com.johnsnowlabs.nlp.annotators.param.AnnotatorParam.scala Maven / Gradle / Ivy

/*
 * Copyright 2017-2022 John Snow Labs
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.johnsnowlabs.nlp.annotators.param

import org.apache.spark.ml.param.Param
import org.apache.spark.ml.util.Identifiable
import org.json4s._
import org.json4s.jackson.JsonMethods._
import org.json4s.jackson.Serialization.write

import java.util.{Date, TimeZone}

/** Structure to guideline a writable non-standard PARAM for any annotator Uses json4s jackson for
  * serialization
  *
  * @param identifiable
  *   Required for uid generation and storage as ML Params
  * @param name
  *   name of this Param, just like [[Param]]
  * @param description
  *   description of this Param, just like [[Param]]
  * @param m
  *   Implicit manifest constructor representation
  * @tparam A
  *   Any kind of Writable annotator component (usually a model approach)
  * @tparam B
  *   Any kind of serialized figure, of writable type
  */
class AnnotatorParam[A <: WritableAnnotatorComponent, B <: SerializedAnnotatorComponent[_ <: A]](
    identifiable: Identifiable,
    name: String,
    description: String)(implicit m: Manifest[B])
    extends Param[A](identifiable, name, description) {

  /** Workaround json4s issue of DefaultFormats not being Serializable in provided release */
  object SerializableFormat extends Formats with Serializable {
    class SerializableDateFormat extends DateFormat {
      def timezone: TimeZone =
        throw new Exception("SerializableFormat does not implement dateformat")

      override def format(d: Date): String =
        throw new Exception("SerializableFormat does not implement dateformat")

      override def parse(s: String): Option[Date] =
        throw new Exception("SerializableFormat does not implement dateformat")
    }

    override def dateFormat: DateFormat = new SerializableDateFormat
  }

  implicit val formats: SerializableFormat.type = SerializableFormat

  override def jsonEncode(value: A): String = write(value.serialize)

  override def jsonDecode(json: String): A = parse(json).extract[B].deserialize
}