public static String extractDoi(Article article) {
		try {
			List<ArticleId> ids = article.getFront().getArticleMeta()
					.getArticleId();
			for (ArticleId id : ids) {
				if ("doi".equals(id.getPubIdType())) {
					return id.getContent();
				}
			}
		} catch (Exception e) {
			System.err.println(e);
		}
		return null;
	}
public static String extractDoi ( Article article ) { try { List < ArticleId > ids = article . getFront ( ) . getArticleMeta ( ) . getArticleId ( ) ; for ( ArticleId id : ids ) { if ( "doi" . equals ( id . getPubIdType ( ) ) ) { return id . getContent ( ) ; } } } catch ( Exception e ) { System . err . println ( e ) ; } return null ; }
@param article
@return the doi string of this article, or null