Talk:Jakarta Persistence Query Language

Mistake in example?

This article currently has the following example:

import javax.persistence.EntityManager;
import javax.persistence.Query;
import org.apache.commons.lang.StringUtils;

...

@SuppressWarnings("unchecked")
public List<Author> getAuthorsByLastName(String lastName) {
    String queryString = "SELECT a FROM Author a " +
                         "WHERE :lastName IS NULL OR LOWER(a.lastName) = :lastName";
    Query query = getEntityManager().createQuery(queryString);
    
    query.setParameter("lastName", StringUtils.lowerCase(lastName));
    return query.getResultList();
}

(Keep in mind the Author class has a field private String firstName.)

The WHERE :lastName IS NULL part doesn't make sense to me. Shouldn't it be written WHERE lastName IS NULL (i.e., without the colon)? In case I'm wrong, can someone please explain the semantics of this query? --Abdull (talk) 15:20, 29 September 2012 (UTC)

What is Author in the first query string?

Anyone just reading this page will be immediately close the page because it's not at all clear what is Author in the first query? I guess it's a class which has been shown before, so making a link to the source code makes reading this article much less annoying, maybe even pleasant... 92.195.55.224 (talk) 18:47, 1 December 2012 (UTC)

Seems like it's because of a vandalism by the following entries: (cur | prev) 09:39, 9 October 2012‎ 183.82.123.104 (talk)‎ . . (3,549 bytes) (-220)‎ . . (→‎Examples) (undo) (cur | prev) 09:38, 9 October 2012‎ 183.82.123.104 (talk)‎ . . (3,769 bytes) (-300)‎ . . (→‎Examples) (undo)

Someone with more knowledge please fix it. 174.61.157.234 (talk) 07:20, 12 December 2012 (UTC)