Clarify Location#getExtent javadocs
See
@@ -149,11 +149,12 @@ public Location(E extent, int x, int y, int z) {
/**
* Gets the underlying extent.
*
- * <p>Note: This can be null if the {@link Extent} is unloaded and garbage
- * collected.</p>
+ * <p>If the referenced {@link Extent} has been unloaded, this will throw
+ * an exception.</p>
*
* @return The extent, if available
- * @throws IllegalStateException If the {@link Extent} is null
+ * @throws IllegalStateException If the {@link Extent} has been unloaded and
+ * is no longer available.
*/
public E getExtent() {
final E currentExtent = this.extent.get();
