Improve performance of Streams#stream

assertj · May 28, 2018 · 3aeaf37 · 3aeaf37
1 parent d9b6d37
commit 3aeaf37
Showing 1 changed file with 9 additions and 3 deletions.
diff --git a/src/main/java/org/assertj/core/util/Streams.java b/src/main/java/org/assertj/core/util/Streams.java
@@ -12,13 +12,19 @@
  */
 package org.assertj.core.util;
 
+import java.util.Collection;
 import java.util.stream.Stream;
 import java.util.stream.StreamSupport;
 
 public class Streams {
 
-  public static <T> Stream<T> stream(Iterable<T> actual) {
+  /**
-    return StreamSupport.stream(actual.spliterator(), false);
+   * Returns a sequential {@link Stream} of the contents of {@code iterable}, delegating to {@link
-
+   * Collection#stream} if possible.
+   */
+  public static <T> Stream<T> stream(Iterable<T> iterable) {
+    return (iterable instanceof Collection)
+        ? ((Collection<T>) iterable).stream()
+        : StreamSupport.stream(iterable.spliterator(), false);
   }
 }