ScalaUDFExample

ExampleScalaUDF.scala

package in.ixixi.norikra.udf

import com.espertech.esper.epl.agg.aggregator.AggregationMethod

class ExampleScalaUDF extends AggregationMethod{

  var counter = 0L

  def getValueType: Class[_] = classOf[Long]

  def enter(value: AnyRef) { counter += value.toString.length }

  def leave(value: AnyRef) { counter -= value.toString.length }

  def getValue: AnyRef = (counter:java.lang.Long):AnyRef

  def clear { counter = 0L }
}

ExampleScalaUDFFactory.scala

package in.ixixi.norikra.udf

import com.espertech.esper.client.hook.AggregationFunctionFactory
import com.espertech.esper.epl.agg.aggregator.AggregationMethod
import com.espertech.esper.epl.agg.service.AggregationValidationContext

class ExampleScalaUDFFactory extends AggregationFunctionFactory{

  def setFunctionName(functionName: String)

  def validate(validationContext: AggregationValidationContext)

  def getValueType: Class[_] = classOf[Long]

  def newAggregator: AggregationMethod = new ExampleScalaUDF
}

udf_scala_example.rb

require 'java'
require 'norikra/udf'

module Norikra
  module UDF
    class ScalaUDFExample < Norikra::UDF::AggregationSingle
      def self.init
        require 'norikra-udf-scala-example.jar'
      end
      def definition
        ["strlength", "in.ixixi.norikra.udf.ExampleScalaUDFFactory"]
      end
    end
  end
end