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These samples demonstrate various capabilities of Java Cadence client and server. You can learn more about Cadence at:

• Cadence Service
• Cadence Java Client
• Go Cadence Client

• HelloWorld Samples

  The following samples demonstrate:

  • HelloActivity: a single activity workflow
  • HelloActivityRetry: how to retry an activity
  • HelloAsync: how to call activities asynchronously and wait for them using Promises
  • HelloAsyncLambda: how to run part of a workflow asynchronously in a separate task (thread)
  • HelloAsyncActivityCompletion: an asynchronous activity implementation
  • HelloChild: a child workflow
  • HelloException: exception propagation and wrapping
  • HelloQuery: a query
  • HelloSignal: sending and handling a signal
  • HelloPeriodic: a sample workflow that executes an activity periodically forever
  • HelloSearchAttributes: how to use search attributes
  • HelloCron: a cron workflow

• FileProcessing demonstrates task routing features. The sample workflow downloads a file, processes it, and uploadsthe result to a destination. The first activity can be picked up by any worker. However, the second and third activitiesmust be executed on the same host as the first one.

Run the following commands:

  git clone https://github.com/uber/cadence-java-samples  cd cadence-java-samples

In the IntelliJ user interface, navigate toFile->New->Project from Existing Sources.

Select the cloned directory. In theImport Project page, selectImport project from external model,chooseGradle and then clickNext->Finish.

  ./gradlew build

Run Cadence Server using Docker Compose:

curl -O https://raw.githubusercontent.com/uber/cadence/master/docker/docker-compose.ymldocker-compose up

If this does not work, see the instructions for running Cadence Serverathttps://github.com/uber/cadence/blob/master/README.md.

To register thesamples-domain domain, run the following command once before running any samples:

./gradlew -q execute -PmainClass=com.uber.cadence.samples.common.RegisterDomain

Or using Cadence CLI:

cadence --domain samples-domain domain register

The Cadence Server running in a docker container includes a Web UI.

Connect tohttp://localhost:8088.

Enter thesamples-domain domain. You'll see a "No Results" page. After running any sample, change the filter in thetop right corner from "Open" to "Closed" to see the list of the completed workflows.

Click on aRUN ID of a workflow to see more details about it. Try different view formats to get a different level ofdetails about the execution history.

Command Line Interface Documentation

Each sample has specific requirements for running it. The following sections contain information abouthow to run each of the samples after you've built them using the preceding instructions.

Don't forget to check unit tests found under src/test/java!

To run the hello world samples:

./gradlew -q execute -PmainClass=com.uber.cadence.samples.hello.HelloActivity./gradlew -q execute -PmainClass=com.uber.cadence.samples.hello.HelloActivityRetry./gradlew -q execute -PmainClass=com.uber.cadence.samples.hello.HelloAsync./gradlew -q execute -PmainClass=com.uber.cadence.samples.hello.HelloAsyncActivityCompletion./gradlew -q execute -PmainClass=com.uber.cadence.samples.hello.HelloAsyncLambda./gradlew -q execute -PmainClass=com.uber.cadence.samples.hello.HelloChild./gradlew -q execute -PmainClass=com.uber.cadence.samples.hello.HelloException./gradlew -q execute -PmainClass=com.uber.cadence.samples.hello.HelloPeriodic./gradlew -q execute -PmainClass=com.uber.cadence.samples.hello.HelloQuery./gradlew -q execute -PmainClass=com.uber.cadence.samples.hello.HelloSignal./gradlew -q execute -PmainClass=com.uber.cadence.samples.hello.HelloSearchAttributes./gradlew -q execute -PmainClass=com.uber.cadence.samples.hello.HelloCron

This sample has two executables. Execute each command in a separate terminal window. The first commandruns the worker that hosts the workflow and activities implementation. To demonstrate that activitiesexecute together, we recommend that you run more than one instance of this worker.

./gradlew -q execute -PmainClass=com.uber.cadence.samples.fileprocessing.FileProcessingWorker

The second command starts workflows. Each invocation starts a new workflow execution.

./gradlew -q execute -PmainClass=com.uber.cadence.samples.fileprocessing.FileProcessingStarter

Cadence implementation of theCamunda BPMN trip booking example

Demonstrates Cadence approach to SAGA.

To run:

./gradlew -q execute -PmainClass=com.uber.cadence.samples.bookingsaga.TripBookingSaga

Example of how to start a cadence worker service using Spring Boot Framework

To run:

# Start Cadence Server# see https://github.com/uber/cadence/tree/master/docker# register domain./gradlew -q execute -PmainClass=com.uber.cadence.samples.common.RegisterDomain./gradlew -q execute -PmainClass=com.uber.cadence.samples.spring.CadenceSamplesApplication

Apache 2.0 License, please seeLICENSE for details.