HQL:查询java.util.Map的值

Question

我尝试了这个hql查询,但是当我在以下查询中使用actProp [:key] =:value时,它会抛出UnsupportedOperationException :

选择映射actionProperties中包含值对x,y或z,y的所有操作:

Query query = getSession().createQuery(
    "select a from Action a                     " +
    " join a.actionProperties actProp           " +
    "   where (index(actProp) = :key            " +
    "           and actProp[:key] = :value )    " +
    "     or  (index(actProp) = :key2           " +
    "           and actProp[:key2] = :value )   ");

例外:

java.lang.UnsupportedOperationException
        at org.hibernate.hql.ast.tree.IdentNode.resolveIndex(IdentNode.java:67)

在实体Action中:

@CollectionOfElements(fetch = FetchType.EAGER)
private Map<String, String> actionProperties;

我也尝试过使用Hibernate Criteria,但我不认为这是可能的.

有没有人知道要替换的东西:actProp [:key] =:带有工作代码的值？

Answer 1

经过一些试验和错误,我终于找到了解决方案,这不是那么简单.

Query query = getSession().createQuery(
        " from Action a " +
        " join a.actionProperties actProp                      " +
        "   where( (index(actProp) = :key                      " +
        "           and :value in elements(a.actionProperties))" +
        "       or (index(actProp) = :key2                     " +
        "           and :value in elements(a.actionProperties)) )"
        );

因此,为了匹配键我使用了index()函数并匹配我使用elements()函数的值.

如果您知道更好的解决方案,请告诉我.