@Override
	public int hashCode() {
		final int prime = 31;
		int result = 1;
		result = prime * result + ((this.content == null) ? 0 : this.content.hashCode());
		result = prime * result + ((this.mime == null) ? 0 : this.mime.hashCode());
		result = prime * result + ((this.reference == null) ? 0 : this.reference.hashCode());
		result = prime * result + ((this.url == null) ? 0 : this.url.hashCode());
		return result;
	}