Duplicate plugin ID fix.

src/main/java/net/pingex/dcf/modularity/PluginLoader.java

@@ -10,6 +10,7 @@ import java.net.URLClassLoader;
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.nio.file.Paths;
+import java.util.Collections;
 import java.util.HashMap;
 import java.util.Map;
 import java.util.Set;
@@ -101,7 +102,7 @@ public class PluginLoader
 		int counter = 0;
 		for(String item : pluginsToLoad)
 		{
-			LOGGER.debug("Attempting to load {}.", item);
+			LOGGER.debug("Attempting to preload {}.", item);
 
 			Class<?> clazz;
 			try
@@ -117,10 +118,14 @@ public class PluginLoader
 			// Class doesn't implement IPlugin, or doesn't have @Plugin annotation.
 			if(!clazz.isAnnotationPresent(Plugin.class) || !IPlugin.class.isAssignableFrom(clazz))
 			{
-				LOGGER.debug("Class does not implement IPlugin or doesn't gave @Plugin annotation.");
+				LOGGER.debug("Class does not implement IPlugin or doesn't have @Plugin annotation.");
 				continue;
 			}
 
+			if(plugins.containsKey(clazz.getAnnotation(Plugin.class).id()))
+				LOGGER.warn("Found duplicate plugin with id {}. Newly found plugin won't be preloaded.", clazz.getAnnotation(Plugin.class).id());
+			else
+			{
 				try
 				{
 					plugins.put(clazz.getAnnotation(Plugin.class).id(), new PluginWrapper(clazz.asSubclass(IPlugin.class), classLoader));
@@ -132,8 +137,9 @@ public class PluginLoader
 					LOGGER.warn("Plugin " + clazz.getAnnotation(Plugin.class).id() + " failed to preload.", e);
 				}
 			}
+		}
 
-		LOGGER.debug("Loaded up {} plugins from {}.", counter, target.getFileName());
+		LOGGER.debug("Preloaded {} plugins from {}.", counter, target.getFileName());
 		return counter;
 	}
 
@@ -286,4 +292,12 @@ public class PluginLoader
 		LOGGER.info("Unloaded plugin {}.", id);
 		plugin.setState(PluginState.UNLOADED);
 	}
+
+	/**
+	 * Get all plugins and their state.
+	 */
+	public Map<String, PluginWrapper> getPlugins()
+	{
+		return Collections.unmodifiableMap(plugins);
+	}
 }