Java 随机出现休眠错误

我在通过hibernate访问db时遇到了4个不同的错误，它们是随机出现的。它们并不总是出现，特别是在调试模式下。请告诉我各种修复方法。错误如下所示

问我是否需要更多的信息

错误1：

org.springframework.web.util.NestedServletException: Request processing failed; 
nested exception is org.hibernate.exception.GenericJDBCException: could not execute query
org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:656)
org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:549)
javax.servlet.http.HttpServlet.service(HttpServlet.java:621)
javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
root cause

org.hibernate.exception.GenericJDBCException: could not execute query

org.hibernate.exception.SQLStateConverter.handledNonSpecificException(SQLStateConverter.java:126)
org.hibernate.exception.SQLStateConverter.convert(SQLStateConverter.java:114)
org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:66)
org.hibernate.loader.Loader.doList(Loader.java:2231)
org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2125)
org.hibernate.loader.Loader.list(Loader.java:2120)
org.hibernate.loader.hql.QueryLoader.list(QueryLoader.java:401)
org.hibernate.hql.ast.QueryTranslatorImpl.list(QueryTranslatorImpl.java:361)
org.hibernate.engine.query.HQLQueryPlan.performList(HQLQueryPlan.java:196)
org.hibernate.impl.SessionImpl.list(SessionImpl.java:1148)
org.hibernate.impl.QueryImpl.list(QueryImpl.java:102)
com.metropro.eps.dao.impl.NewlyAddedDevicesDaoImpl.getSeriesDevices(NewlyAddedDevicesDaoImpl.java:85)
com.metropro.eps.bo.impl.NewlyAddedDevicesBoImpl.getSeriesDevices(NewlyAddedDevicesBoImpl.java:49)
com.metropro.eps.controller.RepositoryController.getSeriesDevices(RepositoryController.java:105)
sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
java.lang.reflect.Method.invoke(Unknown Source)
org.springframework.web.bind.annotation.support.HandlerMethodInvoker.invokeHandlerMethod(HandlerMethodInvoker.java:176)
org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.invokeHandlerMethod(AnnotationMethodHandlerAdapter.java:426)
org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.handle(AnnotationMethodHandlerAdapter.java:414)
org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:790)
org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:719)
org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:644)
org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:549)
javax.servlet.http.HttpServlet.service(HttpServlet.java:621)
javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
root cause

java.sql.SQLException: You can't operate on a closed Statement!!!
com.mchange.v2.sql.SqlUtils.toSQLException(SqlUtils.java:106)
com.mchange.v2.sql.SqlUtils.toSQLException(SqlUtils.java:65)
com.mchange.v2.c3p0.impl.NewProxyPreparedStatement.executeQuery(NewProxyPreparedStatement.java:85)
org.hibernate.jdbc.AbstractBatcher.getResultSet(AbstractBatcher.java:208)
org.hibernate.loader.Loader.getResultSet(Loader.java:1808)
org.hibernate.loader.Loader.doQuery(Loader.java:697)
org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:259)
org.hibernate.loader.Loader.doList(Loader.java:2228)
org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2125)
org.hibernate.loader.Loader.list(Loader.java:2120)
org.hibernate.loader.hql.QueryLoader.list(QueryLoader.java:401)
org.hibernate.hql.ast.QueryTranslatorImpl.list(QueryTranslatorImpl.java:361)
org.hibernate.engine.query.HQLQueryPlan.performList(HQLQueryPlan.java:196)
org.hibernate.impl.SessionImpl.list(SessionImpl.java:1148)
org.hibernate.impl.QueryImpl.list(QueryImpl.java:102)
com.metropro.eps.dao.impl.NewlyAddedDevicesDaoImpl.getSeriesDevices(NewlyAddedDevicesDaoImpl.java:85)
com.metropro.eps.bo.impl.NewlyAddedDevicesBoImpl.getSeriesDevices(NewlyAddedDevicesBoImpl.java:49)
com.metropro.eps.controller.RepositoryController.getSeriesDevices(RepositoryController.java:105)
sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
java.lang.reflect.Method.invoke(Unknown Source)
org.springframework.web.bind.annotation.support.HandlerMethodInvoker.invokeHandlerMethod(HandlerMethodInvoker.java:176)
org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.invokeHandlerMethod(AnnotationMethodHandlerAdapter.java:426)
org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.handle(AnnotationMethodHandlerAdapter.java:414)
org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:790)
org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:719)
org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:644)
org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:549)
javax.servlet.http.HttpServlet.service(HttpServlet.java:621)
javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
root cause

java.lang.NullPointerException
com.mchange.v2.c3p0.impl.NewProxyPreparedStatement.executeQuery(NewProxyPreparedStatement.java:78)
org.hibernate.jdbc.AbstractBatcher.getResultSet(AbstractBatcher.java:208)
org.hibernate.loader.Loader.getResultSet(Loader.java:1808)
org.hibernate.loader.Loader.doQuery(Loader.java:697)
org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:259)
org.hibernate.loader.Loader.doList(Loader.java:2228)
org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2125)
org.hibernate.loader.Loader.list(Loader.java:2120)
org.hibernate.loader.hql.QueryLoader.list(QueryLoader.java:401)
org.hibernate.hql.ast.QueryTranslatorImpl.list(QueryTranslatorImpl.java:361)
org.hibernate.engine.query.HQLQueryPlan.performList(HQLQueryPlan.java:196)
org.hibernate.impl.SessionImpl.list(SessionImpl.java:1148)
org.hibernate.impl.QueryImpl.list(QueryImpl.java:102)
com.metropro.eps.dao.impl.NewlyAddedDevicesDaoImpl.getSeriesDevices(NewlyAddedDevicesDaoImpl.java:85)
com.metropro.eps.bo.impl.NewlyAddedDevicesBoImpl.getSeriesDevices(NewlyAddedDevicesBoImpl.java:49)
com.metropro.eps.controller.RepositoryController.getSeriesDevices(RepositoryController.java:105)
sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
java.lang.reflect.Method.invoke(Unknown Source)
org.springframework.web.bind.annotation.support.HandlerMethodInvoker.invokeHandlerMethod(HandlerMethodInvoker.java:176)
org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.invokeHandlerMethod(AnnotationMethodHandlerAdapter.java:426)
org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.handle(AnnotationMethodHandlerAdapter.java:414)
org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:790)
org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:719)
org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:644)
org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:549)
javax.servlet.http.HttpServlet.service(HttpServlet.java:621)
javax.servlet.http.HttpServlet.service(HttpServlet.java:728)

错误2：

exception

org.springframework.web.util.NestedServletException: Request processing failed; nested exception is java.lang.NullPointerException
org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:656)
org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:549)
javax.servlet.http.HttpServlet.service(HttpServlet.java:621)
javax.servlet.http.HttpServlet.service(HttpServlet.java:728)

root cause

java.lang.NullPointerException
com.mysql.jdbc.ResultSetImpl.getStringInternal(ResultSetImpl.java:5727)
com.mysql.jdbc.ResultSetImpl.getString(ResultSetImpl.java:5577)
com.mysql.jdbc.ResultSetImpl.getString(ResultSetImpl.java:5617)
com.mchange.v2.c3p0.impl.NewProxyResultSet.getString(NewProxyResultSet.java:3342)
org.hibernate.type.StringType.get(StringType.java:41)
org.hibernate.type.NullableType.nullSafeGet(NullableType.java:184)
org.hibernate.type.NullableType.nullSafeGet(NullableType.java:173)
org.hibernate.type.AbstractType.hydrate(AbstractType.java:105)
org.hibernate.persister.entity.AbstractEntityPersister.hydrate(AbstractEntityPersister.java:2124)
org.hibernate.loader.Loader.loadFromResultSet(Loader.java:1404)
org.hibernate.loader.Loader.instanceNotYetLoaded(Loader.java:1332)
org.hibernate.loader.Loader.getRow(Loader.java:1230)
org.hibernate.loader.Loader.getRowFromResultSet(Loader.java:603)
org.hibernate.loader.Loader.doQuery(Loader.java:724)
org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:259)
org.hibernate.loader.Loader.doList(Loader.java:2228)
org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2125)
org.hibernate.loader.Loader.list(Loader.java:2120)
org.hibernate.loader.hql.QueryLoader.list(QueryLoader.java:401)
org.hibernate.hql.ast.QueryTranslatorImpl.list(QueryTranslatorImpl.java:361)
org.hibernate.engine.query.HQLQueryPlan.performList(HQLQueryPlan.java:196)
org.hibernate.impl.SessionImpl.list(SessionImpl.java:1148)
org.hibernate.impl.QueryImpl.list(QueryImpl.java:102)
com.metropro.eps.dao.impl.NewlyAddedDevicesDaoImpl.getSeriesDevices(NewlyAddedDevicesDaoImpl.java:83)
com.metropro.eps.bo.impl.NewlyAddedDevicesBoImpl.getSeriesDevices(NewlyAddedDevicesBoImpl.java:49)
com.metropro.eps.controller.RepositoryController.getSeriesDevices(RepositoryController.java:105)
sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
java.lang.reflect.Method.invoke(Unknown Source)
org.springframework.web.bind.annotation.support.HandlerMethodInvoker.invokeHandlerMethod(HandlerMethodInvoker.java:176)
org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.invokeHandlerMethod(AnnotationMethodHandlerAdapter.java:426)
org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.handle(AnnotationMethodHandlerAdapter.java:414)
org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:790)
org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:719)
org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:644)
org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:549)
javax.servlet.http.HttpServlet.service(HttpServlet.java:621)
javax.servlet.http.HttpServlet.service(HttpServlet.java:728)

错误3：

exception

org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.hibernate.exception.GenericJDBCException: could not execute query
org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:656)
org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:549)
javax.servlet.http.HttpServlet.service(HttpServlet.java:621)
javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
root cause

org.hibernate.exception.GenericJDBCException: could not execute query
org.hibernate.exception.SQLStateConverter.handledNonSpecificException(SQLStateConverter.java:126)
org.hibernate.exception.SQLStateConverter.convert(SQLStateConverter.java:114)
org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:66)
org.hibernate.loader.Loader.doList(Loader.java:2231)
org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2125)
org.hibernate.loader.Loader.list(Loader.java:2120)
org.hibernate.loader.hql.QueryLoader.list(QueryLoader.java:401)
org.hibernate.hql.ast.QueryTranslatorImpl.list(QueryTranslatorImpl.java:361)
org.hibernate.engine.query.HQLQueryPlan.performList(HQLQueryPlan.java:196)
org.hibernate.impl.SessionImpl.list(SessionImpl.java:1148)
org.hibernate.impl.QueryImpl.list(QueryImpl.java:102)
com.metropro.eps.dao.impl.NewlyAddedDevicesDaoImpl.getSeriesDevices(NewlyAddedDevicesDaoImpl.java:81)
com.metropro.eps.bo.impl.NewlyAddedDevicesBoImpl.getSeriesDevices(NewlyAddedDevicesBoImpl.java:49)
com.metropro.eps.controller.RepositoryController.getSeriesDevices(RepositoryController.java:105)
sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
java.lang.reflect.Method.invoke(Unknown Source)
org.springframework.web.bind.annotation.support.HandlerMethodInvoker.invokeHandlerMethod(HandlerMethodInvoker.java:176)
org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.invokeHandlerMethod(AnnotationMethodHandlerAdapter.java:426)
org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.handle(AnnotationMethodHandlerAdapter.java:414)
org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:790)
org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:719)
org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:644)
org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:549)
javax.servlet.http.HttpServlet.service(HttpServlet.java:621)
javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
root cause

java.sql.SQLException: Operation not allowed after ResultSet closed
com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1075)
com.mysql.jdbc.SQLError.createSQLException(SQLError.java:989)
com.mysql.jdbc.SQLError.createSQLException(SQLError.java:984)
com.mysql.jdbc.SQLError.createSQLException(SQLError.java:929)
com.mysql.jdbc.ResultSetImpl.checkClosed(ResultSetImpl.java:795)
com.mysql.jdbc.ResultSetImpl.findColumn(ResultSetImpl.java:1106)
com.mysql.jdbc.ResultSetImpl.getLong(ResultSetImpl.java:3022)
com.mchange.v2.c3p0.impl.NewProxyResultSet.getLong(NewProxyResultSet.java:2625)
org.hibernate.type.LongType.get(LongType.java:51)
org.hibernate.type.NullableType.nullSafeGet(NullableType.java:184)
org.hibernate.type.NullableType.nullSafeGet(NullableType.java:173)
org.hibernate.loader.Loader.getKeyFromResultSet(Loader.java:1121)
org.hibernate.loader.Loader.getRowFromResultSet(Loader.java:588)
org.hibernate.loader.Loader.doQuery(Loader.java:724)
org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:259)
org.hibernate.loader.Loader.doList(Loader.java:2228)
org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2125)
org.hibernate.loader.Loader.list(Loader.java:2120)
org.hibernate.loader.hql.QueryLoader.list(QueryLoader.java:401)
org.hibernate.hql.ast.QueryTranslatorImpl.list(QueryTranslatorImpl.java:361)
org.hibernate.engine.query.HQLQueryPlan.performList(HQLQueryPlan.java:196)
org.hibernate.impl.SessionImpl.list(SessionImpl.java:1148)
org.hibernate.impl.QueryImpl.list(QueryImpl.java:102)
com.metropro.eps.dao.impl.NewlyAddedDevicesDaoImpl.getSeriesDevices(NewlyAddedDevicesDaoImpl.java:81)
com.metropro.eps.bo.impl.NewlyAddedDevicesBoImpl.getSeriesDevices(NewlyAddedDevicesBoImpl.java:49)
com.metropro.eps.controller.RepositoryController.getSeriesDevices(RepositoryController.java:105)
sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
java.lang.reflect.Method.invoke(Unknown Source)
org.springframework.web.bind.annotation.support.HandlerMethodInvoker.invokeHandlerMethod(HandlerMethodInvoker.java:176)
org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.invokeHandlerMethod(AnnotationMethodHandlerAdapter.java:426)
org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.handle(AnnotationMethodHandlerAdapter.java:414)
org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:790)
org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:719)
org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:644)
org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:549)
javax.servlet.http.HttpServlet.service(HttpServlet.java:621)
javax.servlet.http.HttpServlet.service(HttpServlet.java:728)

错误4：

exception

org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.hibernate.exception.GenericJDBCException: could not execute query
org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:656)
org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:549)
javax.servlet.http.HttpServlet.service(HttpServlet.java:621)
javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
root cause

org.hibernate.exception.GenericJDBCException: could not execute query
org.hibernate.exception.SQLStateConverter.handledNonSpecificException(SQLStateConverter.java:126)
org.hibernate.exception.SQLStateConverter.convert(SQLStateConverter.java:114)
org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:66)
org.hibernate.loader.Loader.doList(Loader.java:2231)
org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2125)
org.hibernate.loader.Loader.list(Loader.java:2120)
org.hibernate.loader.hql.QueryLoader.list(QueryLoader.java:401)
org.hibernate.hql.ast.QueryTranslatorImpl.list(QueryTranslatorImpl.java:361)
org.hibernate.engine.query.HQLQueryPlan.performList(HQLQueryPlan.java:196)
org.hibernate.impl.SessionImpl.list(SessionImpl.java:1148)
org.hibernate.impl.QueryImpl.list(QueryImpl.java:102)
com.metropro.eps.dao.impl.NewlyAddedDevicesDaoImpl.getSeriesDevices(NewlyAddedDevicesDaoImpl.java:81)
com.metropro.eps.bo.impl.NewlyAddedDevicesBoImpl.getSeriesDevices(NewlyAddedDevicesBoImpl.java:49)
com.metropro.eps.controller.RepositoryController.getSeriesDevices(RepositoryController.java:105)
sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
java.lang.reflect.Method.invoke(Unknown Source)
org.springframework.web.bind.annotation.support.HandlerMethodInvoker.invokeHandlerMethod(HandlerMethodInvoker.java:176)
org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.invokeHandlerMethod(AnnotationMethodHandlerAdapter.java:426)
org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.handle(AnnotationMethodHandlerAdapter.java:414)
org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:790)
org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:719)
org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:644)
org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:549)
javax.servlet.http.HttpServlet.service(HttpServlet.java:621)
javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
root cause

java.sql.SQLException: You can't operate on a closed Connection!!!com.mchange.v2.sql.SqlUtils.toSQLException(SqlUtils.java:106)
com.mchange.v2.sql.SqlUtils.toSQLException(SqlUtils.java:65)
com.mchange.v2.c3p0.impl.NewProxyConnection.prepareStatement(NewProxyConnection.java:222)
org.hibernate.jdbc.AbstractBatcher.getPreparedStatement(AbstractBatcher.java:534)
org.hibernate.jdbc.AbstractBatcher.getPreparedStatement(AbstractBatcher.java:452)
org.hibernate.jdbc.AbstractBatcher.prepareQueryStatement(AbstractBatcher.java:161)
org.hibernate.loader.Loader.prepareQueryStatement(Loader.java:1573)
org.hibernate.loader.Loader.doQuery(Loader.java:696)
org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:259)
org.hibernate.loader.Loader.doList(Loader.java:2228)
org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2125)
org.hibernate.loader.Loader.list(Loader.java:2120)
org.hibernate.loader.hql.QueryLoader.list(QueryLoader.java:401)
org.hibernate.hql.ast.QueryTranslatorImpl.list(QueryTranslatorImpl.java:361)
org.hibernate.engine.query.HQLQueryPlan.performList(HQLQueryPlan.java:196)
org.hibernate.impl.SessionImpl.list(SessionImpl.java:1148)
org.hibernate.impl.QueryImpl.list(QueryImpl.java:102)
com.metropro.eps.dao.impl.NewlyAddedDevicesDaoImpl.getSeriesDevices(NewlyAddedDevicesDaoImpl.java:81)
com.metropro.eps.bo.impl.NewlyAddedDevicesBoImpl.getSeriesDevices(NewlyAddedDevicesBoImpl.java:49)
com.metropro.eps.controller.RepositoryController.getSeriesDevices(RepositoryController.java:105)
sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
java.lang.reflect.Method.invoke(Unknown Source)
org.springframework.web.bind.annotation.support.HandlerMethodInvoker.invokeHandlerMethod(HandlerMethodInvoker.java:176)
org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.invokeHandlerMethod(AnnotationMethodHandlerAdapter.java:426)
org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.handle(AnnotationMethodHandlerAdapter.java:414)
org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:790)
org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:719)
org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:644)
org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:549)
javax.servlet.http.HttpServlet.service(HttpServlet.java:621)
javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
root cause

java.lang.NullPointerExceptioncom.mchange.v2.c3p0.impl.NewProxyConnection.prepareStatement(NewProxyConnection.java:186)
org.hibernate.jdbc.AbstractBatcher.getPreparedStatement(AbstractBatcher.java:534)
org.hibernate.jdbc.AbstractBatcher.getPreparedStatement(AbstractBatcher.java:452)
org.hibernate.jdbc.AbstractBatcher.prepareQueryStatement(AbstractBatcher.java:161)
org.hibernate.loader.Loader.prepareQueryStatement(Loader.java:1573)
org.hibernate.loader.Loader.doQuery(Loader.java:696)
org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:259)
org.hibernate.loader.Loader.doList(Loader.java:2228)
org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2125)
org.hibernate.loader.Loader.list(Loader.java:2120)
org.hibernate.loader.hql.QueryLoader.list(QueryLoader.java:401)
org.hibernate.hql.ast.QueryTranslatorImpl.list(QueryTranslatorImpl.java:361)
org.hibernate.engine.query.HQLQueryPlan.performList(HQLQueryPlan.java:196)
org.hibernate.impl.SessionImpl.list(SessionImpl.java:1148)
org.hibernate.impl.QueryImpl.list(QueryImpl.java:102)
com.metropro.eps.dao.impl.NewlyAddedDevicesDaoImpl.getSeriesDevices(NewlyAddedDevicesDaoImpl.java:81)
com.metropro.eps.bo.impl.NewlyAddedDevicesBoImpl.getSeriesDevices(NewlyAddedDevicesBoImpl.java:49)
com.metropro.eps.controller.RepositoryController.getSeriesDevices(RepositoryController.java:105)
sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
java.lang.reflect.Method.invoke(Unknown Source)
org.springframework.web.bind.annotation.support.HandlerMethodInvoker.invokeHandlerMethod(HandlerMethodInvoker.java:176)
org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.invokeHandlerMethod(AnnotationMethodHandlerAdapter.java:426)
org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.handle(AnnotationMethodHandlerAdapter.java:414)
org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:790)
org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:719)
org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:644)
org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:549)
javax.servlet.http.HttpServlet.service(HttpServlet.java:621)
javax.servlet.http.HttpServlet.service(HttpServlet.java:728)

---

似乎是由

newlyaddevicesdaoimpl

第81/83/85行中的NullPointerException引起的。
检查堆栈跟踪以查找对域类（非框架）的引用

样本：

com.metropro.eps.dao.impl.NewlyAddedDevicesDaoImpl.getSeriesDevices(NewlyAddedDevicesDaoImpl.java:81)
com.metropro.eps.bo.impl.NewlyAddedDevicesBoImpl.getSeriesDevices(NewlyAddedDevicesBoImpl.java:49)
com.metropro.eps.controller.RepositoryController.getSeriesDevices(RepositoryController.java:105)

在

newlyaddevicesdaoimpl.getSeriesDevices（）

的请求处添加日志语句，以检查数据中的值，确保未使用空值。
最好在Controller/BoImpl中添加log语句，以检查DTO中的值在每一层上是如何填充/更改的

确保在

newlyaddedevicesdaoimpl.getSeriesDevices（）

中未取消引用空值

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如果可能，请在每次hibernate事务后检查是否关闭会话。我有一个类似的问题，并且正在“随机”获取异常org.hibernate.exception.genericjdbception:无法执行查询。在一个地方，我没有关闭会话，所以我达到了数据库中打开事务的极限。我刚刚添加了sessionFactory.getCurrentSession（）.close（）；这就解决了我的问题。

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如果您能提供一些dao实现的代码，这将非常有帮助

它的背部很长。是的，会话并非每次都关闭。我6个月前就退出了那个项目，所以我再也找不到它的代码了。无论如何，我接受了你的答案，投了赞成票。如果你认为这是一个好问题，请把这个问题也投上一票。