请各位帮忙看看，谢谢
Dual.java
package bean;
import java.io.Serializable;
public class Dual implements Serializable {
private Long id;
public Long getId() {
return this.id;
}
public void setId(Long id) {
this.id = id;
}
}
Dual.hbm.xml
<?xml version= "1.0 " encoding= "UTF-8 "?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN "
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd ">
<hibernate-mapping>
<class name= "bean.Dual " table= "DUAL ">
<id name= "id " type= "java.lang.Long " column= "ID ">
<generator class= "sequence "> <!--可以替换-->
<param name= "sequence "> seq_flow </param>
</generator>
</id>
</class>
</hibernate-mapping>
执行select seq_flow.nextval from Dual 这条语句时报错，次句在sqlplus正常执行
错误信息如下：
org.hibernate.hql.ast.QuerySyntaxError: Invalid path: 'seq_flow.nextval ' [select seq_flow.nextval from bean.Dual]
at org.hibernate.hql.ast.ErrorCounter.throwQueryException(ErrorCounter.java:63)
at org.hibernate.hql.ast.QueryTranslatorImpl.analyze(QueryTranslatorImpl.java:196)
at org.hibernate.hql.ast.QueryTranslatorImpl.doCompile(QueryTranslatorImpl.java:130)
at org.hibernate.hql.ast.QueryTranslatorImpl.compile(QueryTranslatorImpl.java:83)
at org.hibernate.impl.SessionFactoryImpl.getQuery(SessionFactoryImpl.java:427)
at org.hibernate.impl.SessionImpl.getQueries(SessionImpl.java:884)
at org.hibernate.impl.SessionImpl.list(SessionImpl.java:834)
at org.hibernate.impl.QueryImpl.list(QueryImpl.java:74)
at DAO.LogicDAO.getSeq(LogicDAO.java:106)
at logic.impl.Logic.getSeq(Logic.java:46)
at web.LogicAction.gotoApplyQues(LogicAction.java:77)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:585)
at org.apache.struts.actions.DispatchAction.dispatchMethod(DispatchAction.java:274)
at org.apache.struts.actions.DispatchAction.execute(DispatchAction.java:194)
at org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:419)
at org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:224)
at org.apache.struts.action.ActionServlet.process(ActionServlet.java:1194)
at org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:414)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:689)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:237)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:157)
at base.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:63)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:186)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:157)