From 7da9984fc611a07e948d0d80d61471d12646488c Mon Sep 17 00:00:00 2001
From: Juuz <6596629+Juuxel@users.noreply.github.com>
Date: Fri, 10 Sep 2021 15:45:39 +0300
Subject: Document ObservableProperty.add/removeListener

---
 .../cottonmc/cotton/gui/widget/data/ObservableProperty.java  | 12 ++++++++++++
 1 file changed, 12 insertions(+)

(limited to 'src/main/java')

diff --git a/src/main/java/io/github/cottonmc/cotton/gui/widget/data/ObservableProperty.java b/src/main/java/io/github/cottonmc/cotton/gui/widget/data/ObservableProperty.java
index 3b0205e..7111b25 100644
--- a/src/main/java/io/github/cottonmc/cotton/gui/widget/data/ObservableProperty.java
+++ b/src/main/java/io/github/cottonmc/cotton/gui/widget/data/ObservableProperty.java
@@ -130,11 +130,23 @@ public final class ObservableProperty<T> implements Supplier<T> {
 		return this;
 	}
 
+	/**
+	 * Adds a change listener to this observable property.
+	 *
+	 * @param listener the added listener
+	 */
 	public void addListener(ChangeListener<? super T> listener) {
+		Objects.requireNonNull(listener);
 		listeners.add(listener);
 	}
 
+	/**
+	 * Removes a change listener from this observable property if present.
+	 *
+	 * @param listener the removed listener
+	 */
 	public void removeListener(ChangeListener<? super T> listener) {
+		Objects.requireNonNull(listener);
 		listeners.remove(listener);
 	}
 
-- 
cgit