I am trying to build a game where the character find and follows a new path when a new destination is issued by the player, kinda like how units in RTS games work. This is done on a TMX map and I am using the A Star path finder utilities in Andengine to do this.David helped me on that: How can I change the path a sprite is following in real time? At the moment, every-time a new path is issued, I have to abandon the existing PathModifer and Path instances, and create new ones, and from what I read so far, creating new objects when you could re-use existing ones are a big waste for mobile applications. This is how I coded it at the moment: private void loadPathFound() { if (mAStarPath != null) { modifierPath = new org.andengine.entity.modifier.PathModifier.Path(mAStarPath.getLength()); /* replace the first node in the path as the player's current position */ modifierPath.to(player.convertLocalToSceneCoordinates(12, 31)[Constants.VERTEX_INDEX_X]-12, player.convertLocalToSceneCoordinates(12, 31)[Constants.VERTEX_INDEX_Y]-31); for (int i=1; i<mAStarPath.getLength(); i++) { modifierPath.to(mAStarPath.getX(i)*TILE_WIDTH, mAStarPath.getY(i)*TILE_HEIGHT); /* passing in the duration depended on the length of the path, so that the animation has a constant duration for every step */ player.registerEntityModifier(new PathModifier(modifierPath.getLength()/100, modifierPath, null, mIPathModifierListener)); } } The ideal implementation will be to always have just one object of PathModifer and just reset the destination of the path. But I don't know how you can apply the singleton patther on Andengine's PathModifer, there is no method to reset attribute of the path nor the pathModifer. So without re-write the PathModifer and the Path class, or use reflection, is there any other way to implement singleton PathModifer? Thanks for your help.