diff --git a/MPChartLib/src/main/java/com/github/mikephil/charting/data/BarLineScatterCandleBubbleData.java b/MPChartLib/src/main/java/com/github/mikephil/charting/data/BarLineScatterCandleBubbleData.java
deleted file mode 100644
index c09eadec9b..0000000000
--- a/MPChartLib/src/main/java/com/github/mikephil/charting/data/BarLineScatterCandleBubbleData.java
+++ /dev/null
@@ -1,27 +0,0 @@
-
-package com.github.mikephil.charting.data;
-
-import com.github.mikephil.charting.interfaces.datasets.IBarLineScatterCandleBubbleDataSet;
-
-import java.util.List;
-
-/**
- * Baseclass for all Line, Bar, Scatter, Candle and Bubble data.
- * 
- * @author Philipp Jahoda
- */
-public abstract class BarLineScatterCandleBubbleData<T extends IBarLineScatterCandleBubbleDataSet<? extends Entry>>
-        extends ChartData<T> {
-    
-    public BarLineScatterCandleBubbleData() {
-        super();
-    }
-
-    public BarLineScatterCandleBubbleData(T... sets) {
-        super(sets);
-    }
-
-    public BarLineScatterCandleBubbleData(List<T> sets) {
-        super(sets);
-    }
-}
diff --git a/MPChartLib/src/main/java/com/github/mikephil/charting/data/BarLineScatterCandleBubbleData.kt b/MPChartLib/src/main/java/com/github/mikephil/charting/data/BarLineScatterCandleBubbleData.kt
new file mode 100644
index 0000000000..e3de277d75
--- /dev/null
+++ b/MPChartLib/src/main/java/com/github/mikephil/charting/data/BarLineScatterCandleBubbleData.kt
@@ -0,0 +1,14 @@
+package com.github.mikephil.charting.data
+
+import com.github.mikephil.charting.interfaces.datasets.IBarLineScatterCandleBubbleDataSet
+
+/**
+ * Baseclass for all Line, Bar, Scatter, Candle and Bubble data.
+ */
+abstract class BarLineScatterCandleBubbleData<T : IBarLineScatterCandleBubbleDataSet<out Entry>> : ChartData<T> {
+    constructor() : super()
+
+    constructor(vararg sets: T) : super(*sets)
+
+    constructor(sets: MutableList<T>) : super(sets)
+}
diff --git a/MPChartLib/src/main/java/com/github/mikephil/charting/data/LineData.kt b/MPChartLib/src/main/java/com/github/mikephil/charting/data/LineData.kt
index 232803aa6f..72dc16089b 100644
--- a/MPChartLib/src/main/java/com/github/mikephil/charting/data/LineData.kt
+++ b/MPChartLib/src/main/java/com/github/mikephil/charting/data/LineData.kt
@@ -5,10 +5,10 @@ import com.github.mikephil.charting.interfaces.datasets.ILineDataSet
 /**
  * Data object that encapsulates all data associated with a LineChart.
  */
-class LineData : BarLineScatterCandleBubbleData<ILineDataSet?> {
+class LineData : BarLineScatterCandleBubbleData<ILineDataSet> {
     constructor() : super()
 
     constructor(vararg dataSets: ILineDataSet) : super(*dataSets)
 
-    constructor(dataSets: MutableList<ILineDataSet>?) : super(dataSets)
+    constructor(dataSets: MutableList<ILineDataSet>) : super(dataSets)
 }
diff --git a/MPChartLib/src/main/java/com/github/mikephil/charting/listener/BarLineChartTouchListener.kt b/MPChartLib/src/main/java/com/github/mikephil/charting/listener/BarLineChartTouchListener.kt
index 92716c9916..3d530c8054 100644
--- a/MPChartLib/src/main/java/com/github/mikephil/charting/listener/BarLineChartTouchListener.kt
+++ b/MPChartLib/src/main/java/com/github/mikephil/charting/listener/BarLineChartTouchListener.kt
@@ -25,11 +25,11 @@ import kotlin.math.sqrt
  */
 @Suppress("MemberVisibilityCanBePrivate")
 class BarLineChartTouchListener(
-    chart: BarLineChartBase<out BarLineScatterCandleBubbleData<out IBarLineScatterCandleBubbleDataSet<out Entry>?>?>,
+    chart: BarLineChartBase<out BarLineScatterCandleBubbleData<out IBarLineScatterCandleBubbleDataSet<out Entry>>>,
     touchMatrix: Matrix,
     dragTriggerDistance: Float
 ) :
-    ChartTouchListener<BarLineChartBase<out BarLineScatterCandleBubbleData<out IBarLineScatterCandleBubbleDataSet<out Entry>?>?>?>(chart) {
+    ChartTouchListener<BarLineChartBase<out BarLineScatterCandleBubbleData<out IBarLineScatterCandleBubbleDataSet<out Entry>>?>?>(chart) {
     /**
      * the original touch-matrix from the chart
      */