From 8bbc5b5265ef5e80becb6d34c0a33e79ff95e11f Mon Sep 17 00:00:00 2001
From: Glavo <zjx001202@gmail.com>
Date: Fri, 9 Aug 2024 21:15:16 +0800
Subject: [PATCH] Simplify ImmutableArray

---
 .../collection/immutable/ImmutableArray.java  | 20 +++++++------------
 1 file changed, 7 insertions(+), 13 deletions(-)

diff --git a/kala-collection/src/main/java/kala/collection/immutable/ImmutableArray.java b/kala-collection/src/main/java/kala/collection/immutable/ImmutableArray.java
index 1dc930a9..72c3dae4 100644
--- a/kala-collection/src/main/java/kala/collection/immutable/ImmutableArray.java
+++ b/kala-collection/src/main/java/kala/collection/immutable/ImmutableArray.java
@@ -124,26 +124,20 @@ public static <E> ImmutableArray<E> narrow(ImmutableArray<? extends E> array) {
     }
 
     public static <E> @NotNull ImmutableArray<E> from(@NotNull java.util.Collection<? extends E> values) {
-        if (values.size() == 0) {
+        if (values.isEmpty()) { // implicit null check of values
             return empty();
         }
         return new ImmutableArray<>(values.toArray());
     }
 
     public static <E> @NotNull ImmutableArray<E> from(@NotNull Iterable<? extends E> values) {
-        Objects.requireNonNull(values);
+        return switch (values) { // implicit null check of values
+            case ImmutableArray<?> immutableArray -> ((ImmutableArray<E>) values);
+            case Traversable<?> traversable -> from((Traversable<E>) values);
+            case java.util.Collection<?> collection -> from(((java.util.Collection<E>) values));
+            default -> MutableArrayList.<E>from(values).toImmutableArray();
+        };
 
-        if (values instanceof ImmutableArray) {
-            return ((ImmutableArray<E>) values);
-        }
-        if (values instanceof Traversable) {
-            return from((Traversable<E>) values);
-        }
-        if (values instanceof java.util.Collection) {
-            return from(((java.util.Collection<E>) values));
-        }
-
-        return MutableArrayList.<E>from(values).toImmutableArray();
     }
 
     public static <E> @NotNull ImmutableArray<E> from(@NotNull Iterator<? extends E> it) {