Fixed basic dependency functionality - If class can't be found, all other .jar files are scanned

By: Raphfrk <raphfrk@gmail.com>

paper-api/src/main/java/org/bukkit/plugin/java/JavaPluginLoader.java

@@ -39,7 +39,7 @@ public final class JavaPluginLoader implements PluginLoader {
             Pattern.compile("\\.jar$"),
     };
     private final Map<String, Class<?>> classes = new HashMap<String, Class<?>>();
-    private final Map<String, File> files = new HashMap<String, File>();
+    private final Map<String, PluginClassLoader> loaders = new HashMap<String, PluginClassLoader>();
 
     public JavaPluginLoader(Server instance) {
         server = instance;
@@ -81,27 +81,21 @@ public final class JavaPluginLoader implements PluginLoader {
              throw new InvalidPluginException(ex);
         }
 
-        ArrayList<File> dependFiles = new ArrayList<File>();
-
         for(String pluginName : depend) {
-            if(files == null) {
+            if(loaders == null) {
                 throw new UnknownDependencyException(pluginName);
             }
-            File current = files.get(pluginName);
+            PluginClassLoader current = loaders.get(pluginName);
             if(current == null) {
                 throw new UnknownDependencyException(pluginName);
             }
-            dependFiles.add(current);
         }
 
+        PluginClassLoader loader = null;
         try {
-            URL[] urls = new URL[dependFiles.size() + 1];
+            URL[] urls = new URL[1];
             urls[0] = file.toURI().toURL();
-            int cnt = 1;
+            loader = new PluginClassLoader(this, urls, getClass().getClassLoader());
-            for(File f : dependFiles) {
-                urls[cnt++] = f.toURI().toURL();
-            }
-            ClassLoader loader = new PluginClassLoader(this, urls, getClass().getClassLoader());
             Class<?> jarClass = Class.forName(description.getMain(), true, loader);
             Class<? extends JavaPlugin> plugin = jarClass.asSubclass(JavaPlugin.class);
 
@@ -113,7 +107,7 @@ public final class JavaPluginLoader implements PluginLoader {
             throw new InvalidPluginException(ex);
         }
 
-        files.put(description.getName(), file);
+        loaders.put(description.getName(), (PluginClassLoader)loader);
 
         return (Plugin)result;
     }
@@ -143,7 +137,22 @@ public final class JavaPluginLoader implements PluginLoader {
     }
 
     public Class<?> getClassByName(final String name) {
-        return classes.get(name);
+        Class<?> cachedClass = classes.get(name);
+        if(cachedClass != null) {
+            return cachedClass;
+        } else {
+            for(String current : loaders.keySet()) {
+                PluginClassLoader loader = loaders.get(current);
+                try {
+                    cachedClass = loader.findClass(name, false);
+                } catch (ClassNotFoundException cnfe) {
+                }
+                if(cachedClass != null) {
+                    return cachedClass;
+                }
+            }
+        }
+        return null;
     }
 
     public void setClass(final String name, final Class<?> clazz) {
@@ -450,6 +459,11 @@ public final class JavaPluginLoader implements PluginLoader {
         if (!plugin.isEnabled()) {
             JavaPlugin jPlugin = (JavaPlugin)plugin;
 
+            String pluginName = jPlugin.getDescription().getName();
+            if(!loaders.containsKey(pluginName)) {
+                loaders.put(pluginName, (PluginClassLoader)jPlugin.getClassLoader());
+            }
+
             jPlugin.setEnabled(true);
             server.getPluginManager().callEvent(new PluginEvent(Event.Type.PLUGIN_ENABLE, plugin));
         }
@@ -468,7 +482,7 @@ public final class JavaPluginLoader implements PluginLoader {
 
             server.getPluginManager().callEvent(new PluginEvent(Event.Type.PLUGIN_DISABLE, plugin));
 
-            files.remove(jPlugin.getDescription().getName());
+            loaders.remove(jPlugin.getDescription().getName());
 
             if (cloader instanceof PluginClassLoader) {
                 PluginClassLoader loader = (PluginClassLoader)cloader;

paper-api/src/main/java/org/bukkit/plugin/java/PluginClassLoader.java

@@ -21,10 +21,16 @@ public class PluginClassLoader extends URLClassLoader {
 
     @Override
     protected Class<?> findClass(String name) throws ClassNotFoundException {
+        return findClass(name, true);
+    }
+
+    protected Class<?> findClass(String name, boolean checkGlobal) throws ClassNotFoundException {
         Class<?> result = classes.get(name);
 
         if (result == null) {
+            if(checkGlobal) {
                 result = loader.getClassByName(name);
+            }
 
             if (result == null) {
                 result = super.findClass(name);