Scala builder from the Java POV

case class AppleHash(hash: UUID,
                     uuid: UUID)
object AppleHash {
  def builder = new Builder
  class Builder {
    private var hash: UUID = _
    private var uuid: UUID = _
    def hash(hash: UUID): Builder = {this.hash = hash; this }
    def uuid(uuid: UUID): Builder = {this.uuid = uuid; this }
    def build = AppleHash(hash = hash, uuid = uuid)
  }
}

// Java side

package com.vertigo.dp;

import java.util.UUID;

/** A {@code TestB} is an object that... */
public class TestB {
    public static void main(String[] args) {
        UUID hash = UUID.randomUUID();
        UUID uuid = UUID.randomUUID();
        AppleHash ah = AppleHash.builder()
            .hash(hash)
            .uuid(uuid)
            .build();
        System.out.println("ah = " + ah);
    }
}