求高手帮忙解决:关于Hibernate！！！！！！！！（历来都是当天结贴）

HTTP Status 500 -

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哪个高手能帮小弟解决啊,感谢不尽!小弟刚开始学,不太懂,这个问题困扰了我快两天了,还没解决....



type Exception report

message

description The server encountered an internal error () that prevented it from fulfilling this request.

exception

org.apache.jasper.JasperException: org.hibernate.hql.ast.QuerySyntaxException: Department is not mapped. [from Department]
org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:532)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:426)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:320)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:266)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
com.jspdev.ch18.EncodingFilter.doFilter(EncodingFilter.java:29)


root cause

org.hibernate.hql.ast.QuerySyntaxException: Department is not mapped. [from Department]
org.hibernate.hql.ast.util.SessionFactoryHelper.requireClassPersister(SessionFactoryHelper.java:157)
org.hibernate.hql.ast.tree.FromElementFactory.addFromElement(FromElementFactory.java:87)
org.hibernate.hql.ast.tree.FromClause.addFromElement(FromClause.java:70)
org.hibernate.hql.ast.HqlSqlWalker.createFromElement(HqlSqlWalker.java:265)
org.hibernate.hql.antlr.HqlSqlBaseWalker.fromElement(HqlSqlBaseWalker.java:3049)
org.hibernate.hql.antlr.HqlSqlBaseWalker.fromElementList(HqlSqlBaseWalker.java:2938)
org.hibernate.hql.antlr.HqlSqlBaseWalker.fromClause(HqlSqlBaseWalker.java:688)
org.hibernate.hql.antlr.HqlSqlBaseWalker.query(HqlSqlBaseWalker.java:544)
org.hibernate.hql.antlr.HqlSqlBaseWalker.selectStatement(HqlSqlBaseWalker.java:281)
org.hibernate.hql.antlr.HqlSqlBaseWalker.statement(HqlSqlBaseWalker.java:229)
org.hibernate.hql.ast.QueryTranslatorImpl.analyze(QueryTranslatorImpl.java:218)
org.hibernate.hql.ast.QueryTranslatorImpl.doCompile(QueryTranslatorImpl.java:158)
org.hibernate.hql.ast.QueryTranslatorImpl.compile(QueryTranslatorImpl.java:109)
org.hibernate.engine.query.HQLQueryPlan.<init>(HQLQueryPlan.java:75)
org.hibernate.engine.query.HQLQueryPlan.<init>(HQLQueryPlan.java:54)
org.hibernate.engine.query.QueryPlanCache.getHQLQueryPlan(QueryPlanCache.java:71)
org.hibernate.impl.AbstractSessionImpl.getHQLQueryPlan(AbstractSessionImpl.java:133)
org.hibernate.impl.AbstractSessionImpl.createQuery(AbstractSessionImpl.java:112)
org.hibernate.impl.SessionImpl.createQuery(SessionImpl.java:1583)
com.jspdev.ch18.Department.getDepartments(Department.java:57)
org.apache.jsp.createEmployee_jsp._jspService(createEmployee_jsp.java:100)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:384)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:320)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:266)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
com.jspdev.ch18.EncodingFilter.doFilter(EncodingFilter.java:29)


root cause

Department is not mapped.
org.hibernate.hql.ast.util.SessionFactoryHelper.requireClassPersister(SessionFactoryHelper.java:157)
org.hibernate.hql.ast.tree.FromElementFactory.addFromElement(FromElementFactory.java:87)
org.hibernate.hql.ast.tree.FromClause.addFromElement(FromClause.java:70)
org.hibernate.hql.ast.HqlSqlWalker.createFromElement(HqlSqlWalker.java:265)
org.hibernate.hql.antlr.HqlSqlBaseWalker.fromElement(HqlSqlBaseWalker.java:3049)
org.hibernate.hql.antlr.HqlSqlBaseWalker.fromElementList(HqlSqlBaseWalker.java:2938)
org.hibernate.hql.antlr.HqlSqlBaseWalker.fromClause(HqlSqlBaseWalker.java:688)
org.hibernate.hql.antlr.HqlSqlBaseWalker.query(HqlSqlBaseWalker.java:544)
org.hibernate.hql.antlr.HqlSqlBaseWalker.selectStatement(HqlSqlBaseWalker.java:281)
org.hibernate.hql.antlr.HqlSqlBaseWalker.statement(HqlSqlBaseWalker.java:229)
org.hibernate.hql.ast.QueryTranslatorImpl.analyze(QueryTranslatorImpl.java:218)
org.hibernate.hql.ast.QueryTranslatorImpl.doCompile(QueryTranslatorImpl.java:158)
org.hibernate.hql.ast.QueryTranslatorImpl.compile(QueryTranslatorImpl.java:109)
org.hibernate.engine.query.HQLQueryPlan.<init>(HQLQueryPlan.java:75)
org.hibernate.engine.query.HQLQueryPlan.<init>(HQLQueryPlan.java:54)
org.hibernate.engine.query.QueryPlanCache.getHQLQueryPlan(QueryPlanCache.java:71)
org.hibernate.impl.AbstractSessionImpl.getHQLQueryPlan(AbstractSessionImpl.java:133)
org.hibernate.impl.AbstractSessionImpl.createQuery(AbstractSessionImpl.java:112)
org.hibernate.impl.SessionImpl.createQuery(SessionImpl.java:1583)
com.jspdev.ch18.Department.getDepartments(Department.java:57)
org.apache.jsp.createEmployee_jsp._jspService(createEmployee_jsp.java:100)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:384)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:320)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:266)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
com.jspdev.ch18.EncodingFilter.doFilter(EncodingFilter.java:29)