apply some refactoring recommendations

common/src/main/java/de/nicidienase/chaosflix/common/mediadata/entities/recording/ConferenceDto.kt

@@ -25,13 +25,13 @@ data class ConferenceDto(
     val conferenceID: Long
         get() = getIdFromUrl()
 
-    val eventsByTags: Map<String, List<EventDto>> by lazy { getEventsMap(events) }
-    val sensibleTags: Set<String>
+    private val eventsByTags: Map<String, List<EventDto>> by lazy { getEventsMap(events) }
+    private val sensibleTags: Set<String>
     val tagsUsefull: Boolean
 
     init {
         sensibleTags = ConferenceUtil.getSensibleTags(eventsByTags.keys, acronym)
-        tagsUsefull = sensibleTags.size > 0
+        tagsUsefull = sensibleTags.isNotEmpty()
     }
 
     private fun getEventsMap(events: List<EventDto>?): Map<String, List<EventDto>> {
@@ -39,15 +39,15 @@ data class ConferenceDto(
         val untagged = ArrayList<EventDto>()
         if (events != null) {
             for (event in events) {
-                if (event.tags?.isNotEmpty() ?: false) {
+                if (event.tags?.isNotEmpty() == true) {
                     for (tag in event.tags!!) {
 
                         val list: MutableList<EventDto>
                         if (map.keys.contains(tag)) {
                             list = map[tag]!!
                         } else {
-                            list = ArrayList<EventDto>()
-                            map.put(tag, list)
+                            list = ArrayList()
+                            map[tag] = list
                         }
                         list.add(event)
                     }
@@ -56,7 +56,7 @@ data class ConferenceDto(
                 }
             }
             if (untagged.size > 0) {
-                map.put("untagged", untagged)
+                map["untagged"] = untagged
             }
         }
         return map

common/src/main/java/de/nicidienase/chaosflix/common/mediadata/entities/recording/persistence/Event.kt

@@ -12,11 +12,11 @@ import android.text.Spanned
 import de.nicidienase.chaosflix.common.mediadata.entities.recording.EventDto
 
 @Entity(tableName = "event",
-        foreignKeys = arrayOf(ForeignKey(
-                entity = Conference::class,
-                onDelete = ForeignKey.CASCADE,
-                parentColumns = (arrayOf("id")),
-                childColumns = arrayOf("conferenceId"))),
+        foreignKeys = [ForeignKey(
+            entity = Conference::class,
+            onDelete = ForeignKey.CASCADE,
+            parentColumns = (arrayOf("id")),
+            childColumns = arrayOf("conferenceId"))],
         indices = [
             Index("guid", unique = true),
             Index("frontendLink"),
@@ -82,8 +82,7 @@ data class Event(
             parcel.createStringArray(),
             parcel.createStringArray(),
             parcel.createTypedArrayList(RelatedEvent),
-            parcel.createTypedArrayList(Recording)) {
-    }
+            parcel.createTypedArrayList(Recording))
 
     @Ignore
     constructor(event: EventDto, conferenceId: Long = 0) : this(

common/src/main/java/de/nicidienase/chaosflix/common/mediadata/entities/recording/persistence/Recording.kt

@@ -10,15 +10,17 @@ import android.os.Parcelable
 import de.nicidienase.chaosflix.common.mediadata.entities.recording.RecordingDto
 
 @Entity(tableName = "recording",
-        foreignKeys = arrayOf(ForeignKey(
-                entity = Event::class,
-                onDelete = ForeignKey.CASCADE,
-                parentColumns = (arrayOf("id")),
-                childColumns = arrayOf("eventId"))),
-        indices = arrayOf(
-                Index("eventId"),
-                Index("url", unique = true),
-                Index("backendId", unique = true)))
+        foreignKeys = [ForeignKey(
+            entity = Event::class,
+            onDelete = ForeignKey.CASCADE,
+            parentColumns = ([("id")]),
+            childColumns = ["eventId"])],
+        indices = [
+            Index("eventId"),
+            Index("url", unique = true),
+            Index("backendId", unique = true)
+        ]
+)
 data class Recording(
     @PrimaryKey(autoGenerate = true)
     var id: Long = 0,
@@ -60,8 +62,7 @@ data class Recording(
             parcel.readString() ?: "",
             parcel.readString() ?: "",
             parcel.readString() ?: "",
-            parcel.readLong()) {
-    }
+            parcel.readLong())
 
     @Ignore
     constructor(rec: RecordingDto, eventId: Long = 0) : this(

common/src/main/java/de/nicidienase/chaosflix/common/mediadata/sync/Downloader.kt

@@ -188,9 +188,7 @@ class Downloader(
         val conferenceId = database.conferenceDao().findConferenceByAcronymSync(acronym)?.id
                 ?: updateConferencesAndGet(acronym)
 
-        if (conferenceId == -1L) {
-            throw IllegalStateException("Could not find Conference for event")
-        }
+        check(conferenceId != -1L) { "Could not find Conference for event" }
 
         val persistentEvent = Event(event, conferenceId)
         val id = database.eventDao().insert(persistentEvent)