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The type of a component refers to a declaration either in the type section of the current YAML file or in a YAML file included (directly or indirectly) included in in the imports section. Type declarations ultimately refer to Java classes, and are covered in associate each component type with a Java class, and will be covered in a later tutorial.
Finally, each component has a set of properties that represents its configuration in the current workflow.
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The final component of in hello.yaml is identifies identified as HelloWorldWorkflow:
- id: HelloWorldWorkflow type: Workflow properties: actors: - !ref GreetingSource - !ref GreetingPrinter parameters: greeting: actor: !ref GreetingSource parameter: value
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