improve BanList types

paper-api/src/main/java/io/papermc/paper/ban/BanListType.java

@@ -0,0 +1,30 @@
+package io.papermc.paper.ban;
+
+import org.bukkit.BanList;
+import org.bukkit.ban.IpBanList;
+import org.bukkit.ban.ProfileBanList;
+import org.jspecify.annotations.NullMarked;
+
+/**
+ * Represents a ban-type that a {@link BanList} may track.
+ * It enforces the correct return value at compile time.
+ */
+@NullMarked
+public interface BanListType<T> {
+
+    /**
+     * Banned IP addresses
+     */
+    BanListType<IpBanList> IP = new BanListTypeImpl<>(IpBanList.class);
+    /**
+     * Banned player profiles
+     */
+    BanListType<ProfileBanList> PROFILE = new BanListTypeImpl<>(ProfileBanList.class);
+
+    /**
+     * Returns the type class of the ban list used generically
+     *
+     * @return the type class
+     */
+    Class<T> typeClass();
+}

paper-api/src/main/java/io/papermc/paper/ban/BanListTypeImpl.java

@@ -0,0 +1,9 @@
+package io.papermc.paper.ban;
+
+import org.jetbrains.annotations.ApiStatus;
+import org.jspecify.annotations.NullMarked;
+
+@ApiStatus.Internal
+@NullMarked
+record BanListTypeImpl<T>(Class<T> typeClass) implements BanListType<T> {
+}