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Remark: This example adds an operator to an existing bundle. See Add a new Bundle if a new bundles should be created.
Important: See below if the output schema of the operator is different than the input schema.
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For the easy integration of new logical operators into to PQL query language, annotations should be used. Another way is to extend AbstractOperatorBuilder. In these annotations the name of the operator and number of minimal and maximal inputs and the parameters are described. In addition, the annotations may include some documentation and a URL for further information about the operator. These information are also available in the Odysseus Studio GUI.
On the right side, the whole implementation of the RouteAO can be found. Because predicates need to be initialized before the processing, they should be saved by the AbstractLogicalOperator.
Further information about the annotations can be found in the PQL documentation.
Changing the output schema
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For many operators the input schema and the output schema are the same but often you need to create you own output schema. For this, overwrite the method getInputSchemaInternal(port).
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