@Override
    public int hashCode() {
        int hash = 5;
        hash = 31 * hash + (super.hashCode());
        hash = 31 * hash + (this.materialList != null ? this.materialList.hashCode() : 0);
        hash = 31 * hash + (this.materialName != null ? this.materialName.hashCode() : 0);
        return hash;
    }
OgreMeshKey is used to load Ogre3D mesh.xml models with a specific
material file or list. This allows customizing from where the materials
are retrieved, instead of loading the material file as the same
name as the model (the default).

@author Kirill Vainer
jme3-plugins/src/ogre/java/com/jme3/scene/plugins/ogre/OgreMeshKey.java