From a5c5f7ee950f4bcda447651e63ff58418d031843 Mon Sep 17 00:00:00 2001
From: cpovirk <cpovirk@google.com>
Date: Tue, 20 Jun 2023 08:19:26 -0700
Subject: [PATCH] Partial rollback of cl/441881361 to fix
 https://github.com/google/guava/issues/6565

Fixes https://github.com/google/guava/pull/6565

RELNOTES=`cache`: Fixed `BootstrapMethodError` when [using `CacheBuilder` from a custom system class loader](https://github.com/google/guava/issues/6565).
PiperOrigin-RevId: 541928922
---
 .../com/google/common/cache/CacheBuilder.java | 23 +++++++++++++------
 .../com/google/common/cache/CacheBuilder.java | 23 +++++++++++++------
 2 files changed, 32 insertions(+), 14 deletions(-)

diff --git a/android/guava/src/com/google/common/cache/CacheBuilder.java b/android/guava/src/com/google/common/cache/CacheBuilder.java
index f52243e4d4ff..69b095d7e307 100644
--- a/android/guava/src/com/google/common/cache/CacheBuilder.java
+++ b/android/guava/src/com/google/common/cache/CacheBuilder.java
@@ -228,15 +228,24 @@ public CacheStats snapshot() {
   static final CacheStats EMPTY_STATS = new CacheStats(0, 0, 0, 0, 0, 0);
 
   /*
-   * We avoid using a method reference here for now: Inside Google, CacheBuilder is used from the
-   * implementation of a custom ClassLoader that is sometimes used as a system classloader. That's a
-   * problem because method-reference linking tries to look up the system classloader, and it fails
-   * because there isn't one yet.
+   * We avoid using a method reference or lambda here for now:
    *
-   * I would have guessed that a lambda would produce the same problem, but maybe it's safe because
-   * the lambda implementation is generated as a method in the _same class_ as the usage?
+   * - method reference: Inside Google, CacheBuilder is used from the implementation of a custom
+   *   ClassLoader that is sometimes used as a system classloader. That's a problem because
+   *   method-reference linking tries to look up the system classloader, and it fails because there
+   *   isn't one yet.
+   *
+   * - lambda: Outside Google, we got a report of a similar problem in
+   *   https://github.com/google/guava/issues/6565
    */
-  static final Supplier<StatsCounter> CACHE_STATS_COUNTER = () -> new SimpleStatsCounter();
+  @SuppressWarnings("AnonymousToLambda")
+  static final Supplier<StatsCounter> CACHE_STATS_COUNTER =
+      new Supplier<StatsCounter>() {
+        @Override
+        public StatsCounter get() {
+          return new SimpleStatsCounter();
+        }
+      };
 
   enum NullListener implements RemovalListener<Object, Object> {
     INSTANCE;
diff --git a/guava/src/com/google/common/cache/CacheBuilder.java b/guava/src/com/google/common/cache/CacheBuilder.java
index 35e9196e12ac..6e6458651397 100644
--- a/guava/src/com/google/common/cache/CacheBuilder.java
+++ b/guava/src/com/google/common/cache/CacheBuilder.java
@@ -229,15 +229,24 @@ public CacheStats snapshot() {
   static final CacheStats EMPTY_STATS = new CacheStats(0, 0, 0, 0, 0, 0);
 
   /*
-   * We avoid using a method reference here for now: Inside Google, CacheBuilder is used from the
-   * implementation of a custom ClassLoader that is sometimes used as a system classloader. That's a
-   * problem because method-reference linking tries to look up the system classloader, and it fails
-   * because there isn't one yet.
+   * We avoid using a method reference or lambda here for now:
    *
-   * I would have guessed that a lambda would produce the same problem, but maybe it's safe because
-   * the lambda implementation is generated as a method in the _same class_ as the usage?
+   * - method reference: Inside Google, CacheBuilder is used from the implementation of a custom
+   *   ClassLoader that is sometimes used as a system classloader. That's a problem because
+   *   method-reference linking tries to look up the system classloader, and it fails because there
+   *   isn't one yet.
+   *
+   * - lambda: Outside Google, we got a report of a similar problem in
+   *   https://github.com/google/guava/issues/6565
    */
-  static final Supplier<StatsCounter> CACHE_STATS_COUNTER = () -> new SimpleStatsCounter();
+  @SuppressWarnings("AnonymousToLambda")
+  static final Supplier<StatsCounter> CACHE_STATS_COUNTER =
+      new Supplier<StatsCounter>() {
+        @Override
+        public StatsCounter get() {
+          return new SimpleStatsCounter();
+        }
+      };
 
   enum NullListener implements RemovalListener<Object, Object> {
     INSTANCE;