@Override
    public boolean equals(Object obj) {
        if (obj == null) {
            return false;
        }
        if (getClass() != obj.getClass()) {
            return false;
        }
        final Usuario other = (Usuario) obj;
        if ((this.id == null) ? (other.id != null) : !this.id.equals(other.id)) {
            return false;
        }
        return true;
    }