Properly lookup plugin classes when looked up by spark

fixes #11124

patches/server/1043-Bundle-spark.patch

@@ -21,13 +21,15 @@ index 1a734293c9416f13324bb0edf8f950c9029f8bc4..568d0b65bb5010e0ab365cb47b624720
  paperweight {
 diff --git a/src/main/java/io/papermc/paper/SparksFly.java b/src/main/java/io/papermc/paper/SparksFly.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..785e85465c746dd66d1d3d648746cb1487d16d07
+index 0000000000000000000000000000000000000000..d589ae2aa89f386d96e4ff51dbc9f2aae1703598
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/SparksFly.java
-@@ -0,0 +1,179 @@
+@@ -0,0 +1,200 @@
 +package io.papermc.paper;
 +
 +import io.papermc.paper.configuration.GlobalConfiguration;
++import io.papermc.paper.plugin.ClassLoaderStorage;
++import io.papermc.paper.plugin.entrypoint.classloader.PaperSimplePluginClassLoader;
 +import io.papermc.paper.util.MCUtil;
 +import java.util.List;
 +import java.util.logging.Level;
@@ -42,6 +44,7 @@ index 0000000000000000000000000000000000000000..785e85465c746dd66d1d3d648746cb14
 +import org.bukkit.command.Command;
 +import org.bukkit.command.CommandSender;
 +import org.bukkit.craftbukkit.CraftServer;
++import org.bukkit.plugin.java.PluginClassLoader;
 +
 +// It's like electricity.
 +public final class SparksFly {
@@ -84,7 +87,25 @@ index 0000000000000000000000000000000000000000..785e85465c746dd66d1d3d648746cb14
 +        }, new PaperClassLookup() {
 +            @Override
 +            public Class<?> lookup(final String className) throws Exception {
++                try {
 +                    return Class.forName(className);
++                } catch (final Exception e) {
++                    for (final PaperSimplePluginClassLoader loader : ClassLoaderStorage.MODERN_LOADERS) {
++                        final Class<?> loadedClass = loader.loadClass(className);
++                        if (loadedClass != null) {
++                            return loadedClass;
++                        }
++                    }
++                    for (final PluginClassLoader loader : ClassLoaderStorage.LEGACY_LOADERS) {
++                        final Class<?> loadedClass = loader.loadClass(className, true, false, true);
++                        if (loadedClass != null) {
++                            return loadedClass;
++                        }
++                    }
++                    final ClassNotFoundException exception = new ClassNotFoundException("Could not find class " + className);
++                    exception.addSuppressed(e);
++                    throw exception;
++                }
 +            }
 +        });
 +    }
@@ -204,6 +225,43 @@ index 0000000000000000000000000000000000000000..785e85465c746dd66d1d3d648746cb14
 +        }
 +    }
 +}
+diff --git a/src/main/java/io/papermc/paper/plugin/ClassLoaderStorage.java b/src/main/java/io/papermc/paper/plugin/ClassLoaderStorage.java
+new file mode 100644
+index 0000000000000000000000000000000000000000..cb080d89b3be899de5007c799e6ef40809f2ef61
+--- /dev/null
++++ b/src/main/java/io/papermc/paper/plugin/ClassLoaderStorage.java
+@@ -0,0 +1,11 @@
++package io.papermc.paper.plugin;
++
++import io.papermc.paper.plugin.entrypoint.classloader.PaperSimplePluginClassLoader;
++import java.util.HashSet;
++import java.util.Set;
++import org.bukkit.plugin.java.PluginClassLoader;
++
++public final class ClassLoaderStorage {
++    public static final Set<PaperSimplePluginClassLoader> MODERN_LOADERS = new HashSet<>();
++    public static final Set<PluginClassLoader> LEGACY_LOADERS = new HashSet<>();
++}
+diff --git a/src/main/java/io/papermc/paper/plugin/entrypoint/classloader/PaperSimplePluginClassLoader.java b/src/main/java/io/papermc/paper/plugin/entrypoint/classloader/PaperSimplePluginClassLoader.java
+index 967465e542483e93a736129b5f5c6622cefd33fa..f8094525064b46fe78f5b5f32ea53b234b4d525d 100644
+--- a/src/main/java/io/papermc/paper/plugin/entrypoint/classloader/PaperSimplePluginClassLoader.java
++++ b/src/main/java/io/papermc/paper/plugin/entrypoint/classloader/PaperSimplePluginClassLoader.java
+@@ -1,5 +1,6 @@
+ package io.papermc.paper.plugin.entrypoint.classloader;
+ 
++import io.papermc.paper.plugin.ClassLoaderStorage;
+ import io.papermc.paper.plugin.configuration.PluginMeta;
+ import io.papermc.paper.plugin.util.NamespaceChecker;
+ import org.jetbrains.annotations.ApiStatus;
+@@ -40,6 +41,8 @@ public class PaperSimplePluginClassLoader extends URLClassLoader {
+         this.jarUrl = source.toUri().toURL();
+         this.configuration = configuration;
+         this.jar = file;
++
++        ClassLoaderStorage.MODERN_LOADERS.add(this); // Paper - spark
+     }
+ 
+     @Override
 diff --git a/src/main/java/io/papermc/paper/plugin/provider/source/FileProviderSource.java b/src/main/java/io/papermc/paper/plugin/provider/source/FileProviderSource.java
 index 6b8ed8a0baaf4a57d20e57cec3400af5561ddd79..48604e7f96adc9e226e034054c5e2bad0b024eb5 100644
 --- a/src/main/java/io/papermc/paper/plugin/provider/source/FileProviderSource.java
@@ -246,6 +304,26 @@ index 6b8ed8a0baaf4a57d20e57cec3400af5561ddd79..48604e7f96adc9e226e034054c5e2bad
          type.register(entrypointHandler, file, context);
      }
  
+diff --git a/src/main/java/io/papermc/paper/plugin/provider/type/spigot/SpigotPluginProvider.java b/src/main/java/io/papermc/paper/plugin/provider/type/spigot/SpigotPluginProvider.java
+index 0fd1040ed376f19c6d5326767baaf3048ce1bfb4..a9fd3f34aca19b1cfada5b771b3d46a2cfca4c51 100644
+--- a/src/main/java/io/papermc/paper/plugin/provider/type/spigot/SpigotPluginProvider.java
++++ b/src/main/java/io/papermc/paper/plugin/provider/type/spigot/SpigotPluginProvider.java
+@@ -2,6 +2,7 @@ package io.papermc.paper.plugin.provider.type.spigot;
+ 
+ import com.destroystokyo.paper.util.SneakyThrow;
+ import com.destroystokyo.paper.utils.PaperPluginLogger;
++import io.papermc.paper.plugin.ClassLoaderStorage;
+ import io.papermc.paper.plugin.manager.PaperPluginManagerImpl;
+ import io.papermc.paper.plugin.provider.configuration.LoadOrderConfiguration;
+ import io.papermc.paper.plugin.provider.entrypoint.DependencyContext;
+@@ -133,6 +134,7 @@ public class SpigotPluginProvider implements PluginProvider<JavaPlugin>, Provide
+             // We must provide a temporary context in order to properly handle dependencies on the plugin classloader constructor.
+             loader.dependencyContext = PaperPluginManagerImpl.getInstance();
+ 
++            ClassLoaderStorage.LEGACY_LOADERS.add(loader); // Paper - spark
+ 
+             this.status = ProviderStatus.INITIALIZED;
+             return loader.getPlugin();
 diff --git a/src/main/java/net/minecraft/server/MinecraftServer.java b/src/main/java/net/minecraft/server/MinecraftServer.java
 index 8160c35368fc2c52d6f4a42df27adb2ef6eb87f3..9325d6f95165a7cee00d7de736af723681cc16b4 100644
 --- a/src/main/java/net/minecraft/server/MinecraftServer.java