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cclaudio's avatar
cclaudio
New Contributor II
5 years ago
Solved

Issue with Arrays in Downstream Mappers after a Custom Snap Transformation

We built a custom snap that performs a transformation. You will notice in the output of the custom snap in the screenshot below that “medicalEnrollment” is a json array. In a downstream mapper...
pipeline
transform
  • ptaylor's avatar
    ptaylor
    5 years ago

    Thanks. I installed the binary snap pack and set a breakpoint in the Mapper to see the Java types used in the input, which is the output of your snap. I can see that medicalEnrollment is still a HashSet, not an ArrayList:

    I haven’t studied your source code but I can see that you’re still using HashSet in a lot of places. Don’t use that type anywhere in your Document data. It’s not compatible with any of the JSON types. Use ArrayList everywhere you need an array.

ptaylor's avatar
ptaylor
Employee
5 years ago

Thanks. I installed the binary snap pack and set a breakpoint in the Mapper to see the Java types used in the input, which is the output of your snap. I can see that medicalEnrollment is still a HashSet, not an ArrayList:

I haven’t studied your source code but I can see that you’re still using HashSet in a lot of places. Don’t use that type anywhere in your Document data. It’s not compatible with any of the JSON types. Use ArrayList everywhere you need an array.

  • cclaudio's avatar
    cclaudio
    New Contributor II
    5 years ago

    @ptaylor, That was it! We implemented a fix and the downstream mappers are now working properly!