NullPointerException怎样解决
org.hibernate.InvalidMappingException: Could not parse mapping document from resource com/chinasei/hibernate/model/SchoolMaster.hbm.xmlat org.hibernate.cfg.Configuration.addResource(Configuration.java:616)
at org.hibernate.cfg.Configuration.parseMappingElement(Configuration.java:1635)
at org.hibernate.cfg.Configuration.parseSessionFactory(Configuration.java:1603)
at org.hibernate.cfg.Configuration.doConfigure(Configuration.java:1582)
at org.hibernate.cfg.Configuration.doConfigure(Configuration.java:1556)
at org.hibernate.cfg.Configuration.configure(Configuration.java:1476)
at com.chinasei.hibernate.HibernateSessionFactory.rebuildSessionFactory(HibernateSessionFactory.java:69)
at com.chinasei.hibernate.HibernateSessionFactory.getSession(HibernateSessionFactory.java:53)
at com.chinasei.hibernate.dao.BaseHibernateDAO.getSession(BaseHibernateDAO.java:14)
at com.chinasei.hibernate.dao.SchoolMasterDAO.save(SchoolMasterDAO.java:17)
at org.apache.jsp.School_jsp._jspService(School_jsp.java:75)
at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:377)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:313)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:260)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:298)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:852)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:588)
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)
at java.lang.Thread.run(Unknown Source)
Caused by: org.hibernate.DuplicateMappingException: Duplicate class/entity mapping com.chinasei.hibernate.model.School
at org.hibernate.cfg.Mappings.addClass(Mappings.java:141)
at org.hibernate.cfg.HbmBinder.bindRoot(HbmBinder.java:167)
at org.hibernate.cfg.Configuration.add(Configuration.java:716)
at org.hibernate.cfg.Configuration.addInputStream(Configuration.java:551)
at org.hibernate.cfg.Configuration.addResource(Configuration.java:613)
... 28 more
汪昱仁
java.lang.NullPointerException
at com.chinasei.hibernate.dao.SchoolMasterDAO.save(SchoolMasterDAO.java:20)
at org.apache.jsp.School_jsp._jspService(School_jsp.java:75)
at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:377)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:313)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:260)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:298)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:852)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:588)
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)
at java.lang.Thread.run(Unknown Source)
2013-12-4 16:41:43 org.apache.catalina.core.StandardWrapperValve invoke
严重: Servlet.service() for servlet jsp threw exception
java.lang.NullPointerException
at com.chinasei.hibernate.dao.SchoolMasterDAO.save(SchoolMasterDAO.java:33)
at org.apache.jsp.School_jsp._jspService(School_jsp.java:75)
at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:377)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:313)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:260)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:298)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:852)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:588)
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)
at java.lang.Thread.run(Unknown Source)
<?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">
<!--
Mapping file autogenerated by MyEclipse Persistence Tools
-->
<hibernate-mapping>
<class name="com.chinasei.hibernate.model.School" table="SCHOOL" schema="dbo" catalog="chinasei">
<id name="schoolID" type="int">
<column name="SCHOOL_ID" precision="8" scale="0"/>
</id>
<property name="schoolName" type="string">
<column name="SCHOOL_NAME" length="50" not-null="true"/>
</property>
<property name="schoolAddress" type="string">
<column name="SCHOOL_ADDRESS" length="100" not-null="true"/>
</property>
<one-to-one name="schoolMaster" class="com.chinasei.hibernate.model.SchoolMaster" cascade="all"/>
</class>
<class name="com.chinasei.hibernate.model.SchoolMaster" table="SchoolMaster" schema="dbo" catalog="chinasei">
<id name="schoolID" type="int">
<column name="SCHOOL_ID" precision="8" scale="0"/>
<generator class="foreign">
<param name="property">school</param>
</generator>
</id>
<property name="masterName" type="string">
<column name="MASTER_NAME" length="50" not-null="true"/>
</property>
<one-to-one name="school" class="com.chinasei.hibernate.model.School" constrained="true" cascade="none"/>
</class>
</hibernate-mapping>
package com.chinasei.hibernate.dao;
import java.util.List;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.hibernate.Session;
import org.hibernate.Transaction;
import org.hibernate.criterion.Example;
import com.chinasei.hibernate.model.SchoolMaster;
public class SchoolMasterDAO extends BaseHibernateDAO{
private static final Log log = LogFactory.getLog(SchoolMasterDAO.class);
public void save(SchoolMaster transientInstance) {
log.debug("saving Students instance");
Session session = getSession();
Transaction tx = null;
try{
tx = session.beginTransaction();
session.save(transientInstance);
tx.commit();
log.debug("save successful");
}catch(RuntimeException re){
log.error("save failed",re);
if(tx!=null){
tx.rollback();
}
re.printStackTrace();
throw re;
}finally{
session.close();
}
}
public List findByExample(SchoolMaster instance) {
log.debug("finding Course instance by example");
try {
List results = getSession().createCriteria(
"com.chinasei.hibernate.dao.Course").add(
Example.create(instance)).list();
log.debug("find by example successful, result size: "
+ results.size());
return results;
} catch (RuntimeException re) {
log.error("find by example failed", re);
throw re;
}
}
}
--------------------编程问答-------------------- 应该是bean文件盒xml文件没有map上吧 --------------------编程问答-------------------- 写追踪语句追踪需要输出的内容 --------------------编程问答--------------------
<?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">
<!--
Mapping file autogenerated by MyEclipse Persistence Tools
-->
<hibernate-mapping>
<class name="com.chinasei.hibernate.model.School" table="SCHOOL" schema="dbo" catalog="chinasei">
<id name="schoolID" type="int">
<column name="SCHOOL_ID" precision="8" scale="0"/>
</id>
<property name="schoolName" type="string">
<column name="SCHOOL_NAME" length="50" not-null="true"/>
</property>
<property name="schoolAddress" type="string">
<column name="SCHOOL_ADDRESS" length="100" not-null="true"/>
</property>
<one-to-one name="schoolMaster" class="com.chinasei.hibernate.model.SchoolMaster" cascade="all"/>
</class>
<class name="com.chinasei.hibernate.model.SchoolMaster" table="SchoolMaster" schema="dbo" catalog="chinasei">
<id name="schoolID" type="int">
<column name="SCHOOL_ID" precision="8" scale="0"/>
<generator class="foreign">
<param name="property">school</param>
</generator>
</id>
<property name="masterName" type="string">
<column name="MASTER_NAME" length="50" not-null="true"/>
</property>
<one-to-one name="school" class="com.chinasei.hibernate.model.School" constrained="true" cascade="none"/>
</class>
</hibernate-mapping>
package com.chinasei.hibernate.dao;
import java.util.List;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.hibernate.Session;
import org.hibernate.Transaction;
import org.hibernate.criterion.Example;
import com.chinasei.hibernate.model.SchoolMaster;
public class SchoolMasterDAO extends BaseHibernateDAO{
private static final Log log = LogFactory.getLog(SchoolMasterDAO.class);
public void save(SchoolMaster transientInstance) {
log.debug("saving Students instance");
Session session = getSession();
Transaction tx = null;
try{
tx = session.beginTransaction();
session.save(transientInstance);
tx.commit();
log.debug("save successful");
}catch(RuntimeException re){
log.error("save failed",re);
if(tx!=null){
tx.rollback();
}
re.printStackTrace();
throw re;
}finally{
session.close();
}
}
public List findByExample(SchoolMaster instance) {
log.debug("finding Course instance by example");
try {
List results = getSession().createCriteria(
"com.chinasei.hibernate.dao.Course").add(
Example.create(instance)).list();
log.debug("find by example successful, result size: "
+ results.size());
return results;
} catch (RuntimeException re) {
log.error("find by example failed", re);
throw re;
}
}
} 先帮你整理好代码
--------------------编程问答--------------------
像这种没有格式化的帖子，就算懂也不回帖。。
补充：Java , Eclipse
