From 391b71a3d09370bde890dc80404f4aed04777804 Mon Sep 17 00:00:00 2001
From: "He-Pin(kerr)" <hepin1989@gmail.com>
Date: Mon, 22 Sep 2025 17:16:17 +0800
Subject: [PATCH] chore: Rewrite ClassContext with scala (#2260)

---
 .../actor/typed/internal/LoggerClass.scala    | 13 +++++-
 .../org/apache/pekko/util/ClassContext.java   | 41 -------------------
 2 files changed, 11 insertions(+), 43 deletions(-)
 delete mode 100644 actor/src/main/java/org/apache/pekko/util/ClassContext.java

diff --git a/actor-typed/src/main/scala/org/apache/pekko/actor/typed/internal/LoggerClass.scala b/actor-typed/src/main/scala/org/apache/pekko/actor/typed/internal/LoggerClass.scala
index 555c738550..a47ba35479 100644
--- a/actor-typed/src/main/scala/org/apache/pekko/actor/typed/internal/LoggerClass.scala
+++ b/actor-typed/src/main/scala/org/apache/pekko/actor/typed/internal/LoggerClass.scala
@@ -17,7 +17,7 @@ import scala.util.control.NonFatal
 
 import org.apache.pekko
 import pekko.annotation.InternalApi
-import pekko.util.{ ClassContext, OptionVal }
+import pekko.util.OptionVal
 
 /**
  * INTERNAL API
@@ -26,6 +26,15 @@ import pekko.util.{ ClassContext, OptionVal }
 private[pekko] object LoggerClass {
 
   private val defaultPrefixesToSkip = List("scala.runtime", "org.apache.pekko.actor.typed.internal")
+  private val OPTIONS: java.util.Set[StackWalker.Option] = java.util.Set.of(
+    StackWalker.Option.RETAIN_CLASS_REFERENCE, StackWalker.Option.SHOW_HIDDEN_FRAMES)
+  private val CLASS_STACK_WALKER: java.util.function.Function[
+    java.util.stream.Stream[StackWalker.StackFrame], Array[Class[_]]] =
+    (frames: java.util.stream.Stream[StackWalker.StackFrame]) =>
+      frames.map(frame => frame.getDeclaringClass)
+        .toArray[Class[_]]((size: Int) => new Array[Class[_]](size))
+
+  private def getClassStack: Array[Class[_]] = StackWalker.getInstance(OPTIONS).walk(CLASS_STACK_WALKER)
 
   /**
    * Try to extract a logger class from the call stack, if not possible the provided default is used
@@ -43,7 +52,7 @@ private[pekko] object LoggerClass {
         loop(additionalPrefixesToSkip ::: defaultPrefixesToSkip)
       }
 
-      val trace = ClassContext.getClassStack
+      val trace = getClassStack
       var suitableClass: OptionVal[Class[_]] = OptionVal.None
       var idx = 1 // skip this method/class and right away
       while (suitableClass.isEmpty && idx < trace.length) {
diff --git a/actor/src/main/java/org/apache/pekko/util/ClassContext.java b/actor/src/main/java/org/apache/pekko/util/ClassContext.java
deleted file mode 100644
index d47d638ae5..0000000000
--- a/actor/src/main/java/org/apache/pekko/util/ClassContext.java
+++ /dev/null
@@ -1,41 +0,0 @@
-/*
- * Licensed to the Apache Software Foundation (ASF) under one or more
- * contributor license agreements. See the NOTICE file distributed with
- * this work for additional information regarding copyright ownership.
- * The ASF licenses this file to You under the Apache License, Version 2.0
- * (the "License"); you may not use this file except in compliance with
- * the License. You may obtain a copy of the License at
- *
- *    http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package org.apache.pekko.util;
-
-import java.util.Set;
-import java.util.function.Function;
-import java.util.stream.Stream;
-import org.apache.pekko.annotation.InternalApi;
-
-/** INTERNAL API */
-@InternalApi
-public final class ClassContext {
-  private ClassContext() {
-    throw new UnsupportedOperationException("Cannot instantiate utility class");
-  }
-
-  private static final Set<StackWalker.Option> OPTIONS =
-      Set.of(StackWalker.Option.RETAIN_CLASS_REFERENCE, StackWalker.Option.SHOW_HIDDEN_FRAMES);
-
-  private static final Function<Stream<StackWalker.StackFrame>, Class<?>[]> CLASS_STACK_WALKER =
-      frames -> frames.map(StackWalker.StackFrame::getDeclaringClass).toArray(Class<?>[]::new);
-
-  public static Class<?>[] getClassStack() {
-    return StackWalker.getInstance(OPTIONS).walk(CLASS_STACK_WALKER);
-  }
-}