Shutting down executor service to that application can exit cleanly

extras/rhubarb-for-spine/src/main/kotlin/com/rhubarb_lip_sync/rhubarb_for_spine/AnimationFileModel.kt

@@ -8,9 +8,9 @@ import java.nio.file.Path
 import tornadofx.getValue
 import tornadofx.observable
 import tornadofx.setValue
-import java.util.concurrent.Executors
+import java.util.concurrent.ExecutorService
 
-class AnimationFileModel(animationFilePath: Path) {
+class AnimationFileModel(animationFilePath: Path, private val executor: ExecutorService) {
 	val spineJson = SpineJson(animationFilePath)
 
 	val slotsProperty = SimpleObjectProperty<ObservableList<String>>()
@@ -50,7 +50,6 @@ class AnimationFileModel(animationFilePath: Path) {
 	var mouthShapesError by mouthShapesErrorProperty
 		private set
 
-	private val executor = Executors.newSingleThreadExecutor()
 	val audioFileModelsProperty = SimpleListProperty<AudioFileModel>(
 		spineJson.audioEvents
 			.map { event ->

extras/rhubarb-for-spine/src/main/kotlin/com/rhubarb_lip_sync/rhubarb_for_spine/MainModel.kt

@@ -8,8 +8,9 @@ import tornadofx.setValue
 import java.nio.file.Files
 import java.nio.file.InvalidPathException
 import java.nio.file.Paths
+import java.util.concurrent.ExecutorService
 
-class MainModel {
+class MainModel(private val executor: ExecutorService) {
 	val filePathStringProperty = SimpleStringProperty(getDefaultPathString()).alsoListen { value ->
 		filePathError = getExceptionMessage {
 			animationFileModel = null
@@ -28,7 +29,7 @@ class MainModel {
 				throw Exception("File does not exist.")
 			}
 
-			animationFileModel = AnimationFileModel(path)
+			animationFileModel = AnimationFileModel(path, executor)
 		}
 	}
 	var filePathString by filePathStringProperty

extras/rhubarb-for-spine/src/main/kotlin/com/rhubarb_lip_sync/rhubarb_for_spine/MainView.kt

@@ -14,10 +14,11 @@ import tornadofx.*
 import java.io.File
 import java.time.LocalDate
 import java.time.Period
+import java.util.concurrent.Executors
 
 class MainView : View() {
-
-	val mainModel = MainModel()
+	private val executor = Executors.newSingleThreadExecutor()
+	private val mainModel = MainModel(executor)
 
 	class Person(val id: Int, val name: String, val birthday: LocalDate) {
 		val age: Int get() = Period.between(birthday, LocalDate.now()).years
@@ -119,6 +120,10 @@ class MainView : View() {
 			}
 		}
 
+		whenUndocked {
+			executor.shutdownNow()
+		}
+
 		filePathButton!!.onAction = EventHandler<ActionEvent> {
 			val fileChooser = FileChooser().apply {
 				title = "Open Spine JSON file"