Added dynamic loading functionality, Updated API to v3.1.0

2 files changed, 214 insertions, 31 deletions

diff --git a/src/com/redstoner/coremods/moduleLoader/ModuleLoader.java b/src/com/redstoner/coremods/moduleLoader/ModuleLoader.java
index ab0e3ec..cf1dd98 100644
--- a/src/com/redstoner/coremods/moduleLoader/ModuleLoader.java
+++ b/src/com/redstoner/coremods/moduleLoader/ModuleLoader.java
@@ -1,9 +1,14 @@
 package com.redstoner.coremods.moduleLoader;
 
 import java.io.File;
+import java.io.IOException;
+import java.net.MalformedURLException;
+import java.net.URL;
+import java.net.URLClassLoader;
 import java.util.HashMap;
 
 import org.bukkit.Bukkit;
+import org.bukkit.World;
 import org.bukkit.command.CommandSender;
 import org.bukkit.event.HandlerList;
 import org.bukkit.event.Listener;
@@ -22,6 +27,8 @@ import com.redstoner.misc.VersionHelper;
 import com.redstoner.modules.CoreModule;
 import com.redstoner.modules.Module;
 
+import net.minecraft.server.v1_11_R1.MinecraftServer;
+
 /** The module loader, mother of all modules. Responsible for loading and taking care of all modules.
  * 
  * @author Pepich */
@@ -30,9 +37,21 @@ public final class ModuleLoader implements CoreModule
 {
 	private static ModuleLoader instance;
 	private static final HashMap<Module, Boolean> modules = new HashMap<Module, Boolean>();
+	private static URL[] urls;
+	private static URLClassLoader mainLoader;
 	
 	private ModuleLoader()
-	{}
+	{
+		try
+		{
+			urls = new URL[] {(new File(Main.plugin.getDataFolder(), "classes")).toURI().toURL()};
+			mainLoader = new URLClassLoader(urls, this.getClass().getClassLoader());
+		}
+		catch (MalformedURLException e)
+		{
+			System.out.println("Sumtin is wong with ya filesüstem m8. Fix eeeet or I won't werk!");
+		}
+	}
 	
 	public static void init()
 	{
@@ -42,10 +61,12 @@ public final class ModuleLoader implements CoreModule
 				Main.plugin);
 	}
 	
-	/** This method will add a module to the module list, without enabling it
+	/** This method will add a module to the module list, without enabling it.</br>
+	 * This method is deprecated, use addDynamicModule(String name) instead. When using this method, dynamic reloading of the module will not be supported.
 	 * 
 	 * @param clazz The class of the module to be added. */
 	@Debugable
+	@Deprecated
 	public static final void addModule(Class<? extends Module> clazz)
 	{
 		Debugger.notifyMethod(clazz);
@@ -60,6 +81,20 @@ public final class ModuleLoader implements CoreModule
 		}
 	}
 	
+	@Debugable
+	private static final void addLoadedModule(Module m)
+	{
+		Debugger.notifyMethod(m);
+		if (modules.containsKey(m))
+			if (modules.get(m))
+			{
+				Utils.error(
+						"Module m was already loaded and enabled. Disable the module before attempting to reload it.");
+				return;
+			}
+		modules.put(m, false);
+	}
+	
 	/** Call this to enable all not-yet enabled modules that are known to the loader. */
 	@Debugable
 	public static final void enableModules()
@@ -69,23 +104,7 @@ public final class ModuleLoader implements CoreModule
 		{
 			if (modules.get(module))
 				continue;
-			try
-			{
-				if (module.onEnable())
-				{
-					if (VersionHelper.isCompatible(VersionHelper.create(2, 0, 0, -1), module.getClass()))
-						CommandManager.registerCommand(module.getCommandString(), module, Main.plugin);
-					modules.put(module, true);
-					Utils.info("Loaded module " + module.getClass().getName());
-				}
-				else
-					Utils.error("Failed to load module " + module.getClass().getName());
-			}
-			catch (Exception e)
-			{
-				Utils.error("Failed to load module " + module.getClass().getName());
-				e.printStackTrace();
-			}
+			enableLoadedModule(module);
 		}
 		Utils.info("Modules enabled, running post initialization.");
 		for (Module module : modules.keySet())
@@ -111,11 +130,13 @@ public final class ModuleLoader implements CoreModule
 		}
 	}
 	
-	/** This method enables a specific module. If no module with that name is known to the loader yet it will be added to the list.
+	/** This method enables a specific module. If no module with that name is known to the loader yet it will be added to the list.</br>
+	 * This method is deprecated, use enableDynamicModule instead. When using this method, dynamic reloading of the module will not be supported.
 	 * 
 	 * @param clazz The class of the module to be enabled.
 	 * @return true, when the module was successfully enabled. */
 	@Debugable
+	@Deprecated
 	public static final boolean enableModule(Class<? extends Module> clazz)
 	{
 		Debugger.notifyMethod(clazz);
@@ -123,6 +144,11 @@ public final class ModuleLoader implements CoreModule
 		{
 			if (module.getClass().equals(clazz))
 			{
+				if (modules.get(module))
+				{
+					Utils.info("Module was already enabled! Ignoring module.!");
+					return true;
+				}
 				if (module.onEnable())
 				{
 					if (module.getClass().isAnnotationPresent(AutoRegisterListener.class)
@@ -130,13 +156,13 @@ public final class ModuleLoader implements CoreModule
 					{
 						Bukkit.getPluginManager().registerEvents((Listener) module, Main.plugin);
 					}
-					Utils.info("Loaded module " + module.getClass().getName());
+					Utils.info("Enabled module " + module.getClass().getName());
 					modules.put(module, true);
 					return true;
 				}
 				else
 				{
-					Utils.error("Failed to load module " + module.getClass().getName());
+					Utils.error("Failed to enable module " + module.getClass().getName());
 					return false;
 				}
 			}
@@ -151,12 +177,12 @@ public final class ModuleLoader implements CoreModule
 				{
 					Bukkit.getPluginManager().registerEvents((Listener) m, Main.plugin);
 				}
-				Utils.info("Loaded module " + m.getClass().getName());
+				Utils.info("Loaded and enabled module " + m.getClass().getName());
 				return true;
 			}
 			else
 			{
-				Utils.error("Failed to load module " + m.getClass().getName());
+				Utils.error("Failed to enable module " + m.getClass().getName());
 				return false;
 			}
 		}
@@ -167,6 +193,32 @@ public final class ModuleLoader implements CoreModule
 		}
 	}
 	
+	@SuppressWarnings("deprecation")
+	private static final void enableLoadedModule(Module module)
+	{
+		try
+		{
+			if (module.onEnable())
+			{
+				if (VersionHelper.isCompatible(VersionHelper.create(2, 0, 0, -1), module.getClass()))
+					CommandManager.registerCommand(module.getCommandString(), module, Main.plugin);
+				modules.put(module, true);
+				if (VersionHelper.isCompatible(VersionHelper.create(3, 0, 0, 3), module.getClass()))
+				{
+					module.postEnable();
+				}
+				Utils.info("Loaded module " + module.getClass().getName());
+			}
+			else
+				Utils.error("Failed to load module " + module.getClass().getName());
+		}
+		catch (Exception e)
+		{
+			Utils.error("Failed to load module " + module.getClass().getName());
+			e.printStackTrace();
+		}
+	}
+	
 	/** This method lists all modules to the specified CommandSender. The modules will be color coded correspondingly to their enabled status.
 	 * 
 	 * @param sender The person to send the info to, usually the issuer of the command or the console sender.
@@ -194,19 +246,141 @@ public final class ModuleLoader implements CoreModule
 	{
 		for (Module module : modules.keySet())
 		{
-			if (modules.get(module))
+			disableModule(module);
+		}
+	}
+	
+	public static void disableModule(Module module)
+	{
+		if (modules.get(module))
+		{
+			module.onDisable();
+			if (module.getClass().isAnnotationPresent(AutoRegisterListener.class) && (module instanceof Listener))
 			{
-				module.onDisable();
-				if (module.getClass().isAnnotationPresent(AutoRegisterListener.class) && (module instanceof Listener))
+				HandlerList.unregisterAll((Listener) module);
+			}
+		}
+	}
+	
+	@Command(hook = "load")
+	public boolean loadModule(CommandSender sender, String name)
+	{
+		addDynamicModule(name);
+		return true;
+	}
+	
+	public static final void addDynamicModule(String name)
+	{
+		Object[] status = getServerStatus();
+		for (Module m : modules.keySet())
+		{
+			if (m.getClass().getName().equals(name))
+			{
+				Utils.info(
+						"Found existing module, attempting override. WARNING! This operation will halt the main thread until it is completed.");
+				Utils.info("Current server status:");
+				Utils.info("Current system time: " + status[0]);
+				Utils.info("Current tick: " + status[1]);
+				Utils.info("Last TPS: " + status[2]);
+				Utils.info("Entity count: " + status[3]);
+				Utils.info("Player count: " + status[4]);
+				Utils.info("Attempting to load new class definition before disabling and removing the old module:");
+				boolean differs = false;
+				Utils.info("Old class definition: Class@" + m.getClass().hashCode());
+				ClassLoader delegateParent = Module.class.getClassLoader();
+				Class<?> newClass = null;
+				try (URLClassLoader cl = new URLClassLoader(urls, delegateParent))
+				{
+					newClass = cl.loadClass(m.getClass().getName());
+					Utils.info("Found new class definition: Class@" + newClass.hashCode());
+					differs = m.getClass() != newClass;
+				}
+				catch (IOException | ClassNotFoundException e)
+				{
+					Utils.error("Could not find a class definition, aborting now!");
+					e.printStackTrace();
+					return;
+				}
+				if (!differs)
+				{
+					Utils.warn("New class definition equals old definition, are you sure you did everything right?");
+					Utils.info("Aborting now...");
+					return;
+				}
+				Utils.info("Found new class definition, attempting to instantiate:");
+				Module module = null;
+				try
 				{
-					HandlerList.unregisterAll((Listener) module);
+					module = (Module) newClass.newInstance();
 				}
+				catch (InstantiationException | IllegalAccessException e)
+				{
+					Utils.error("Could not instantiate the module, aborting!");
+					e.printStackTrace();
+					return;
+				}
+				Utils.info("Instantiated new class definition, checking versions:");
+				Version oldVersion = m.getClass().getAnnotation(Version.class);
+				Utils.info("Current version: " + VersionHelper.getString(oldVersion));
+				Version newVersion = module.getClass().getAnnotation(Version.class);
+				Utils.info("Version of remote class: " + VersionHelper.getString(newVersion));
+				if (oldVersion.equals(newVersion))
+				{
+					Utils.error("Detected equal module versions, aborting now...");
+					return;
+				}
+				Utils.info("Versions differ, disabling old module:");
+				disableModule(m);
+				Utils.info("Disabled module, overriding the implementation:");
+				modules.remove(m);
+				modules.put(module, false);
+				Utils.info("Successfully updated class definition. Enabling new implementation:");
+				enableLoadedModule(module);
+				Object[] newStatus = getServerStatus();
+				Utils.info("Task complete! Took " + ((long) newStatus[0] - (long) status[0]) + "ms to finish!");
+				Utils.info("Current server status:");
+				Utils.info("Current system time: " + newStatus[0]);
+				Utils.info("Current tick: " + newStatus[1]);
+				Utils.info("Last TPS: " + newStatus[2]);
+				Utils.info("Entity count: " + newStatus[3]);
+				Utils.info("Player count: " + newStatus[4]);
+				return;
 			}
 		}
+		try
+		{
+			Class<?> clazz = mainLoader.loadClass(name);
+			Module module = (Module) clazz.newInstance();
+			addLoadedModule(module);
+			enableLoadedModule(module);
+		}
+		catch (ClassNotFoundException | InstantiationException | IllegalAccessException e)
+		{
+			if (!name.startsWith("com.redstoner.modules."))
+			{
+				Utils.warn(
+						"Couldn't find class definition, suspecting missing path. Autocompleting path, trying again.");
+				addDynamicModule("com.redstoner.modules." + name);
+			}
+			else
+				e.printStackTrace();
+		}
 	}
 	
-	public static boolean loadModule(File f)
+	@SuppressWarnings("deprecation")
+	private static final Object[] getServerStatus()
 	{
-		return false;
+		final Object[] status = new Object[5];
+		status[0] = System.currentTimeMillis();
+		status[1] = MinecraftServer.currentTick;
+		status[2] = MinecraftServer.getServer().recentTps[0];
+		int i = 0;
+		for (World w : Bukkit.getWorlds())
+		{
+			i += w.getEntities().size();
+		}
+		status[3] = i;
+		status[4] = Bukkit.getOnlinePlayers().size();
+		return status;
 	}
 }
diff --git a/src/com/redstoner/misc/VersionHelper.java b/src/com/redstoner/misc/VersionHelper.java
index 9e7bf35..2c4a266 100644
--- a/src/com/redstoner/misc/VersionHelper.java
+++ b/src/com/redstoner/misc/VersionHelper.java
@@ -8,7 +8,7 @@ import com.redstoner.exceptions.MissingVersionException;
 /** This class can be used to compare modules against the loader version or against each other to prevent dependency issues.
  * 
  * @author Pepich */
-@Version(major = 2, minor = 1, revision = 1, compatible = 0)
+@Version(major = 2, minor = 1, revision = 2, compatible = 0)
 public final class VersionHelper
 {
 	private VersionHelper()
@@ -86,6 +86,15 @@ public final class VersionHelper
 		if (!clazz.isAnnotationPresent(Version.class))
 			throw new MissingVersionException("The given class is not associated with a version.");
 		Version ver = clazz.getAnnotation(Version.class);
+		return getString(ver);
+	}
+	
+	/** Returns the String representation of a version.
+	 * 
+	 * @param ver The version to be represented.
+	 * @return The String representation. */
+	public static String getString(Version ver)
+	{
 		return ver.major() + "." + ver.minor() + "." + ver.revision() + "." + ver.compatible();
 	}