From dafcd16a142188af2c4c57caa1733f6fc19fce5a Mon Sep 17 00:00:00 2001
From: NotMyFault <mc.cache@web.de>
Date: Wed, 2 Mar 2022 20:48:49 +0100
Subject: [PATCH] Update Upstream

eac5b51 Play dirty because bukkit classloading is bad. (2043)
---
 .../bukkit/util/ClassSourceValidator.java     | 38 +++++++++++++++----
 1 file changed, 30 insertions(+), 8 deletions(-)

diff --git a/worldedit-bukkit/src/main/java/com/sk89q/bukkit/util/ClassSourceValidator.java b/worldedit-bukkit/src/main/java/com/sk89q/bukkit/util/ClassSourceValidator.java
index 1b1d59fc0..2ef7fbabb 100644
--- a/worldedit-bukkit/src/main/java/com/sk89q/bukkit/util/ClassSourceValidator.java
+++ b/worldedit-bukkit/src/main/java/com/sk89q/bukkit/util/ClassSourceValidator.java
@@ -25,8 +25,11 @@ import com.sk89q.worldedit.internal.util.LogManagerCompat;
 import org.apache.logging.log4j.Logger;
 import org.bukkit.Bukkit;
 import org.bukkit.plugin.Plugin;
+import org.bukkit.plugin.java.PluginClassLoader;
 
 import javax.annotation.Nullable;
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Locale;
@@ -40,8 +43,20 @@ import static com.google.common.base.Preconditions.checkNotNull;
  */
 public class ClassSourceValidator {
 
-    private static final Logger LOGGER = LogManagerCompat.getLogger();
     private static final String SEPARATOR_LINE = Strings.repeat("*", 46);
+    private static final Method loadClass;
+
+    static {
+        Method tmp;
+        try {
+            tmp = PluginClassLoader.class.getDeclaredMethod("loadClass0",
+                    String.class, boolean.class, boolean.class, boolean.class);
+            tmp.setAccessible(true);
+        } catch (NoSuchMethodException e) {
+            tmp = null;
+        }
+        loadClass = tmp;
+    }
 
     private final Plugin plugin;
     @Nullable
@@ -56,6 +71,9 @@ public class ClassSourceValidator {
         checkNotNull(plugin, "plugin");
         this.plugin = plugin;
         this.expectedClassLoader = plugin.getClass().getClassLoader();
+        if (loadClass == null) {
+            plugin.getLogger().info("Bukkit PluginClassLoader seems to have changed. Class source validation will be skipped.");
+        }
     }
 
     /**
@@ -67,7 +85,7 @@ public class ClassSourceValidator {
     public Map<Class<?>, Plugin> findMismatches(List<Class<?>> classes) {
         checkNotNull(classes, "classes");
 
-        if (expectedClassLoader == null) {
+        if (expectedClassLoader == null || loadClass == null) {
             return ImmutableMap.of();
         }
 
@@ -78,14 +96,18 @@ public class ClassSourceValidator {
                 continue;
             }
             ClassLoader targetLoader = target.getClass().getClassLoader();
+            if (!(targetLoader instanceof PluginClassLoader)) {
+                continue;
+            }
             for (Class<?> testClass : classes) {
-                ClassLoader testSource = null;
+                Class<?> targetClass;
                 try {
-                    testSource = targetLoader.loadClass(testClass.getName()).getClassLoader();
-                } catch (ClassNotFoundException ignored) {
+                    targetClass = (Class<?>) loadClass.invoke(targetLoader, testClass.getName(), false, false, false);
+                } catch (IllegalAccessException | InvocationTargetException ignored) {
+                    continue;
                 }
-                if (testSource != null && testSource != expectedClassLoader) {
-                    mismatches.putIfAbsent(testClass, testSource == targetLoader ? target : null);
+                if (targetClass.getClassLoader() != expectedClassLoader) {
+                    mismatches.putIfAbsent(testClass, targetClass.getClassLoader() == targetLoader ? target : null);
                 }
             }
         }
@@ -139,7 +161,7 @@ public class ClassSourceValidator {
         builder.append("** Please report this to the plugins' developers.\n");
         builder.append(SEPARATOR_LINE).append("\n");
 
-        LOGGER.error(builder.toString());
+        plugin.getLogger().severe(builder.toString());
     }
 
 }