add annotations to QuadTree

core/src/main/java/com/seibel/distanthorizons/core/util/objects/quadTree/QuadTree.java

@@ -31,6 +31,7 @@ import com.seibel.distanthorizons.core.util.gridList.MovableGridRingList;
 import it.unimi.dsi.fastutil.longs.LongArrayFIFOQueue;
 import it.unimi.dsi.fastutil.longs.LongIterator;
 import org.apache.logging.log4j.Logger;
+import org.jetbrains.annotations.Nullable;
 
 import java.util.*;
 import java.util.function.Consumer;
@@ -96,8 +97,10 @@ public class QuadTree<T>
 	//=====================//
 	
 	/** @return the node at the given section position */
+	@Nullable
 	public final QuadNode<T> getNode(long pos) throws IndexOutOfBoundsException { return this.getOrSetNode(pos, false, null, true); }
 	/** @return the value at the given section position */
+	@Nullable
 	public final T getValue(long pos) throws IndexOutOfBoundsException
 	{
 		QuadNode<T> node = this.getNode(pos);
@@ -109,6 +112,7 @@ public class QuadTree<T>
 	}
 	
 	/** @return the value that was previously in the given position, null if nothing */
+	@Nullable
 	public final T setValue(long pos, T value) throws IndexOutOfBoundsException
 	{
 		T previousValue = this.getValue(pos);
@@ -117,6 +121,7 @@ public class QuadTree<T>
 	}
 	
 	/** @param runBoundaryChecks should only ever be set to true internally for removing out of bound nodes */
+	@Nullable
 	protected final QuadNode<T> getOrSetNode(long pos, boolean setNewValue, T newValue, boolean runBoundaryChecks) throws IndexOutOfBoundsException
 	{
 		if (runBoundaryChecks && !this.isSectionPosInBounds(pos))