Program: 134186
Project: 134186
Buggy source:
public final List<T> load(Class<? extends AbilityLoadable> classType){
  for (  File file : files) {
    try {
      final JarFile jarFile=new JarFile(file);
      String mainClass=null;
      if (jarFile.getEntry("String_Node_Str") != null) {
        JarEntry element=jarFile.getJarEntry("String_Node_Str");
        BufferedReader reader=new BufferedReader(new InputStreamReader(jarFile.getInputStream(element)));
        mainClass=reader.readLine().substring(12);
      }
      if (mainClass != null) {
        Class<?> clazz=Class.forName(mainClass,true,loader);
        if (clazz != null) {
          Class<? extends AbilityLoadable> loadableClass=clazz.asSubclass(classType);
          Constructor<? extends AbilityLoadable> ctor=loadableClass.getConstructor(ctorParams);
          T loadable=(T)ctor.newInstance(paramTypes);
          LoadResult result=loadable.init();
          if (result.getResult().equals(Result.SUCCESS)) {
            loadables.add(loadable);
            AbilityLoadEvent<T> event=new AbilityLoadEvent<T>(plugin,loadable,jarFile);
            plugin.getServer().getPluginManager().callEvent(event);
            continue;
          }
          String reason=result.getReason();
          if (reason != null && !reason.isEmpty()) {
            getLogger().log(Level.INFO,"String_Node_Str" + file.getName() + "String_Node_Str"+ reason);
          }
        }
 else {
          jarFile.close();
          throw new ClassNotFoundException();
        }
      }
 else {
        jarFile.close();
        throw new ClassNotFoundException();
      }
    }
 catch (    ClassCastException e) {
      e.printStackTrace();
      getLogger().log(Level.WARNING,"String_Node_Str" + file.getPath() + "String_Node_Str");
      getLogger().log(Level.WARNING,"String_Node_Str" + file.getName() + "String_Node_Str");
    }
catch (    ClassNotFoundException e) {
      e.printStackTrace();
      getLogger().log(Level.WARNING,"String_Node_Str");
      getLogger().log(Level.WARNING,"String_Node_Str" + file.getName() + "String_Node_Str");
    }
catch (    Exception e) {
      e.printStackTrace();
      getLogger().log(Level.WARNING,"String_Node_Str");
      getLogger().log(Level.WARNING,"String_Node_Str" + file.getName() + "String_Node_Str");
    }
  }
  return loadables;
}

Fixed version (ground truth):
public final List<T> load(Class<? extends AbilityLoadable> classType){
  for (  File file : files) {
    try (final JarFile jarFile=new JarFile(file)){
      String mainClass=null;
      if (jarFile.getEntry("String_Node_Str") != null) {
        JarEntry element=jarFile.getJarEntry("String_Node_Str");
        BufferedReader reader=new BufferedReader(new InputStreamReader(jarFile.getInputStream(element)));
        mainClass=reader.readLine().substring(12);
      }
      if (mainClass != null) {
        Class<?> clazz=Class.forName(mainClass,true,loader);
        if (clazz != null) {
          Class<? extends AbilityLoadable> loadableClass=clazz.asSubclass(classType);
          Constructor<? extends AbilityLoadable> ctor=loadableClass.getConstructor(ctorParams);
          T loadable=(T)ctor.newInstance(paramTypes);
          LoadResult result=loadable.init();
          if (result.getResult().equals(Result.SUCCESS)) {
            loadables.add(loadable);
            AbilityLoadEvent<T> event=new AbilityLoadEvent<T>(plugin,loadable,jarFile);
            plugin.getServer().getPluginManager().callEvent(event);
            continue;
          }
          String reason=result.getReason();
          if (reason != null && !reason.isEmpty()) {
            getLogger().log(Level.INFO,"String_Node_Str" + file.getName() + "String_Node_Str"+ reason);
          }
        }
 else {
          jarFile.close();
          throw new ClassNotFoundException();
        }
      }
 else {
        jarFile.close();
        throw new ClassNotFoundException();
      }
    }
 catch (    ClassCastException e) {
      e.printStackTrace();
      getLogger().log(Level.WARNING,"String_Node_Str" + file.getPath() + "String_Node_Str");
      getLogger().log(Level.WARNING,"String_Node_Str" + file.getName() + "String_Node_Str");
    }
catch (    ClassNotFoundException e) {
      e.printStackTrace();
      getLogger().log(Level.WARNING,"String_Node_Str");
      getLogger().log(Level.WARNING,"String_Node_Str" + file.getName() + "String_Node_Str");
    }
catch (    Exception e) {
      e.printStackTrace();
      getLogger().log(Level.WARNING,"String_Node_Str");
      getLogger().log(Level.WARNING,"String_Node_Str" + file.getName() + "String_Node_Str");
    }
  }
  return loadables;
}