org.apache.flink.table.util.JavaScalaConversionUtil.scala Maven / Gradle / Ivy
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* to you 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,
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*/
package org.apache.flink.table.util
import java.util.Optional
import java.util.function.{BiConsumer, Consumer, Function}
import org.apache.flink.api.java.tuple.{Tuple2 => JTuple2}
/**
* Utilities for interoperability between Scala and Java classes.
*/
object JavaScalaConversionUtil {
// most of these methods are not necessary once we upgraded to Scala 2.12
def toJava[T](option: Option[T]): Optional[T] = option match {
case Some(v) => Optional.of(v)
case None => Optional.empty()
}
def toScala[T](option: Optional[T]): Option[T] = Option(option.orElse(null.asInstanceOf[T]))
def toJava[T](func: (T) => Unit): Consumer[T] = new Consumer[T] {
override def accept(t: T): Unit = {
func.apply(t)
}
}
def toJava[K, V](func: (K, V) => Unit): BiConsumer[K, V] = new BiConsumer[K, V] {
override def accept(k: K, v: V): Unit = {
func.apply(k ,v)
}
}
def toJava[I, O](func: (I) => O): Function[I, O] = new Function[I, O] {
override def apply(in: I): O = {
func.apply(in)
}
}
def toJava[T0, T1](tuple: (T0, T1)): JTuple2[T0, T1] = {
new JTuple2[T0, T1](tuple._1, tuple._2)
}
}