From ebe887fc6890a5203ff4fc897ad3667d94ba641f Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Mon, 23 Feb 2026 20:07:15 +0000
Subject: [PATCH 1/3] Initial plan


From 89ed6e0c6ca3beb8c540fb2993cfe607c93aa711 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Mon, 23 Feb 2026 20:10:24 +0000
Subject: [PATCH 2/3] Suggest Stream.toList() in Unmodifiable collectors
 pattern

Co-authored-by: brunoborges <129743+brunoborges@users.noreply.github.com>
---
 content/collections/unmodifiable-collectors.json | 4 ++--
 content/streams/stream-tolist.json               | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/content/collections/unmodifiable-collectors.json b/content/collections/unmodifiable-collectors.json
index 0a9b1f5..08fcd24 100644
--- a/content/collections/unmodifiable-collectors.json
+++ b/content/collections/unmodifiable-collectors.json
@@ -12,7 +12,7 @@
   "oldCode": "List<String> list = stream.collect(\n    Collectors.collectingAndThen(\n        Collectors.toList(),\n        Collections::unmodifiableList\n    )\n);",
   "modernCode": "List<String> list = stream.collect(\n    Collectors.toUnmodifiableList()\n);",
   "summary": "Collect directly to unmodifiable collections.",
-  "explanation": "Java 10 added toUnmodifiableList(), toUnmodifiableSet(), and toUnmodifiableMap() collectors. No more wrapping with collectingAndThen.",
+  "explanation": "Java 10 added toUnmodifiableList(), toUnmodifiableSet(), and toUnmodifiableMap() collectors. No more wrapping with collectingAndThen. For lists specifically, Java 16+ stream.toList() is even simpler — it returns an unmodifiable List without the collect() call.",
   "whyModernWins": [
     {
       "icon": "📏",
@@ -39,7 +39,7 @@
   "related": [
     "collections/immutable-map-creation",
     "collections/immutable-set-creation",
-    "collections/map-entry-factory"
+    "streams/stream-tolist"
   ],
   "docs": [
     {
diff --git a/content/streams/stream-tolist.json b/content/streams/stream-tolist.json
index 43b510c..4c6dbcc 100644
--- a/content/streams/stream-tolist.json
+++ b/content/streams/stream-tolist.json
@@ -37,7 +37,7 @@
   "prev": "streams/collectors-flatmapping",
   "next": "streams/stream-mapmulti",
   "related": [
-    "streams/virtual-thread-executor",
+    "collections/unmodifiable-collectors",
     "streams/stream-gatherers",
     "streams/stream-iterate-predicate"
   ],

From 73bec43c39f9dba05a8664fc22f37b21a1b3eb4c Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Tue, 24 Feb 2026 16:20:42 +0000
Subject: [PATCH 3/3] Highlight stream.toList() as the modern approach in
 Unmodifiable collectors

Co-authored-by: brunoborges <129743+brunoborges@users.noreply.github.com>
---
 .../collections/unmodifiable-collectors.json  | 28 +++++++++++--------
 1 file changed, 16 insertions(+), 12 deletions(-)

diff --git a/content/collections/unmodifiable-collectors.json b/content/collections/unmodifiable-collectors.json
index 08fcd24..57f8705 100644
--- a/content/collections/unmodifiable-collectors.json
+++ b/content/collections/unmodifiable-collectors.json
@@ -4,20 +4,20 @@
   "title": "Unmodifiable collectors",
   "category": "collections",
   "difficulty": "intermediate",
-  "jdkVersion": "10",
+  "jdkVersion": "16",
   "oldLabel": "Java 8",
-  "modernLabel": "Java 10+",
+  "modernLabel": "Java 16+",
   "oldApproach": "collectingAndThen",
-  "modernApproach": "toUnmodifiable*()",
+  "modernApproach": "stream.toList()",
   "oldCode": "List<String> list = stream.collect(\n    Collectors.collectingAndThen(\n        Collectors.toList(),\n        Collections::unmodifiableList\n    )\n);",
-  "modernCode": "List<String> list = stream.collect(\n    Collectors.toUnmodifiableList()\n);",
-  "summary": "Collect directly to unmodifiable collections.",
-  "explanation": "Java 10 added toUnmodifiableList(), toUnmodifiableSet(), and toUnmodifiableMap() collectors. No more wrapping with collectingAndThen. For lists specifically, Java 16+ stream.toList() is even simpler — it returns an unmodifiable List without the collect() call.",
+  "modernCode": "List<String> list = stream.toList();",
+  "summary": "Collect directly to an unmodifiable list with stream.toList().",
+  "explanation": "Java 10 added toUnmodifiableList(), toUnmodifiableSet(), and toUnmodifiableMap() to replace the verbose collectingAndThen wrapper. For lists specifically, Java 16's stream.toList() provides an even simpler alternative — no collect() call at all. Use toUnmodifiableSet() and toUnmodifiableMap() for other collection types.",
   "whyModernWins": [
     {
       "icon": "📏",
-      "title": "Direct",
-      "desc": "One collector instead of wrapping with collectingAndThen."
+      "title": "Shortest yet",
+      "desc": "stream.toList() needs no collect() or Collectors import at all."
     },
     {
       "icon": "🔒",
@@ -25,14 +25,14 @@
       "desc": "Result cannot be modified — no accidental mutations."
     },
     {
-      "icon": "🚫",
-      "title": "Null-safe",
-      "desc": "Rejects null elements during collection."
+      "icon": "📖",
+      "title": "Readable",
+      "desc": "Reads naturally as the terminal step of any stream pipeline."
     }
   ],
   "support": {
     "state": "available",
-    "description": "Widely available since JDK 10 (March 2018)"
+    "description": "Widely available since JDK 16 (March 2021)"
   },
   "prev": "collections/reverse-list-iteration",
   "next": "strings/string-isblank",
@@ -42,6 +42,10 @@
     "streams/stream-tolist"
   ],
   "docs": [
+    {
+      "title": "Stream.toList()",
+      "href": "https://docs.oracle.com/en/java/javase/25/docs/api/java.base/java/util/stream/Stream.html#toList()"
+    },
     {
       "title": "Collectors.toUnmodifiableList()",
       "href": "https://docs.oracle.com/en/java/javase/25/docs/api/java.base/java/util/stream/Collectors.html#toUnmodifiableList()"