EJB3.0中查詢boolean值的方法

我定義了一個類：HibernateBooleanDemo

只有兩個屬性：id和enabled，分別是String和boolean類型，分別對應表中的id和isEnabled列。並編寫了相應的get和set方法和DAO類。但是如下代碼很奇怪：

String hql = \"from HibernateBooleanDemo where isEnabled=false\";

Session s = HibernateSessionFactory.getSession();

Transaction t = s.beginTransaction();

Query q = s.createQuery(hql);

List list = q.list();

System.out.println(list.size());

System.out.println(((HibernateBooleanDemo)list.get(0)).isEnabled());

t.commit();

HibernateSessionFactory.closeSession();

在上面的查詢語句中寫列名即isEnabled時可以正常運行。但是寫屬性enabled時，卻拋出異常，大概意思是說不能解析該屬性。

一直不明白是什麼原因。請大家指點

【AmethystWish】:

若\"from HibernateBooleanDemo where isEnabled=false\";寫為\"from HibernateBooleanDemo where enabled=false\";錯誤如下：

aused by: com.mysql.jdbc.exceptions.MySQLSyntaxErrorException: Unknown column \'enabled\' in \'where clause\'

at com.MySQL.jdbc.SQLError.createSQLException(SQLError.Java:936)

at com.mysql.jdbc.MysqlIO.checkErrorPacket(MySQLIO.Java:2870)

at com.mysql.jdbc.MysqlIO.sendCommand(MySQLIO.Java:1573)

at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MySQLIO.Java:1665)

at com.MySQL.jdbc.Connection.execSQL(Connection.Java:3124)

at com.MySQL.jdbc.PreparedStatement.executeInternal(PreparedStatement.Java:1149)

at com.MySQL.jdbc.PreparedStatement.executeQuery(PreparedStatement.Java:1262)

at org.hibernate.jdbc.AbstractBatcher.getResultSet(AbstractBatcher.Java:139)

at org.hibernate.loader.Loader.getResultSet(Loader.Java:1669)

at org.hibernate.loader.Loader.doQuery(Loader.Java:662)

at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.Java:224)

at org.hibernate.loader.Loader.doList(Loader.Java:2145)

... 8 more

【liandti】:

from HibernateBooleanDemo h where h.enabled=false

如果用屬性就加別名

【AmethystWish】:

查詢字符串改為：\"from HibernateBooleanDemo h where h.enabled=false\";之後運行，結果如下：

Exception in thread \"main\" org.hibernate.QueryException: could not resolve property: enabled of: org.acman.demo.HibernateBooleanDemo [from org.acman.demo.HibernateBooleanDemo h where h.enabled=false]

at org.hibernate.persister.entity.AbstractPropertyMapping.throwPropertyException(AbstractPropertyMapping.Java:43)[Page]

at org.hibernate.persister.entity.AbstractPropertyMapping.toType(AbstractPropertyMapping.Java:37)

at org.hibernate.persister.entity.AbstractEntityPersister.toType(AbstractEntityPersister.Java:1265)

at org.hibernate.hql.ast.tree.FromElementType.getPropertyType(FromElementType.Java:279)

at org.hibernate.hql.ast.tree.FromElement.getPropertyType(FromElement.Java:372)

at org.hibernate.hql.ast.tree.DotNode.getDataType(DotNode.Java:539)

at org.hibernate.hql.ast.tree.DotNode.prepareLhs(DotNode.Java:221)

at org.hibernate.hql.ast.tree.DotNode.resolve(DotNode.Java:172)

at org.hibernate.hql.ast.tree.FromReferenceNode.resolve(FromReferenceNode.Java:94)

at org.hibernate.hql.ast.tree.FromReferenceNode.resolve(FromReferenceNode.Java:90)

at org.hibernate.hql.ast.HqlSqlWalker.resolve(HqlSqlWalker.Java:725)

at org.hibernate.hql.antlr.HqlSqlBaseWalker.expr(HqlSqlBaseWalker.Java:1215)

at org.hibernate.hql.antlr.HqlSqlBaseWalker.exprOrSubquery(HqlSqlBaseWalker.Java:4032)

at org.hibernate.hql.antlr.HqlSqlBaseWalker.comparisonExpr(HqlSqlBaseWalker.Java:3518)

at org.hibernate.hql.antlr.HqlSqlBaseWalker.logicalExpr(HqlSqlBaseWalker.Java:1758)

at org.hibernate.hql.antlr.HqlSqlBaseWalker.whereClause(HqlSqlBaseWalker.Java:776)

at org.hibernate.hql.antlr.HqlSqlBaseWalker.query(HqlSqlBaseWalker.Java:577)

at org.hibernate.hql.antlr.HqlSqlBaseWalker.selectStatement(HqlSqlBaseWalker.Java:281)

【AmethystWish】:

如果屬性是其它類型的，如字符串類型的，運行就沒有問題，如果是bool、boolean類型的就這樣，不知道為什麼。初學hibernante，應該有不知道的地方

【AmethystWish】:

已解決。錯誤總結：類映射文件中

元素的name屬性對應類中屬性的名字,要以小寫字母開頭。我使用HibernateSynchronizer工具自動生成類映射文件，name屬性全部以大寫字母開頭。

但是很奇怪，其它類型的屬性沒有問題，只有布爾類型的有問題。