Throw exception on empty content list slots

Author: NichtStudioCode

invui/src/main/java/xyz/xenondevs/invui/gui/AbstractPagedGui.java

@@ -23,6 +23,9 @@ sealed abstract class AbstractPagedGui<C>
 
     public AbstractPagedGui(int width, int height, boolean infinitePages, int... contentListSlots) {
         super(width, height);
+        if (contentListSlots.length == 0)
+            throw new IllegalArgumentException("Content list slots must not be empty");
+        
         this.infinitePages = infinitePages;
         this.contentListSlots = contentListSlots;
     }

invui/src/main/java/xyz/xenondevs/invui/gui/AbstractScrollGui.java

@@ -27,6 +27,9 @@ sealed abstract class AbstractScrollGui<C>
 
     public AbstractScrollGui(int width, int height, boolean infiniteLines, int... contentListSlots) {
         super(width, height);
+        if (contentListSlots.length == 0)
+            throw new IllegalArgumentException("Content list slots must not be empty");
+        
         this.infiniteLines = infiniteLines;
         this.contentListSlots = contentListSlots;
         this.lineLength = SlotUtils.getLongestLineLength(contentListSlots, width);

invui/src/main/java/xyz/xenondevs/invui/gui/AbstractTabGui.java

@@ -21,6 +21,9 @@ sealed abstract class AbstractTabGui<C extends Gui>
 
     public AbstractTabGui(int width, int height, int tabAmount, int... listSlots) {
         super(width, height);
+        if (listSlots.length == 0)
+            throw new IllegalArgumentException("Content list slots must not be empty");
+        
         this.tabAmount = tabAmount;
         this.listSlots = listSlots;
     }