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Your Implementation must extend https://flexagon.com/function-sdk/7.0/flexagon/fd/model/integration/its/api/IssueTrackingSystem.html in order to be used by FlexDeploy. If you are not going to allow calling a method, you can leave the body blank, or throw an error in the body, but the method must be defined. If you choose to make a Java implementation, your IDE will verify that you have implemented all the required methods. If you choose the Groovy implementation, then the FlexDeploy UI will validate that your class contains the necessary methods. Groovy implementations can be used even with 3rd party jars that you place in libext, and allow for easier iterations. The advantage of a Java implementation is a potentially tighter integration with source control.
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