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2026-04-17 10:11:47 -04:00

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Java SDK Versioning

For conceptual overview and guidance on choosing an approach, see references/core/versioning.md.

Patching API

Workflow.getVersion()

Workflow.getVersion(String changeId, int minSupported, int maxSupported) returns the version to use for a given change:

import io.temporal.workflow.Workflow;

@WorkflowInterface
public interface ShippingWorkflow {
    @WorkflowMethod
    void run();
}

public class ShippingWorkflowImpl implements ShippingWorkflow {
    @Override
    public void run() {
        int version = Workflow.getVersion(
            "send-email-instead-of-fax",
            Workflow.DEFAULT_VERSION,  // minSupported (no change)
            1                          // maxSupported (current version)
        );

        if (version == 1) {
            // New code path
            Workflow.newActivityStub(MyActivities.class, options).sendEmail();
        } else {
            // Old code path (for replay of existing workflows)
            Workflow.newActivityStub(MyActivities.class, options).sendFax();
        }
    }
}

How it works:

  • For new executions: returns maxSupported and records a marker in history
  • For replay with the marker: returns the recorded version
  • For replay without the marker: returns DEFAULT_VERSION (-1)

Three-Step Patching Process

Step 1: Patch in New Code

Add the version check with both old and new code paths:

public class OrderWorkflowImpl implements OrderWorkflow {
    @Override
    public String run(Order order) {
        int version = Workflow.getVersion(
            "add-fraud-check",
            Workflow.DEFAULT_VERSION,
            1);

        if (version >= 1) {
            activities.checkFraud(order);
        }

        return activities.processPayment(order);
    }
}

Step 2: Remove Old Code Path

Once all pre-patch Workflow Executions have completed, remove the old branch and set minSupported to 1:

public class OrderWorkflowImpl implements OrderWorkflow {
    @Override
    public String run(Order order) {
        Workflow.getVersion("add-fraud-check", 1, 1);

        activities.checkFraud(order);
        return activities.processPayment(order);
    }
}

Step 3: Remove the Patch

After all workflows with the patch marker have completed, remove the getVersion call entirely:

public class OrderWorkflowImpl implements OrderWorkflow {
    @Override
    public String run(Order order) {
        activities.checkFraud(order);
        return activities.processPayment(order);
    }
}

Recording TemporalChangeVersion Search Attribute

Unlike the Python and TypeScript SDKs, the Java SDK does not automatically record the TemporalChangeVersion search attribute. You must manually upsert it:

import io.temporal.workflow.Workflow;
import io.temporal.common.SearchAttributeKey;
import java.util.List;

public class OrderWorkflowImpl implements OrderWorkflow {
    private static final SearchAttributeKey<List<String>> TEMPORAL_CHANGE_VERSION =
        SearchAttributeKey.forKeywordList("TemporalChangeVersion");

    @Override
    public String run(Order order) {
        int version = Workflow.getVersion("add-fraud-check", Workflow.DEFAULT_VERSION, 1);

        // Manually record for query filtering
        Workflow.upsertTypedSearchAttributes(
            TEMPORAL_CHANGE_VERSION.valueSet(List.of("add-fraud-check-1")));

        if (version >= 1) {
            activities.checkFraud(order);
        }
        return activities.processPayment(order);
    }
}

Query with:

temporal workflow list --query \
  'TemporalChangeVersion = "add-fraud-check-1" AND ExecutionStatus = "Running"'

Workflow Type Versioning

For incompatible changes, create a new Workflow Type:

@WorkflowInterface
public interface PizzaWorkflow {
    @WorkflowMethod
    String run(PizzaOrder order);
}

// Original implementation
public class PizzaWorkflowImpl implements PizzaWorkflow {
    @Override
    public String run(PizzaOrder order) {
        return processOrderV1(order);
    }
}

// New workflow type for incompatible changes
@WorkflowInterface
public interface PizzaWorkflowV2 {
    @WorkflowMethod
    String run(PizzaOrder order);
}

public class PizzaWorkflowV2Impl implements PizzaWorkflowV2 {
    @Override
    public String run(PizzaOrder order) {
        return processOrderV2(order);
    }
}

Register both with the Worker:

worker.registerWorkflowImplementationTypes(
    PizzaWorkflowImpl.class,
    PizzaWorkflowV2Impl.class);

Start new workflows with the new type:

PizzaWorkflowV2 workflow = client.newWorkflowStub(
    PizzaWorkflowV2.class,
    WorkflowOptions.newBuilder()
        .setTaskQueue("pizza-task-queue")
        .build());
workflow.run(order);

Check for open executions before removing the old type:

temporal workflow list --query 'WorkflowType = "PizzaWorkflow" AND ExecutionStatus = "Running"'

Worker Versioning

Worker Versioning manages versions at the deployment level. Available since Java SDK v1.29.

Key Concepts

  • Worker Deployment: A logical group of Workers processing the same Task Queue, identified by a deployment name (e.g., "order-service").
  • Worker Deployment Version: A specific version within a deployment, identified by the combination of deployment name and Build ID (e.g., "order-service:v1.0.0"). Each version corresponds to a particular code revision.

Configuring Workers

import io.temporal.worker.Worker;
import io.temporal.worker.WorkerFactory;
import io.temporal.worker.WorkerOptions;
import io.temporal.worker.WorkerDeploymentOptions;
import io.temporal.worker.WorkerDeploymentVersion;

WorkerDeploymentVersion version = WorkerDeploymentVersion.newBuilder()
    .setDeploymentName("order-service")
    .setBuildId("v1.0.0")  // or git commit hash
    .build();

WorkerDeploymentOptions deploymentOptions = WorkerDeploymentOptions.newBuilder()
    .setVersion(version)
    .setUseWorkerVersioning(true)
    .build();

WorkerFactory factory = WorkerFactory.newInstance(client);
Worker worker = factory.newWorker(
    "my-task-queue",
    WorkerOptions.newBuilder()
        .setDeploymentOptions(deploymentOptions)
        .build());

worker.registerWorkflowImplementationTypes(MyWorkflowImpl.class);
worker.registerActivitiesImplementations(new MyActivitiesImpl());
factory.start();

PINNED vs AUTO_UPGRADE Behaviors

Set the versioning behavior on the workflow definition:

import io.temporal.workflow.VersioningBehavior;
import io.temporal.workflow.Workflow;

public class MyWorkflowImpl implements MyWorkflow {
    @Override
    public String run(String input) {
        Workflow.setVersioningBehavior(VersioningBehavior.PINNED);
        // ... workflow logic
    }
}

PINNED: Workflow stays on the Worker version that started it. Use for short-running workflows or when consistency within a single execution is critical. New workflows start on the current version; existing ones stay put.

AUTO_UPGRADE: Workflow moves to the latest Worker version on the next Workflow Task. Use for long-running workflows that need bug fixes or feature updates. Combine with Workflow.getVersion() patching to handle version transitions safely.

Deployment Strategies

Blue-Green: Run two deployment versions simultaneously. Set the new version as the current deployment. PINNED workflows finish on the old version; new workflows start on the new version. Drain the old version once all its workflows complete.

Rainbow: Run multiple versions concurrently for gradual rollouts. Each version handles its own workflows. Useful when you have many long-running PINNED workflows across several code revisions.

Querying Workflows by Worker Version

# List workflows running on a specific version
temporal workflow list --query \
  'TemporalWorkerDeploymentVersion = "order-service:v1.0.0" AND ExecutionStatus = "Running"'

# Count workflows per version to monitor drain progress
temporal workflow count --query \
  'TemporalWorkerDeploymentVersion = "order-service:v1.0.0" AND ExecutionStatus = "Running"'

Best Practices

  1. Check for open executions before removing old code paths
  2. Use descriptive change IDs that explain the change (e.g., "add-fraud-check" not "patch-1")
  3. Deploy patches incrementally: patch, remove old path, remove getVersion
  4. Manually upsert TemporalChangeVersion search attribute when using getVersion if you need query filtering
  5. Use PINNED for short workflows to simplify version management
  6. Use AUTO_UPGRADE with patching for long-running workflows that need updates
  7. Generate Build IDs from code (git hash) to ensure changes produce new versions