Paper Plugins

Co-authored-by: Micah Rao <micah.s.rao@gmail.com>

paper-server/src/main/java/io/papermc/paper/plugin/manager/DummyBukkitPluginLoader.java

@@ -0,0 +1,82 @@
+package io.papermc.paper.plugin.manager;
+
+import io.papermc.paper.plugin.configuration.PluginMeta;
+import io.papermc.paper.plugin.provider.type.PluginFileType;
+import org.bukkit.Bukkit;
+import org.bukkit.event.Event;
+import org.bukkit.event.Listener;
+import org.bukkit.plugin.InvalidDescriptionException;
+import org.bukkit.plugin.InvalidPluginException;
+import org.bukkit.plugin.Plugin;
+import org.bukkit.plugin.PluginDescriptionFile;
+import org.bukkit.plugin.PluginLoader;
+import org.bukkit.plugin.RegisteredListener;
+import org.bukkit.plugin.UnknownDependencyException;
+import org.jetbrains.annotations.ApiStatus;
+import org.jetbrains.annotations.NotNull;
+
+import java.io.File;
+import java.io.FileNotFoundException;
+import java.io.IOException;
+import java.util.Map;
+import java.util.Set;
+import java.util.jar.JarFile;
+import java.util.regex.Pattern;
+
+/**
+ * A purely internal type that implements the now deprecated {@link PluginLoader} after the implementation
+ * of papers new plugin system.
+ */
+@ApiStatus.Internal
+public class DummyBukkitPluginLoader implements PluginLoader {
+
+    private static final Pattern[] PATTERNS = new Pattern[0];
+
+    @Override
+    public @NotNull Plugin loadPlugin(@NotNull File file) throws InvalidPluginException, UnknownDependencyException {
+        try {
+            return PaperPluginManagerImpl.getInstance().loadPlugin(file);
+        } catch (InvalidDescriptionException e) {
+            throw new InvalidPluginException(e);
+        }
+    }
+
+    @Override
+    public @NotNull PluginDescriptionFile getPluginDescription(@NotNull File file) throws InvalidDescriptionException {
+        try (JarFile jar = new JarFile(file)) {
+            PluginFileType<?, ?> type = PluginFileType.guessType(jar);
+            if (type == null) {
+                throw new InvalidDescriptionException(new FileNotFoundException("Jar does not contain plugin.yml"));
+            }
+
+            PluginMeta meta = type.getConfig(jar);
+            if (meta instanceof PluginDescriptionFile pluginDescriptionFile) {
+                return pluginDescriptionFile;
+            } else {
+                throw new InvalidDescriptionException("Plugin type does not use plugin.yml. Cannot read file description.");
+            }
+        } catch (Exception e) {
+            throw new InvalidDescriptionException(e);
+        }
+    }
+
+    @Override
+    public @NotNull Pattern[] getPluginFileFilters() {
+        return PATTERNS;
+    }
+
+    @Override
+    public @NotNull Map<Class<? extends Event>, Set<RegisteredListener>> createRegisteredListeners(@NotNull Listener listener, @NotNull Plugin plugin) {
+        return PaperPluginManagerImpl.getInstance().paperEventManager.createRegisteredListeners(listener, plugin);
+    }
+
+    @Override
+    public void enablePlugin(@NotNull Plugin plugin) {
+        Bukkit.getPluginManager().enablePlugin(plugin);
+    }
+
+    @Override
+    public void disablePlugin(@NotNull Plugin plugin) {
+        Bukkit.getPluginManager().disablePlugin(plugin);
+    }
+}

paper-server/src/main/java/io/papermc/paper/plugin/manager/MultiRuntimePluginProviderStorage.java

@@ -0,0 +1,61 @@
+package io.papermc.paper.plugin.manager;
+
+import com.mojang.logging.LogUtils;
+import io.papermc.paper.plugin.entrypoint.Entrypoint;
+import io.papermc.paper.plugin.entrypoint.LaunchEntryPointHandler;
+import io.papermc.paper.plugin.entrypoint.dependency.GraphDependencyContext;
+import io.papermc.paper.plugin.entrypoint.dependency.MetaDependencyTree;
+import io.papermc.paper.plugin.provider.PluginProvider;
+import io.papermc.paper.plugin.provider.type.paper.PaperPluginParent;
+import io.papermc.paper.plugin.storage.ServerPluginProviderStorage;
+import org.bukkit.plugin.java.JavaPlugin;
+import org.slf4j.Logger;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class MultiRuntimePluginProviderStorage extends ServerPluginProviderStorage {
+
+    private static final Logger LOGGER = LogUtils.getClassLogger();
+    private final List<JavaPlugin> provided = new ArrayList<>();
+
+    private final MetaDependencyTree dependencyTree;
+
+    MultiRuntimePluginProviderStorage(MetaDependencyTree dependencyTree) {
+        this.dependencyTree = dependencyTree;
+    }
+
+    @Override
+    public void register(PluginProvider<JavaPlugin> provider) {
+        if (provider instanceof PaperPluginParent.PaperServerPluginProvider) {
+            LOGGER.warn("Skipping loading of paper plugin requested from SimplePluginManager.");
+            return;
+        }
+        super.register(provider);
+        /*
+        Register the provider into the server entrypoint, this allows it to show in /plugins correctly. Generally it might be better in the future to make a separate storage,
+         as putting it into the entrypoint handlers doesn't make much sense.
+         */
+        LaunchEntryPointHandler.INSTANCE.register(Entrypoint.PLUGIN, provider);
+    }
+
+    @Override
+    public void processProvided(PluginProvider<JavaPlugin> provider, JavaPlugin provided) {
+        super.processProvided(provider, provided);
+        this.provided.add(provided);
+    }
+
+    @Override
+    public boolean throwOnCycle() {
+        return false;
+    }
+
+    public List<JavaPlugin> getLoaded() {
+        return this.provided;
+    }
+
+    @Override
+    public MetaDependencyTree createDependencyTree() {
+        return this.dependencyTree;
+    }
+}

paper-server/src/main/java/io/papermc/paper/plugin/manager/NormalPaperPermissionManager.java

@@ -0,0 +1,43 @@
+package io.papermc.paper.plugin.manager;
+
+import org.bukkit.permissions.Permissible;
+import org.bukkit.permissions.Permission;
+
+import java.util.HashMap;
+import java.util.LinkedHashMap;
+import java.util.LinkedHashSet;
+import java.util.Map;
+import java.util.Set;
+
+class NormalPaperPermissionManager extends PaperPermissionManager {
+
+    private final Map<String, Permission> permissions = new HashMap<>();
+    private final Map<Boolean, Set<Permission>> defaultPerms = new LinkedHashMap<>();
+    private final Map<String, Map<Permissible, Boolean>> permSubs = new HashMap<>();
+    private final Map<Boolean, Map<Permissible, Boolean>> defSubs = new HashMap<>();
+
+    public NormalPaperPermissionManager() {
+        this.defaultPerms().put(true, new LinkedHashSet<>());
+        this.defaultPerms().put(false, new LinkedHashSet<>());
+    }
+
+    @Override
+    public Map<String, Permission> permissions() {
+        return this.permissions;
+    }
+
+    @Override
+    public Map<Boolean, Set<Permission>> defaultPerms() {
+        return this.defaultPerms;
+    }
+
+    @Override
+    public Map<String, Map<Permissible, Boolean>> permSubs() {
+        return this.permSubs;
+    }
+
+    @Override
+    public Map<Boolean, Map<Permissible, Boolean>> defSubs() {
+        return this.defSubs;
+    }
+}

paper-server/src/main/java/io/papermc/paper/plugin/manager/PaperEventManager.java

@@ -0,0 +1,194 @@
+package io.papermc.paper.plugin.manager;
+
+import co.aikar.timings.TimedEventExecutor;
+import com.destroystokyo.paper.event.server.ServerExceptionEvent;
+import com.destroystokyo.paper.exception.ServerEventException;
+import com.google.common.collect.Sets;
+import org.bukkit.Server;
+import org.bukkit.Warning;
+import org.bukkit.event.Event;
+import org.bukkit.event.EventHandler;
+import org.bukkit.event.EventPriority;
+import org.bukkit.event.HandlerList;
+import org.bukkit.event.Listener;
+import org.bukkit.plugin.AuthorNagException;
+import org.bukkit.plugin.EventExecutor;
+import org.bukkit.plugin.IllegalPluginAccessException;
+import org.bukkit.plugin.Plugin;
+import org.bukkit.plugin.RegisteredListener;
+import org.jetbrains.annotations.NotNull;
+
+import java.lang.reflect.Method;
+import java.util.Arrays;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.Map;
+import java.util.Set;
+import java.util.logging.Level;
+
+class PaperEventManager {
+
+    private final Server server;
+
+    public PaperEventManager(Server server) {
+        this.server = server;
+    }
+
+    // SimplePluginManager
+    public void callEvent(@NotNull Event event) {
+        if (event.isAsynchronous() && this.server.isPrimaryThread()) {
+            throw new IllegalStateException(event.getEventName() + " may only be triggered asynchronously.");
+        } else if (!event.isAsynchronous() && !this.server.isPrimaryThread() && !this.server.isStopping()) {
+            throw new IllegalStateException(event.getEventName() + " may only be triggered synchronously.");
+        }
+
+        HandlerList handlers = event.getHandlers();
+        RegisteredListener[] listeners = handlers.getRegisteredListeners();
+
+        for (RegisteredListener registration : listeners) {
+            if (!registration.getPlugin().isEnabled()) {
+                continue;
+            }
+
+            try {
+                registration.callEvent(event);
+            } catch (AuthorNagException ex) {
+                Plugin plugin = registration.getPlugin();
+
+                if (plugin.isNaggable()) {
+                    plugin.setNaggable(false);
+
+                    this.server.getLogger().log(Level.SEVERE, String.format(
+                        "Nag author(s): '%s' of '%s' about the following: %s",
+                        plugin.getPluginMeta().getAuthors(),
+                        plugin.getPluginMeta().getDisplayName(),
+                        ex.getMessage()
+                    ));
+                }
+            } catch (Throwable ex) {
+                String msg = "Could not pass event " + event.getEventName() + " to " + registration.getPlugin().getPluginMeta().getDisplayName();
+                this.server.getLogger().log(Level.SEVERE, msg, ex);
+                if (!(event instanceof ServerExceptionEvent)) { // We don't want to cause an endless event loop
+                    this.callEvent(new ServerExceptionEvent(new ServerEventException(msg, ex, registration.getPlugin(), registration.getListener(), event)));
+                }
+            }
+        }
+    }
+
+    public void registerEvents(@NotNull Listener listener, @NotNull Plugin plugin) {
+        if (!plugin.isEnabled()) {
+            throw new IllegalPluginAccessException("Plugin attempted to register " + listener + " while not enabled");
+        }
+
+        for (Map.Entry<Class<? extends Event>, Set<RegisteredListener>> entry : this.createRegisteredListeners(listener, plugin).entrySet()) {
+            this.getEventListeners(this.getRegistrationClass(entry.getKey())).registerAll(entry.getValue());
+        }
+
+    }
+
+    public void registerEvent(@NotNull Class<? extends Event> event, @NotNull Listener listener, @NotNull EventPriority priority, @NotNull EventExecutor executor, @NotNull Plugin plugin) {
+        this.registerEvent(event, listener, priority, executor, plugin, false);
+    }
+
+    public void registerEvent(@NotNull Class<? extends Event> event, @NotNull Listener listener, @NotNull EventPriority priority, @NotNull EventExecutor executor, @NotNull Plugin plugin, boolean ignoreCancelled) {
+        if (!plugin.isEnabled()) {
+            throw new IllegalPluginAccessException("Plugin attempted to register " + event + " while not enabled");
+        }
+
+        executor = new TimedEventExecutor(executor, plugin, null, event);
+        this.getEventListeners(event).register(new RegisteredListener(listener, executor, priority, plugin, ignoreCancelled));
+    }
+
+    @NotNull
+    private HandlerList getEventListeners(@NotNull Class<? extends Event> type) {
+        try {
+            Method method = this.getRegistrationClass(type).getDeclaredMethod("getHandlerList");
+            method.setAccessible(true);
+            return (HandlerList) method.invoke(null);
+        } catch (Exception e) {
+            throw new IllegalPluginAccessException(e.toString());
+        }
+    }
+
+    @NotNull
+    private Class<? extends Event> getRegistrationClass(@NotNull Class<? extends Event> clazz) {
+        try {
+            clazz.getDeclaredMethod("getHandlerList");
+            return clazz;
+        } catch (NoSuchMethodException e) {
+            if (clazz.getSuperclass() != null
+                && !clazz.getSuperclass().equals(Event.class)
+                && Event.class.isAssignableFrom(clazz.getSuperclass())) {
+                return this.getRegistrationClass(clazz.getSuperclass().asSubclass(Event.class));
+            } else {
+                throw new IllegalPluginAccessException("Unable to find handler list for event " + clazz.getName() + ". Static getHandlerList method required!");
+            }
+        }
+    }
+
+    // JavaPluginLoader
+    @NotNull
+    public Map<Class<? extends Event>, Set<RegisteredListener>> createRegisteredListeners(@NotNull Listener listener, @NotNull final Plugin plugin) {
+        Map<Class<? extends Event>, Set<RegisteredListener>> ret = new HashMap<>();
+
+        Set<Method> methods;
+        try {
+            Class<?> listenerClazz = listener.getClass();
+            methods = Sets.union(
+                Set.of(listenerClazz.getMethods()),
+                Set.of(listenerClazz.getDeclaredMethods())
+            );
+        } catch (NoClassDefFoundError e) {
+            plugin.getLogger().severe("Failed to register events for " + listener.getClass() + " because " + e.getMessage() + " does not exist.");
+            return ret;
+        }
+
+        for (final Method method : methods) {
+            final EventHandler eh = method.getAnnotation(EventHandler.class);
+            if (eh == null) continue;
+            // Do not register bridge or synthetic methods to avoid event duplication
+            // Fixes SPIGOT-893
+            if (method.isBridge() || method.isSynthetic()) {
+                continue;
+            }
+            final Class<?> checkClass;
+            if (method.getParameterTypes().length != 1 || !Event.class.isAssignableFrom(checkClass = method.getParameterTypes()[0])) {
+                plugin.getLogger().severe(plugin.getPluginMeta().getDisplayName() + " attempted to register an invalid EventHandler method signature \"" + method.toGenericString() + "\" in " + listener.getClass());
+                continue;
+            }
+            final Class<? extends Event> eventClass = checkClass.asSubclass(Event.class);
+            method.setAccessible(true);
+            Set<RegisteredListener> eventSet = ret.computeIfAbsent(eventClass, k -> new HashSet<>());
+
+            for (Class<?> clazz = eventClass; Event.class.isAssignableFrom(clazz); clazz = clazz.getSuperclass()) {
+                // This loop checks for extending deprecated events
+                if (clazz.getAnnotation(Deprecated.class) != null) {
+                    Warning warning = clazz.getAnnotation(Warning.class);
+                    Warning.WarningState warningState = this.server.getWarningState();
+                    if (!warningState.printFor(warning)) {
+                        break;
+                    }
+                    plugin.getLogger().log(
+                        Level.WARNING,
+                        String.format(
+                            "\"%s\" has registered a listener for %s on method \"%s\", but the event is Deprecated. \"%s\"; please notify the authors %s.",
+                            plugin.getPluginMeta().getDisplayName(),
+                            clazz.getName(),
+                            method.toGenericString(),
+                            (warning != null && warning.reason().length() != 0) ? warning.reason() : "Server performance will be affected",
+                            Arrays.toString(plugin.getPluginMeta().getAuthors().toArray())),
+                        warningState == Warning.WarningState.ON ? new AuthorNagException(null) : null);
+                    break;
+                }
+            }
+
+            EventExecutor executor = new TimedEventExecutor(EventExecutor.create(method, eventClass), plugin, method, eventClass);
+            eventSet.add(new RegisteredListener(listener, executor, eh.priority(), plugin, eh.ignoreCancelled()));
+        }
+        return ret;
+    }
+
+    public void clearEvents() {
+        HandlerList.unregisterAll();
+    }
+}

paper-server/src/main/java/io/papermc/paper/plugin/manager/PaperPermissionManager.java

@@ -0,0 +1,201 @@
+package io.papermc.paper.plugin.manager;
+
+import com.google.common.collect.ImmutableSet;
+import io.papermc.paper.plugin.PermissionManager;
+import org.bukkit.permissions.Permissible;
+import org.bukkit.permissions.Permission;
+import org.bukkit.permissions.PermissionDefault;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.util.HashSet;
+import java.util.List;
+import java.util.Locale;
+import java.util.Map;
+import java.util.Set;
+import java.util.WeakHashMap;
+
+/**
+ * See
+ * {@link StupidSPMPermissionManagerWrapper}
+ */
+abstract class PaperPermissionManager implements PermissionManager {
+
+    public abstract Map<String, Permission> permissions();
+
+    public abstract Map<Boolean, Set<Permission>> defaultPerms();
+
+    public abstract Map<String, Map<Permissible, Boolean>> permSubs();
+
+    public abstract Map<Boolean, Map<Permissible, Boolean>> defSubs();
+
+    @Override
+    @Nullable
+    public Permission getPermission(@NotNull String name) {
+        return this.permissions().get(name.toLowerCase(java.util.Locale.ENGLISH));
+    }
+
+    @Override
+    public void addPermission(@NotNull Permission perm) {
+        this.addPermission(perm, true);
+    }
+
+    @Override
+    public void addPermissions(@NotNull List<Permission> permissions) {
+        for (Permission permission : permissions) {
+            this.addPermission(permission, false);
+        }
+        this.dirtyPermissibles();
+    }
+
+    // Allow suppressing permission default calculations
+    private void addPermission(@NotNull Permission perm, boolean dirty) {
+        String name = perm.getName().toLowerCase(java.util.Locale.ENGLISH);
+
+        if (this.permissions().containsKey(name)) {
+            throw new IllegalArgumentException("The permission " + name + " is already defined!");
+        }
+
+        this.permissions().put(name, perm);
+        this.calculatePermissionDefault(perm, dirty);
+    }
+
+    @Override
+    @NotNull
+    public Set<Permission> getDefaultPermissions(boolean op) {
+        return ImmutableSet.copyOf(this.defaultPerms().get(op));
+    }
+
+
+    @Override
+    public void removePermission(@NotNull Permission perm) {
+        this.removePermission(perm.getName());
+    }
+
+
+    @Override
+    public void removePermission(@NotNull String name) {
+        this.permissions().remove(name.toLowerCase(java.util.Locale.ENGLISH));
+    }
+
+    @Override
+    public void recalculatePermissionDefaults(@NotNull Permission perm) {
+        // we need a null check here because some plugins for some unknown reason pass null into this?
+        if (perm != null && this.permissions().containsKey(perm.getName().toLowerCase(Locale.ROOT))) {
+            this.defaultPerms().get(true).remove(perm);
+            this.defaultPerms().get(false).remove(perm);
+
+            this.calculatePermissionDefault(perm, true);
+        }
+    }
+
+    private void calculatePermissionDefault(@NotNull Permission perm, boolean dirty) {
+        if ((perm.getDefault() == PermissionDefault.OP) || (perm.getDefault() == PermissionDefault.TRUE)) {
+            this.defaultPerms().get(true).add(perm);
+            if (dirty) {
+                this.dirtyPermissibles(true);
+            }
+        }
+        if ((perm.getDefault() == PermissionDefault.NOT_OP) || (perm.getDefault() == PermissionDefault.TRUE)) {
+            this.defaultPerms().get(false).add(perm);
+            if (dirty) {
+                this.dirtyPermissibles(false);
+            }
+        }
+    }
+
+
+    @Override
+    public void subscribeToPermission(@NotNull String permission, @NotNull Permissible permissible) {
+        String name = permission.toLowerCase(java.util.Locale.ENGLISH);
+        Map<Permissible, Boolean> map = this.permSubs().computeIfAbsent(name, k -> new WeakHashMap<>());
+
+        map.put(permissible, true);
+    }
+
+    @Override
+    public void unsubscribeFromPermission(@NotNull String permission, @NotNull Permissible permissible) {
+        String name = permission.toLowerCase(java.util.Locale.ENGLISH);
+        Map<Permissible, Boolean> map = this.permSubs().get(name);
+
+        if (map != null) {
+            map.remove(permissible);
+
+            if (map.isEmpty()) {
+                this.permSubs().remove(name);
+            }
+        }
+    }
+
+    @Override
+    @NotNull
+    public Set<Permissible> getPermissionSubscriptions(@NotNull String permission) {
+        String name = permission.toLowerCase(java.util.Locale.ENGLISH);
+        Map<Permissible, Boolean> map = this.permSubs().get(name);
+
+        if (map == null) {
+            return ImmutableSet.of();
+        } else {
+            return ImmutableSet.copyOf(map.keySet());
+        }
+    }
+
+    @Override
+    public void subscribeToDefaultPerms(boolean op, @NotNull Permissible permissible) {
+        Map<Permissible, Boolean> map = this.defSubs().computeIfAbsent(op, k -> new WeakHashMap<>());
+
+        map.put(permissible, true);
+    }
+
+    @Override
+    public void unsubscribeFromDefaultPerms(boolean op, @NotNull Permissible permissible) {
+        Map<Permissible, Boolean> map = this.defSubs().get(op);
+
+        if (map != null) {
+            map.remove(permissible);
+
+            if (map.isEmpty()) {
+                this.defSubs().remove(op);
+            }
+        }
+    }
+
+    @Override
+    @NotNull
+    public Set<Permissible> getDefaultPermSubscriptions(boolean op) {
+        Map<Permissible, Boolean> map = this.defSubs().get(op);
+
+        if (map == null) {
+            return ImmutableSet.of();
+        } else {
+            return ImmutableSet.copyOf(map.keySet());
+        }
+    }
+
+    @Override
+    @NotNull
+    public Set<Permission> getPermissions() {
+        return new HashSet<>(this.permissions().values());
+    }
+
+    @Override
+    public void clearPermissions() {
+        this.permissions().clear();
+        this.defaultPerms().get(true).clear();
+        this.defaultPerms().get(false).clear();
+    }
+
+
+    void dirtyPermissibles(boolean op) {
+        Set<Permissible> permissibles = this.getDefaultPermSubscriptions(op);
+
+        for (Permissible p : permissibles) {
+            p.recalculatePermissions();
+        }
+    }
+
+    void dirtyPermissibles() {
+        this.dirtyPermissibles(true);
+        this.dirtyPermissibles(false);
+    }
+}

paper-server/src/main/java/io/papermc/paper/plugin/manager/PaperPluginInstanceManager.java

@@ -0,0 +1,317 @@
+package io.papermc.paper.plugin.manager;
+
+import com.google.common.base.Preconditions;
+import com.google.common.graph.GraphBuilder;
+import com.google.common.graph.MutableGraph;
+import io.papermc.paper.plugin.configuration.PluginMeta;
+import io.papermc.paper.plugin.entrypoint.Entrypoint;
+import io.papermc.paper.plugin.entrypoint.dependency.MetaDependencyTree;
+import io.papermc.paper.plugin.entrypoint.dependency.SimpleMetaDependencyTree;
+import io.papermc.paper.plugin.entrypoint.strategy.PluginGraphCycleException;
+import io.papermc.paper.plugin.provider.classloader.ConfiguredPluginClassLoader;
+import io.papermc.paper.plugin.provider.classloader.PaperClassLoaderStorage;
+import io.papermc.paper.plugin.provider.source.DirectoryProviderSource;
+import io.papermc.paper.plugin.provider.source.FileArrayProviderSource;
+import io.papermc.paper.plugin.provider.source.FileProviderSource;
+import java.io.File;
+import org.bukkit.Bukkit;
+import org.bukkit.Server;
+import org.bukkit.World;
+import org.bukkit.command.Command;
+import org.bukkit.command.CommandMap;
+import org.bukkit.command.PluginCommandYamlParser;
+import org.bukkit.craftbukkit.util.CraftMagicNumbers;
+import org.bukkit.event.HandlerList;
+import org.bukkit.event.server.PluginDisableEvent;
+import org.bukkit.event.server.PluginEnableEvent;
+import org.bukkit.plugin.InvalidPluginException;
+import org.bukkit.plugin.Plugin;
+import org.bukkit.plugin.PluginDescriptionFile;
+import org.bukkit.plugin.PluginManager;
+import org.bukkit.plugin.UnknownDependencyException;
+import org.bukkit.plugin.java.JavaPlugin;
+import org.jetbrains.annotations.ApiStatus;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.logging.Level;
+
+@SuppressWarnings("UnstableApiUsage")
+class PaperPluginInstanceManager {
+
+    private static final FileProviderSource FILE_PROVIDER_SOURCE = new FileProviderSource("File '%s'"::formatted);
+
+    private final List<Plugin> plugins = new ArrayList<>();
+    private final Map<String, Plugin> lookupNames = new HashMap<>();
+
+    private final PluginManager pluginManager;
+    private final CommandMap commandMap;
+    private final Server server;
+
+    private final MetaDependencyTree dependencyTree = new SimpleMetaDependencyTree(GraphBuilder.directed().build());
+
+    public PaperPluginInstanceManager(PluginManager pluginManager, CommandMap commandMap, Server server) {
+        this.commandMap = commandMap;
+        this.server = server;
+        this.pluginManager = pluginManager;
+    }
+
+    public @Nullable Plugin getPlugin(@NotNull String name) {
+        return this.lookupNames.get(name.replace(' ', '_').toLowerCase(java.util.Locale.ENGLISH)); // Paper
+    }
+
+    public @NotNull Plugin[] getPlugins() {
+        return this.plugins.toArray(new Plugin[0]);
+    }
+
+    public boolean isPluginEnabled(@NotNull String name) {
+        Plugin plugin = this.getPlugin(name);
+
+        return this.isPluginEnabled(plugin);
+    }
+
+    public synchronized boolean isPluginEnabled(@Nullable Plugin plugin) {
+        if ((plugin != null) && (this.plugins.contains(plugin))) {
+            return plugin.isEnabled();
+        } else {
+            return false;
+        }
+    }
+
+    public void loadPlugin(Plugin provided) {
+        PluginMeta configuration = provided.getPluginMeta();
+
+        this.plugins.add(provided);
+        this.lookupNames.put(configuration.getName().toLowerCase(java.util.Locale.ENGLISH), provided);
+        for (String providedPlugin : configuration.getProvidedPlugins()) {
+            this.lookupNames.putIfAbsent(providedPlugin.toLowerCase(java.util.Locale.ENGLISH), provided);
+        }
+
+        this.dependencyTree.add(configuration);
+    }
+
+    // InvalidDescriptionException is never used, because the old JavaPluginLoader would wrap the exception.
+    public @Nullable Plugin loadPlugin(@NotNull Path path) throws InvalidPluginException, UnknownDependencyException {
+        RuntimePluginEntrypointHandler<SingularRuntimePluginProviderStorage> runtimePluginEntrypointHandler = new RuntimePluginEntrypointHandler<>(new SingularRuntimePluginProviderStorage(this.dependencyTree));
+
+        try {
+            path = FILE_PROVIDER_SOURCE.prepareContext(path);
+            FILE_PROVIDER_SOURCE.registerProviders(runtimePluginEntrypointHandler, path);
+        } catch (IllegalArgumentException exception) {
+            return null; // Return null when the plugin file is not valid / plugin type is unknown
+        } catch (PluginGraphCycleException exception) {
+            throw new InvalidPluginException("Cannot import plugin that causes cyclic dependencies!");
+        } catch (Exception e) {
+            throw new InvalidPluginException(e);
+        }
+
+        try {
+            runtimePluginEntrypointHandler.enter(Entrypoint.PLUGIN);
+        } catch (Throwable e) {
+            throw new InvalidPluginException(e);
+        }
+
+        return runtimePluginEntrypointHandler.getPluginProviderStorage().getSingleLoaded()
+            .orElseThrow(() -> new InvalidPluginException("Plugin didn't load any plugin providers?"));
+    }
+
+    public @NotNull Plugin[] loadPlugins(@NotNull File[] files) {
+        RuntimePluginEntrypointHandler<MultiRuntimePluginProviderStorage> runtimePluginEntrypointHandler = new RuntimePluginEntrypointHandler<>(new MultiRuntimePluginProviderStorage(this.dependencyTree));
+        try {
+            List<Path> paths = FileArrayProviderSource.INSTANCE.prepareContext(files);
+            DirectoryProviderSource.INSTANCE.registerProviders(runtimePluginEntrypointHandler, paths);
+            runtimePluginEntrypointHandler.enter(Entrypoint.PLUGIN);
+        } catch (Exception e) {
+            // This should never happen, any errors that occur in this provider should instead be logged.
+            this.server.getLogger().log(Level.SEVERE, "Unknown error occurred while loading plugins through PluginManager.", e);
+        }
+
+        return runtimePluginEntrypointHandler.getPluginProviderStorage().getLoaded().toArray(new JavaPlugin[0]);
+    }
+
+    // The behavior of this is that all errors are logged instead of being thrown
+    public @NotNull Plugin[] loadPlugins(@NotNull Path directory) {
+        Preconditions.checkArgument(Files.isDirectory(directory), "Directory must be a directory"); // Avoid creating a directory if it doesn't exist
+
+        RuntimePluginEntrypointHandler<MultiRuntimePluginProviderStorage> runtimePluginEntrypointHandler = new RuntimePluginEntrypointHandler<>(new MultiRuntimePluginProviderStorage(this.dependencyTree));
+        try {
+            List<Path> files = DirectoryProviderSource.INSTANCE.prepareContext(directory);
+            DirectoryProviderSource.INSTANCE.registerProviders(runtimePluginEntrypointHandler, files);
+            runtimePluginEntrypointHandler.enter(Entrypoint.PLUGIN);
+        } catch (Exception e) {
+            // This should never happen, any errors that occur in this provider should instead be logged.
+            this.server.getLogger().log(Level.SEVERE, "Unknown error occurred while loading plugins through PluginManager.", e);
+        }
+
+        return runtimePluginEntrypointHandler.getPluginProviderStorage().getLoaded().toArray(new JavaPlugin[0]);
+    }
+
+    // Plugins are disabled in order like this inorder to "rougly" prevent
+    // their dependencies unloading first. But, eh.
+    public void disablePlugins() {
+        Plugin[] plugins = this.getPlugins();
+        for (int i = plugins.length - 1; i >= 0; i--) {
+            this.disablePlugin(plugins[i]);
+        }
+    }
+
+    public void clearPlugins() {
+        synchronized (this) {
+            this.disablePlugins();
+            this.plugins.clear();
+            this.lookupNames.clear();
+        }
+    }
+
+    public synchronized void enablePlugin(@NotNull Plugin plugin) {
+        if (plugin.isEnabled()) {
+            return;
+        }
+
+        if (plugin.getPluginMeta() instanceof PluginDescriptionFile) {
+            List<Command> bukkitCommands = PluginCommandYamlParser.parse(plugin);
+
+            if (!bukkitCommands.isEmpty()) {
+                this.commandMap.registerAll(plugin.getPluginMeta().getName(), bukkitCommands);
+            }
+        }
+
+        try {
+            String enableMsg = "Enabling " + plugin.getPluginMeta().getDisplayName();
+            if (plugin.getPluginMeta() instanceof PluginDescriptionFile descriptionFile && CraftMagicNumbers.isLegacy(descriptionFile)) {
+                enableMsg += "*";
+            }
+            plugin.getLogger().info(enableMsg);
+
+            JavaPlugin jPlugin = (JavaPlugin) plugin;
+
+            if (jPlugin.getClass().getClassLoader() instanceof ConfiguredPluginClassLoader classLoader) { // Paper
+                if (PaperClassLoaderStorage.instance().registerUnsafePlugin(classLoader)) {
+                    this.server.getLogger().log(Level.WARNING, "Enabled plugin with unregistered ConfiguredPluginClassLoader " + plugin.getPluginMeta().getDisplayName());
+                }
+            } // Paper
+
+            try {
+                jPlugin.setEnabled(true);
+            } catch (Throwable ex) {
+                this.server.getLogger().log(Level.SEVERE, "Error occurred while enabling " + plugin.getPluginMeta().getDisplayName() + " (Is it up to date?)", ex);
+                // Paper start - Disable plugins that fail to load
+                this.server.getPluginManager().disablePlugin(jPlugin);
+                return;
+                // Paper end
+            }
+
+            // Perhaps abort here, rather than continue going, but as it stands,
+            // an abort is not possible the way it's currently written
+            this.server.getPluginManager().callEvent(new PluginEnableEvent(plugin));
+        } catch (Throwable ex) {
+            this.handlePluginException("Error occurred (in the plugin loader) while enabling "
+                + plugin.getPluginMeta().getDisplayName() + " (Is it up to date?)", ex, plugin);
+        }
+
+        HandlerList.bakeAll();
+    }
+
+    public synchronized void disablePlugin(@NotNull Plugin plugin) {
+        if (!(plugin instanceof JavaPlugin javaPlugin)) {
+            throw new IllegalArgumentException("Only expects java plugins.");
+        }
+        if (!plugin.isEnabled()) {
+            return;
+        }
+
+        String pluginName = plugin.getPluginMeta().getDisplayName();
+
+        try {
+            plugin.getLogger().info("Disabling %s".formatted(pluginName));
+
+            this.server.getPluginManager().callEvent(new PluginDisableEvent(plugin));
+            try {
+                javaPlugin.setEnabled(false);
+            } catch (Throwable ex) {
+                this.server.getLogger().log(Level.SEVERE, "Error occurred while disabling " + pluginName, ex);
+            }
+
+            ClassLoader classLoader = plugin.getClass().getClassLoader();
+            if (classLoader instanceof ConfiguredPluginClassLoader configuredPluginClassLoader) {
+                try {
+                    configuredPluginClassLoader.close();
+                } catch (IOException ex) {
+                    this.server.getLogger().log(Level.WARNING, "Error closing the classloader for '" + pluginName + "'", ex); // Paper - log exception
+                }
+                // Remove from the classloader pool inorder to prevent plugins from trying
+                // to access classes
+                PaperClassLoaderStorage.instance().unregisterClassloader(configuredPluginClassLoader);
+            }
+
+        } catch (Throwable ex) {
+            this.handlePluginException("Error occurred (in the plugin loader) while disabling "
+                + pluginName + " (Is it up to date?)", ex, plugin); // Paper
+        }
+
+        try {
+            this.server.getScheduler().cancelTasks(plugin);
+        } catch (Throwable ex) {
+            this.handlePluginException("Error occurred (in the plugin loader) while cancelling tasks for "
+                + pluginName + " (Is it up to date?)", ex, plugin); // Paper
+        }
+
+        try {
+            this.server.getServicesManager().unregisterAll(plugin);
+        } catch (Throwable ex) {
+            this.handlePluginException("Error occurred (in the plugin loader) while unregistering services for "
+                + pluginName + " (Is it up to date?)", ex, plugin); // Paper
+        }
+
+        try {
+            HandlerList.unregisterAll(plugin);
+        } catch (Throwable ex) {
+            this.handlePluginException("Error occurred (in the plugin loader) while unregistering events for "
+                + pluginName + " (Is it up to date?)", ex, plugin); // Paper
+        }
+
+        try {
+            this.server.getMessenger().unregisterIncomingPluginChannel(plugin);
+            this.server.getMessenger().unregisterOutgoingPluginChannel(plugin);
+        } catch (Throwable ex) {
+            this.handlePluginException("Error occurred (in the plugin loader) while unregistering plugin channels for "
+                + pluginName + " (Is it up to date?)", ex, plugin); // Paper
+        }
+
+        try {
+            for (World world : this.server.getWorlds()) {
+                world.removePluginChunkTickets(plugin);
+            }
+        } catch (Throwable ex) {
+            this.handlePluginException("Error occurred (in the plugin loader) while removing chunk tickets for " + pluginName + " (Is it up to date?)", ex, plugin); // Paper
+        }
+
+    }
+
+    // TODO: Implement event part in future patch (paper patch move up, this patch is lower)
+    private void handlePluginException(String msg, Throwable ex, Plugin plugin) {
+        Bukkit.getServer().getLogger().log(Level.SEVERE, msg, ex);
+        this.pluginManager.callEvent(new com.destroystokyo.paper.event.server.ServerExceptionEvent(new com.destroystokyo.paper.exception.ServerPluginEnableDisableException(msg, ex, plugin)));
+    }
+
+    public boolean isTransitiveDepend(@NotNull PluginMeta plugin, @NotNull PluginMeta depend) {
+        return this.dependencyTree.isTransitiveDependency(plugin, depend);
+    }
+
+    public boolean hasDependency(String pluginIdentifier) {
+        return this.getPlugin(pluginIdentifier) != null;
+    }
+
+    // Debug only
+    @ApiStatus.Internal
+    public MutableGraph<String> getDependencyGraph() {
+        return this.dependencyTree.getGraph();
+    }
+}

paper-server/src/main/java/io/papermc/paper/plugin/manager/PaperPluginManagerImpl.java

@@ -0,0 +1,246 @@
+package io.papermc.paper.plugin.manager;
+
+import com.google.common.graph.MutableGraph;
+import io.papermc.paper.plugin.PermissionManager;
+import io.papermc.paper.plugin.configuration.PluginMeta;
+import io.papermc.paper.plugin.provider.entrypoint.DependencyContext;
+import org.bukkit.Bukkit;
+import org.bukkit.Server;
+import org.bukkit.command.CommandMap;
+import org.bukkit.craftbukkit.CraftServer;
+import org.bukkit.event.Event;
+import org.bukkit.event.EventPriority;
+import org.bukkit.event.Listener;
+import org.bukkit.permissions.Permissible;
+import org.bukkit.permissions.Permission;
+import org.bukkit.plugin.EventExecutor;
+import org.bukkit.plugin.InvalidDescriptionException;
+import org.bukkit.plugin.InvalidPluginException;
+import org.bukkit.plugin.Plugin;
+import org.bukkit.plugin.PluginLoader;
+import org.bukkit.plugin.PluginManager;
+import org.bukkit.plugin.SimplePluginManager;
+import org.bukkit.plugin.UnknownDependencyException;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.io.File;
+import java.util.List;
+import java.util.Set;
+
+public class PaperPluginManagerImpl implements PluginManager, DependencyContext {
+
+    final PaperPluginInstanceManager instanceManager;
+    final PaperEventManager paperEventManager;
+    PermissionManager permissionManager;
+
+    public PaperPluginManagerImpl(Server server, CommandMap commandMap, @Nullable SimplePluginManager permissionManager) {
+        this.instanceManager = new PaperPluginInstanceManager(this, commandMap, server);
+        this.paperEventManager = new PaperEventManager(server);
+
+        if (permissionManager == null) {
+            this.permissionManager = new NormalPaperPermissionManager();
+        } else {
+            this.permissionManager = new StupidSPMPermissionManagerWrapper(permissionManager); // TODO: See comment when SimplePermissionManager is removed
+        }
+    }
+
+    // REMOVE THIS WHEN SimplePluginManager is removed.
+    // Just cast and use Bukkit.getServer().getPluginManager()
+    public static PaperPluginManagerImpl getInstance() {
+        return ((CraftServer) (Bukkit.getServer())).paperPluginManager;
+    }
+
+    // Plugin Manipulation
+
+    @Override
+    public @Nullable Plugin getPlugin(@NotNull String name) {
+        return this.instanceManager.getPlugin(name);
+    }
+
+    @Override
+    public @NotNull Plugin[] getPlugins() {
+        return this.instanceManager.getPlugins();
+    }
+
+    @Override
+    public boolean isPluginEnabled(@NotNull String name) {
+        return this.instanceManager.isPluginEnabled(name);
+    }
+
+    @Override
+    public boolean isPluginEnabled(@Nullable Plugin plugin) {
+        return this.instanceManager.isPluginEnabled(plugin);
+    }
+
+    public void loadPlugin(Plugin plugin) {
+        this.instanceManager.loadPlugin(plugin);
+    }
+
+    @Override
+    public @Nullable Plugin loadPlugin(@NotNull File file) throws InvalidPluginException, InvalidDescriptionException, UnknownDependencyException {
+        return this.instanceManager.loadPlugin(file.toPath());
+    }
+
+    @Override
+    public @NotNull Plugin[] loadPlugins(@NotNull File directory) {
+        return this.instanceManager.loadPlugins(directory.toPath());
+    }
+
+    @Override
+    public @NotNull Plugin[] loadPlugins(final @NotNull File[] files) {
+        return this.instanceManager.loadPlugins(files);
+    }
+
+    @Override
+    public void disablePlugins() {
+        this.instanceManager.disablePlugins();
+    }
+
+    @Override
+    public synchronized void clearPlugins() {
+        this.instanceManager.clearPlugins();
+        this.permissionManager.clearPermissions();
+        this.paperEventManager.clearEvents();
+    }
+
+    @Override
+    public void enablePlugin(@NotNull Plugin plugin) {
+        this.instanceManager.enablePlugin(plugin);
+    }
+
+    @Override
+    public void disablePlugin(@NotNull Plugin plugin) {
+        this.instanceManager.disablePlugin(plugin);
+    }
+
+    @Override
+    public boolean isTransitiveDependency(PluginMeta pluginMeta, PluginMeta dependencyConfig) {
+        return this.instanceManager.isTransitiveDepend(pluginMeta, dependencyConfig);
+    }
+
+    @Override
+    public boolean hasDependency(String pluginIdentifier) {
+        return this.instanceManager.hasDependency(pluginIdentifier);
+    }
+
+    // Event manipulation
+
+    @Override
+    public void callEvent(@NotNull Event event) throws IllegalStateException {
+        this.paperEventManager.callEvent(event);
+    }
+
+    @Override
+    public void registerEvents(@NotNull Listener listener, @NotNull Plugin plugin) {
+        this.paperEventManager.registerEvents(listener, plugin);
+    }
+
+    @Override
+    public void registerEvent(@NotNull Class<? extends Event> event, @NotNull Listener listener, @NotNull EventPriority priority, @NotNull EventExecutor executor, @NotNull Plugin plugin) {
+        this.paperEventManager.registerEvent(event, listener, priority, executor, plugin);
+    }
+
+    @Override
+    public void registerEvent(@NotNull Class<? extends Event> event, @NotNull Listener listener, @NotNull EventPriority priority, @NotNull EventExecutor executor, @NotNull Plugin plugin, boolean ignoreCancelled) {
+        this.paperEventManager.registerEvent(event, listener, priority, executor, plugin, ignoreCancelled);
+    }
+
+    // Permission manipulation
+
+    @Override
+    public @Nullable Permission getPermission(@NotNull String name) {
+        return this.permissionManager.getPermission(name);
+    }
+
+    @Override
+    public void addPermission(@NotNull Permission perm) {
+        this.permissionManager.addPermission(perm);
+    }
+
+    @Override
+    public void removePermission(@NotNull Permission perm) {
+        this.permissionManager.removePermission(perm);
+    }
+
+    @Override
+    public void removePermission(@NotNull String name) {
+        this.permissionManager.removePermission(name);
+    }
+
+    @Override
+    public @NotNull Set<Permission> getDefaultPermissions(boolean op) {
+        return this.permissionManager.getDefaultPermissions(op);
+    }
+
+    @Override
+    public void recalculatePermissionDefaults(@NotNull Permission perm) {
+        this.permissionManager.recalculatePermissionDefaults(perm);
+    }
+
+    @Override
+    public void subscribeToPermission(@NotNull String permission, @NotNull Permissible permissible) {
+        this.permissionManager.subscribeToPermission(permission, permissible);
+    }
+
+    @Override
+    public void unsubscribeFromPermission(@NotNull String permission, @NotNull Permissible permissible) {
+        this.permissionManager.unsubscribeFromPermission(permission, permissible);
+    }
+
+    @Override
+    public @NotNull Set<Permissible> getPermissionSubscriptions(@NotNull String permission) {
+        return this.permissionManager.getPermissionSubscriptions(permission);
+    }
+
+    @Override
+    public void subscribeToDefaultPerms(boolean op, @NotNull Permissible permissible) {
+        this.permissionManager.subscribeToDefaultPerms(op, permissible);
+    }
+
+    @Override
+    public void unsubscribeFromDefaultPerms(boolean op, @NotNull Permissible permissible) {
+        this.permissionManager.unsubscribeFromDefaultPerms(op, permissible);
+    }
+
+    @Override
+    public @NotNull Set<Permissible> getDefaultPermSubscriptions(boolean op) {
+        return this.permissionManager.getDefaultPermSubscriptions(op);
+    }
+
+    @Override
+    public @NotNull Set<Permission> getPermissions() {
+        return this.permissionManager.getPermissions();
+    }
+
+    @Override
+    public void addPermissions(@NotNull List<Permission> perm) {
+        this.permissionManager.addPermissions(perm);
+    }
+
+    @Override
+    public void clearPermissions() {
+        this.permissionManager.clearPermissions();
+    }
+
+    @Override
+    public void overridePermissionManager(@NotNull Plugin plugin, @Nullable PermissionManager permissionManager) {
+        this.permissionManager = permissionManager;
+    }
+
+    // Etc
+
+    @Override
+    public boolean useTimings() {
+        return co.aikar.timings.Timings.isTimingsEnabled();
+    }
+
+    @Override
+    public void registerInterface(@NotNull Class<? extends PluginLoader> loader) throws IllegalArgumentException {
+        throw new UnsupportedOperationException();
+    }
+
+    public MutableGraph<String> getInstanceManagerGraph() {
+        return instanceManager.getDependencyGraph();
+    }
+}

paper-server/src/main/java/io/papermc/paper/plugin/manager/RuntimePluginEntrypointHandler.java

@@ -0,0 +1,47 @@
+package io.papermc.paper.plugin.manager;
+
+import com.destroystokyo.paper.util.SneakyThrow;
+import io.papermc.paper.plugin.entrypoint.Entrypoint;
+import io.papermc.paper.plugin.entrypoint.EntrypointHandler;
+import io.papermc.paper.plugin.provider.PluginProvider;
+import io.papermc.paper.plugin.storage.ProviderStorage;
+import org.bukkit.plugin.InvalidPluginException;
+import org.bukkit.plugin.java.JavaPlugin;
+import org.jetbrains.annotations.NotNull;
+
+/**
+ * Used for loading plugins during runtime, only supporting providers that are plugins.
+ * This is only used for the plugin manager, as it only allows plugins to be
+ * registered to a provider storage.
+ */
+class RuntimePluginEntrypointHandler<T extends ProviderStorage<JavaPlugin>> implements EntrypointHandler {
+
+    private final T providerStorage;
+
+    RuntimePluginEntrypointHandler(T providerStorage) {
+        this.providerStorage = providerStorage;
+    }
+
+    @Override
+    public <T> void register(Entrypoint<T> entrypoint, PluginProvider<T> provider) {
+        if (!entrypoint.equals(Entrypoint.PLUGIN)) {
+            SneakyThrow.sneaky(new InvalidPluginException("Plugin cannot register entrypoints other than PLUGIN during runtime. Tried registering %s!".formatted(entrypoint)));
+            // We have to throw an invalid plugin exception for legacy reasons
+        }
+
+        this.providerStorage.register((PluginProvider<JavaPlugin>) provider);
+    }
+
+    @Override
+    public void enter(Entrypoint<?> entrypoint) {
+        if (entrypoint != Entrypoint.PLUGIN) {
+            throw new IllegalArgumentException("Only plugin entrypoint supported");
+        }
+        this.providerStorage.enter();
+    }
+
+    @NotNull
+    public T getPluginProviderStorage() {
+        return this.providerStorage;
+    }
+}

paper-server/src/main/java/io/papermc/paper/plugin/manager/SingularRuntimePluginProviderStorage.java

@@ -0,0 +1,79 @@
+package io.papermc.paper.plugin.manager;
+
+import com.destroystokyo.paper.util.SneakyThrow;
+import io.papermc.paper.plugin.entrypoint.Entrypoint;
+import io.papermc.paper.plugin.entrypoint.LaunchEntryPointHandler;
+import io.papermc.paper.plugin.entrypoint.dependency.GraphDependencyContext;
+import io.papermc.paper.plugin.entrypoint.dependency.MetaDependencyTree;
+import io.papermc.paper.plugin.provider.PluginProvider;
+import io.papermc.paper.plugin.provider.type.paper.PaperPluginParent;
+import io.papermc.paper.plugin.storage.ServerPluginProviderStorage;
+import org.bukkit.plugin.InvalidPluginException;
+import org.bukkit.plugin.PluginDescriptionFile;
+import org.bukkit.plugin.UnknownDependencyException;
+import org.bukkit.plugin.java.JavaPlugin;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Optional;
+
+/**
+ * Used for registering a single plugin provider.
+ * This has special behavior in that some errors are thrown instead of logged.
+ */
+class SingularRuntimePluginProviderStorage extends ServerPluginProviderStorage {
+
+    private final MetaDependencyTree dependencyTree;
+    private PluginProvider<JavaPlugin> lastProvider;
+    private JavaPlugin singleLoaded;
+
+    SingularRuntimePluginProviderStorage(MetaDependencyTree dependencyTree) {
+        this.dependencyTree = dependencyTree;
+    }
+
+    @Override
+    public void register(PluginProvider<JavaPlugin> provider) {
+        super.register(provider);
+        if (this.lastProvider != null) {
+            SneakyThrow.sneaky(new InvalidPluginException("Plugin registered two JavaPlugins"));
+        }
+        if (provider instanceof PaperPluginParent.PaperServerPluginProvider) {
+            throw new IllegalStateException("Cannot register paper plugins during runtime!");
+        }
+        this.lastProvider = provider;
+        // Register the provider into the server entrypoint, this allows it to show in /plugins correctly.
+        // Generally it might be better in the future to make a separate storage, as putting it into the entrypoint handlers doesn't make much sense.
+        LaunchEntryPointHandler.INSTANCE.register(Entrypoint.PLUGIN, provider);
+    }
+
+    @Override
+    public void enter() {
+        PluginProvider<JavaPlugin> provider = this.lastProvider;
+        if (provider == null) {
+            return;
+        }
+
+        // Go through normal plugin loading logic
+        super.enter();
+    }
+
+    @Override
+    public void processProvided(PluginProvider<JavaPlugin> provider, JavaPlugin provided) {
+        super.processProvided(provider, provided);
+        this.singleLoaded = provided;
+    }
+
+    @Override
+    public boolean throwOnCycle() {
+        return false;
+    }
+
+    public Optional<JavaPlugin> getSingleLoaded() {
+        return Optional.ofNullable(this.singleLoaded);
+    }
+
+    @Override
+    public MetaDependencyTree createDependencyTree() {
+        return this.dependencyTree;
+    }
+}

paper-server/src/main/java/io/papermc/paper/plugin/manager/StupidSPMPermissionManagerWrapper.java

@@ -0,0 +1,42 @@
+package io.papermc.paper.plugin.manager;
+
+import org.bukkit.permissions.Permissible;
+import org.bukkit.permissions.Permission;
+import org.bukkit.plugin.SimplePluginManager;
+
+import java.util.Map;
+import java.util.Set;
+
+/*
+This is actually so cursed I hate it.
+We need to wrap these in fields as people override the fields, so we need to access them lazily at all times.
+// TODO: When SimplePluginManager is GONE remove this and cleanup the PaperPermissionManager to use actual fields.
+ */
+class StupidSPMPermissionManagerWrapper extends PaperPermissionManager {
+
+    private final SimplePluginManager simplePluginManager;
+
+    public StupidSPMPermissionManagerWrapper(SimplePluginManager simplePluginManager) {
+        this.simplePluginManager = simplePluginManager;
+    }
+
+    @Override
+    public Map<String, Permission> permissions() {
+        return this.simplePluginManager.permissions;
+    }
+
+    @Override
+    public Map<Boolean, Set<Permission>> defaultPerms() {
+        return this.simplePluginManager.defaultPerms;
+    }
+
+    @Override
+    public Map<String, Map<Permissible, Boolean>> permSubs() {
+        return this.simplePluginManager.permSubs;
+    }
+
+    @Override
+    public Map<Boolean, Map<Permissible, Boolean>> defSubs() {
+        return this.simplePluginManager.defSubs;
+    }
+}