Operator Objective

This operator receives an POJO (Plain Old Java Object) as an incoming tuple and based on the filter condition it emits filtered tuples on one output port and rest on another output port.

Filter operator supports quasi Java expressions to specify filter rule.

Filter operator does not hold any state and is idempotent, fault-tolerant and statically/dynamically partitionable.

Operator Usecase

  1. Customer data usually contains a field customer category/segment. One wants some analysis to be done for specific customer segment. One could use this filter operator to filter the records based on segment for some analysis for specific customer segment.
  2. Log data processing pipeline may want to filter logs from specific machine/router/switch.

Operator Information

  1. Operator location: malhar-library
  2. Available since: 3.5.0
  3. Operator state: Evolving
  4. Java Packages:

Properties, Attributes and Ports

Properties of FilterOperator

Property Description Type Mandatory Default Value
condition condition/expression with which Filtering is done. String Yes N/A
additionalExpressionFunctions List of import classes/method that should be made statically available to expression to use. List<String> No Empty List

Platform Attributes that influences operator behavior

Attribute Description Type Mandatory
port.input.attr.TUPLE_CLASS TUPLE_CLASS attribute on input port indicates the class of POJO which incoming tuple Class or FQCN Yes


Port Description Type Connection Required
input Tuple which needs to be filtered are received on this port Object (POJO) Yes
truePort Tuples which satisfies condition are emitted on this port Object (POJO) No
falsePort Tuples which does not satisfy condition are emitted on this port Object (POJO) No


Current FilterOperator has following limitation:

  1. APEXMALHAR-2175 : Filter condition is not able to correctly handle java reserved words.


Example for FilterOperator can be found at: