatchTaskCountsResult counts = batchClient.getJobTaskCounts("myJobId");
System.out.println("Active: " + counts.getTaskCounts().getActive());
System.out.println("Running: " + counts.getTaskCounts().getRunning());
System.out.println("Completed: " + counts.getTaskCounts().getCompleted());

Terminate Job

BatchJobTerminateParameters terminateParams = new BatchJobTerminateParameters()
    .setTerminationReason("Manual termination");
BatchJobTerminateOptions options = new BatchJobTerminateOptions().setParameters(terminateParams);

SyncPoller<BatchJob, BatchJob> poller = batchClient.beginTerminateJob("myJobId", options, null);
poller.waitForCompletion();

Delete Job

SyncPoller<BatchJob, Void> deletePoller = batchClient.beginDeleteJob("myJobId");
deletePoller.waitForCompletion();

Task Operations

Create Single Task

BatchTaskCreateParameters task = new BatchTaskCreateParameters("task1", "echo 'Hello World'");
batchClient.createTask("myJobId", task);

Create Task with Exit Conditions

batchClient.createTask("myJobId", new BatchTaskCreateParameters("task2", "cmd /c exit 3")
    .setExitConditions(new ExitConditions()
        .setExitCodeRanges(Arrays.asList(
            new ExitCodeRangeMapping(2, 4, 
                new ExitOptions().setJobAction(BatchJobActionKind.TERMINATE)))))
    .setUserIdentity(new UserIdentity()
        .setAutoUser(new AutoUserSpecification()
            .setScope(AutoUserScope.TASK)
            .setElevationLevel(ElevationLevel.NON_ADMIN))),
    null);

Create Task Collection (up to 100)

List<BatchTaskCreateParameters> taskList = Arrays.asList(
    new BatchTaskCreateParameters("task1", "echo Task 1"),
    new BatchTaskCreateParameters("task2", "echo Task 2"),
    new BatchTaskCreateParameters("task3", "echo Task 3")
);
BatchTaskGroup taskGroup = new BatchTaskGroup(taskList);
BatchCreateTaskCollectionResult result = batchClient.createTaskCollection("myJobId", taskGroup);

Create Many Tasks (no limit)

List<BatchTaskCreateParameters> tasks = new ArrayList<>();
for (int i = 0; i < 1000; i++) {
    tasks.add(new BatchTaskCreateParameters("task" + i, "echo Task " + i));
}
batchClient.createTasks("myJobId", tasks);

Get Task

BatchTask task = batchClient.getTask("myJobId", "task1");
System.out.println("Task state: " + task.getState());
System.out.println("Exit code: " + task.getExecutionInfo().getExitCode());

List Tasks

PagedIterable<BatchTask> tasks = batchClient.listTasks("myJobId");
for (BatchTask task : tasks) {
    System.out.println("Task: " + task.getId() + ", State: " + task.getState());
}

Get Task Output

import com.azure.core.util.BinaryData;
import java.nio.charset.StandardCharsets;

BinaryData stdout = batchClient.getTaskFile("myJobId", "task1", "stdout.txt");
System.out.println(new String(stdout.toBytes(), StandardCharsets.UTF_8));

Terminate Task

batchClient.terminateTask("myJobId", "task1", null, null);

Node Operations

List Nodes

PagedIterable<BatchNode> nodes = batchClient.listNodes("myPoolId", new BatchNodesListOptions());
for (BatchNode node : nodes) {
    System.out.println("Node: " + node.getId() + ", State: " + node.getState());
}

Reboot Node

SyncPoller<BatchNode, BatchNode> rebootPoller = batchClient.beginRebootNode("myPoolId", "nodeId");
rebootPoller.waitForCompletion();

Get Remote Login Settings

BatchNodeRemoteLoginSettings settings = batchClient.getNodeRemoteLoginSettings("myPoolId", "nodeId");
System.out.println("IP: " + settings.getRemoteLoginIpAddress());
System.out.println("Port: " + settings.getRemoteLoginPort());

Job Schedule Operations

Create Job Schedule

batchClient.createJobSchedule(new BatchJobScheduleCreateParameters("myScheduleId",
    new BatchJobScheduleConfiguration()
        .setRecurrenceInterval(Duration.ofHours(6))
        .setDoNotRunUntil(OffsetDateTime.now().plusDays(1)),
    new BatchJobSpecification(new BatchPoolInfo().setPoolId("myPoolId"))
        .setPriority(50)),
    null);

Get Job Schedule

BatchJobSchedule schedule = batchClient.getJobSchedule("myScheduleId");
System.out.println("Schedule state: " + schedule.getState());

Error Handling

import com.azure.compute.batch.models.BatchErrorException;
import com.azure.compute.batch.models.BatchError;

try {
    batchClient.getPool("nonexistent-pool");
} catch (BatchErrorException e) {
    BatchError error = e.getValue();
    System.err.println("Error code: " + error.getCode());
    System.err.println("Message: " + error.getMessage().getValue());
    
    if ("PoolNotFound".equals(error.getCode())) {
        System.err.println("The specified pool does not exist.");
    }
}

Best Practices

1. Use Entra ID — Preferred over shared key for authentication
2. Use management SDK for pools — azure-resourcemanager-batch supports managed identities
3. Batch task creation — Use createTaskCollection or createTasks for multiple tasks
4. Handle LRO properly — Pool resize, delete operations are long-running
5. Monitor task counts — Use getJobTaskCounts to track progress
6. Set constraints — Configure maxWallClockTime and maxTaskRetryCount
7. Use low-priority nodes — Cost savings for fault-tolerant workloads
8. Enable autoscale — Dynamically adjust pool size based on workload

Reference Links