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JPA查詢失敗，連接丟失

2011-06-10 137 views
2

因此，當Oracle數據庫拋出SQL異常時，EntityManager關閉事務時出現問題。JPA查詢失敗，連接丟失

Caused by: java.sql.SQLException: ORA-01722: invalid number

我在數據庫中有一個SQL數據驗證規則的集合，我在下面的代碼中追加到我的SQL查詢中。查詢比 針對EAV（實體，屬性，值）數據庫表在數據庫上運行這些規則。

數據規則的示例。

t1.attribute_name = 'ATTRIBUTE_NAME' and (cast(t1.value as number) < 1 or cast(t1.value as number) > 2)

現在，因爲該表是EAV基表所有我們所處理的數據是字符串格式，但是如果你比較數字 比較完成的基礎上字符串而不是數字。這不是我們想要的，所以我們將這些數字正確地進行比較。 但是，如果EAV表中的數據不是數字，例如12A（這是完全有效的，因爲還有其他的 檢查被執行以通知用戶該無效的數據類型情況），這會導致問題。除了我們上面提到的例外，都失敗了

現在查詢失敗是很好的原因，顯然，我們無法運行它，因爲它試圖對它無法做的數據做些什麼。但是，由於需要運行的規則集合有 ，我希望在檢測到某個規則失敗後繼續運行規則。這是問題 發生的地方。

當規則查詢失敗並被異常處理程序捕獲時，由於事務已關閉，我無法繼續使用注入到bean 中的實體管理器。

我試圖在catch塊中獲得一個新的實體管理器，但是我沒有太多的運氣。我想獲得的EntityManagerFactory，並從那裏創建 一個新的EntityManager，但是當我獲得會話工廠它規定如下，

11:24:13,800 INFO [TransactionFactoryFactory] Transaction strategy: org.hibernate.ejb.transaction.JoinableCMTTransactionFactory 
11:24:13,801 INFO [TransactionManagerLookupFactory] instantiating TransactionManagerLookup: org.hibernate.transaction.JBossTransactionManagerLookup 
11:24:13,801 INFO [TransactionManagerLookupFactory] instantiated TransactionManagerLookup 
11:24:13,801 INFO [SettingsFactory] Automatic flush during beforeCompletion(): disabled 
11:24:13,801 INFO [SettingsFactory] Automatic session close at end of transaction: disabled 
11:24:13,801 INFO [SettingsFactory] JDBC batch size: 15 
11:24:13,801 INFO [SettingsFactory] JDBC batch updates for versioned data: disabled 
11:24:13,802 INFO [SettingsFactory] Scrollable result sets: enabled 
11:24:13,802 INFO [SettingsFactory] JDBC3 getGeneratedKeys(): disabled 
11:24:13,802 INFO [SettingsFactory] Connection release mode: auto 
11:24:13,802 INFO [SettingsFactory] Default schema: SCHEMA_NAME 
11:24:13,802 INFO [SettingsFactory] Default batch fetch size: 1 
11:24:13,802 INFO [SettingsFactory] Generate SQL with comments: disabled 
11:24:13,802 INFO [SettingsFactory] Order SQL updates by primary key: disabled 
11:24:13,802 INFO [SettingsFactory] Order SQL inserts for batching: disabled 
11:24:13,802 INFO [SettingsFactory] Query translator: org.hibernate.hql.ast.ASTQueryTranslatorFactory 
11:24:13,802 INFO [ASTQueryTranslatorFactory] Using ASTQueryTranslatorFactory 
11:24:13,802 INFO [SettingsFactory] Query language substitutions: {} 
11:24:13,802 INFO [SettingsFactory] JPA-QL strict compliance: enabled 
11:24:13,802 INFO [SettingsFactory] Second-level cache: enabled 
11:24:13,802 INFO [SettingsFactory] Query cache: disabled 
11:24:13,802 INFO [SettingsFactory] Cache region factory : org.hibernate.cache.impl.NoCachingRegionFactory 
11:24:13,803 INFO [SettingsFactory] Optimize cache for minimal puts: disabled 
11:24:13,803 INFO [SettingsFactory] Structured second-level cache entries: disabled 
11:24:13,803 INFO [SettingsFactory] Statistics: disabled 
11:24:13,803 INFO [SettingsFactory] Deleted entity synthetic identifier rollback: disabled 
11:24:13,803 INFO [SettingsFactory] Default entity-mode: pojo 
11:24:13,803 INFO [SettingsFactory] Named query checking : enabled 
11:24:13,813 INFO [SessionFactoryImpl] building session factory 
11:24:13,813 INFO [SessionFactoryObjectFactory] Not binding factory to JNDI, no JNDI name configured 
11:24:13,813 INFO [SchemaValidator] Running schema validator 
11:24:13,813 INFO [SchemaValidator] fetching database metadata 
11:24:14,156 INFO [NamingHelper] JNDI InitialContext properties:{}

但是當我嘗試運行查詢，一旦我已經從創建的新的EntityManager工廠，我得到以下例外。

11:25:11,128 ERROR [STDERR] javax.persistence.PersistenceException: org.hibernate.MappingException: Unknown entity: org.myprogram.entity.MisCollVariableValue 
11:25:11,129 ERROR [STDERR]  at org.hibernate.ejb.AbstractEntityManagerImpl.throwPersistenceException(AbstractEntityManagerImpl.java:614) 
11:25:11,129 ERROR [STDERR]  at org.hibernate.ejb.QueryImpl.getResultList(QueryImpl.java:76) 
11:25:11,129 ERROR [STDERR]  at org.myprogram.dataloader.DataValidator.validateInputRules(DataValidator.java:444) 
11:25:11,129 ERROR [STDERR]  at org.myprogram.dataloader.DataValidator.methodThatCallsThePrivateOne(DataValidator.java:124) 
11:25:11,129 ERROR [STDERR]  at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) 
11:25:11,129 ERROR [STDERR]  at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) 
11:25:11,129 ERROR [STDERR]  at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) 
11:25:11,129 ERROR [STDERR]  at java.lang.reflect.Method.invoke(Unknown Source) 
11:25:11,129 ERROR [STDERR]  at org.jboss.seam.util.Reflections.invoke(Reflections.java:22) 
11:25:11,129 ERROR [STDERR]  at org.jboss.seam.intercept.RootInvocationContext.proceed(RootInvocationContext.java:32) 
11:25:11,129 ERROR [STDERR]  at org.jboss.seam.intercept.SeamInvocationContext.proceed(SeamInvocationContext.java:56) 
11:25:11,129 ERROR [STDERR]  at org.jboss.seam.transaction.RollbackInterceptor.aroundInvoke(RollbackInterceptor.java:28) 
11:25:11,129 ERROR [STDERR]  at org.jboss.seam.intercept.SeamInvocationContext.proceed(SeamInvocationContext.java:68) 
11:25:11,129 ERROR [STDERR]  at org.jboss.seam.core.BijectionInterceptor.aroundInvoke(BijectionInterceptor.java:77) 
11:25:11,129 ERROR [STDERR]  at org.jboss.seam.intercept.SeamInvocationContext.proceed(SeamInvocationContext.java:68) 
11:25:11,129 ERROR [STDERR]  at org.jboss.seam.core.MethodContextInterceptor.aroundInvoke(MethodContextInterceptor.java:44) 
11:25:11,129 ERROR [STDERR]  at org.jboss.seam.intercept.SeamInvocationContext.proceed(SeamInvocationContext.java:68) 
11:25:11,129 ERROR [STDERR]  at org.jboss.seam.intercept.RootInterceptor.invoke(RootInterceptor.java:107) 
11:25:11,129 ERROR [STDERR]  at org.jboss.seam.intercept.JavaBeanInterceptor.interceptInvocation(JavaBeanInterceptor.java:185) 
11:25:11,129 ERROR [STDERR]  at org.jboss.seam.intercept.JavaBeanInterceptor.invoke(JavaBeanInterceptor.java:103) 
11:25:11,129 ERROR [STDERR]  at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) 
11:25:11,130 ERROR [STDERR]  at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) 
11:25:11,130 ERROR [STDERR]  at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) 
11:25:11,130 ERROR [STDERR]  at java.lang.reflect.Method.invoke(Unknown Source) 
11:25:11,130 ERROR [STDERR]  at org.jboss.seam.util.Reflections.invoke(Reflections.java:22) 
11:25:11,130 ERROR [STDERR]  at org.jboss.seam.intercept.RootInvocationContext.proceed(RootInvocationContext.java:32) 
11:25:11,130 ERROR [STDERR]  at org.jboss.seam.intercept.SeamInvocationContext.proceed(SeamInvocationContext.java:56) 
11:25:11,130 ERROR [STDERR]  at org.jboss.seam.transaction.RollbackInterceptor.aroundInvoke(RollbackInterceptor.java:28) 
11:25:11,130 ERROR [STDERR]  at org.jboss.seam.intercept.SeamInvocationContext.proceed(SeamInvocationContext.java:68) 
11:25:11,130 ERROR [STDERR]  at org.jboss.seam.core.BijectionInterceptor.aroundInvoke(BijectionInterceptor.java:77) 
11:25:11,130 ERROR [STDERR]  at org.jboss.seam.intercept.SeamInvocationContext.proceed(SeamInvocationContext.java:68) 
11:25:11,130 ERROR [STDERR]  at org.jboss.seam.core.MethodContextInterceptor.aroundInvoke(MethodContextInterceptor.java:44) 
11:25:11,130 ERROR [STDERR]  at org.jboss.seam.intercept.SeamInvocationContext.proceed(SeamInvocationContext.java:68) 
11:25:11,130 ERROR [STDERR]  at org.jboss.seam.intercept.RootInterceptor.invoke(RootInterceptor.java:107) 
11:25:11,130 ERROR [STDERR]  at org.jboss.seam.intercept.JavaBeanInterceptor.interceptInvocation(JavaBeanInterceptor.java:185) 
11:25:11,130 ERROR [STDERR]  at org.jboss.seam.intercept.JavaBeanInterceptor.invoke(JavaBeanInterceptor.java:103) 
11:25:11,130 ERROR [STDERR]  at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) 
11:25:11,130 ERROR [STDERR]  at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) 
11:25:11,130 ERROR [STDERR]  at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) 
11:25:11,130 ERROR [STDERR]  at java.lang.reflect.Method.invoke(Unknown Source) 
11:25:11,130 ERROR [STDERR]  at org.jboss.el.util.ReflectionUtil.invokeMethod(ReflectionUtil.java:335) 
11:25:11,130 ERROR [STDERR]  at org.jboss.el.util.ReflectionUtil.invokeMethod(ReflectionUtil.java:348) 
11:25:11,130 ERROR [STDERR]  at org.jboss.el.parser.AstPropertySuffix.invoke(AstPropertySuffix.java:58) 
11:25:11,130 ERROR [STDERR]  at org.jboss.el.parser.AstValue.invoke(AstValue.java:96) 
11:25:11,130 ERROR [STDERR]  at org.jboss.el.MethodExpressionImpl.invoke(MethodExpressionImpl.java:276) 
11:25:11,130 ERROR [STDERR]  at com.sun.facelets.el.TagMethodExpression.invoke(TagMethodExpression.java:68) 
11:25:11,130 ERROR [STDERR]  at javax.faces.component.MethodBindingMethodExpressionAdapter.invoke(MethodBindingMethodExpressionAdapter.java:88) 
11:25:11,130 ERROR [STDERR]  at com.sun.faces.application.ActionListenerImpl.processAction(ActionListenerImpl.java:102) 
11:25:11,131 ERROR [STDERR]  at javax.faces.component.UICommand.broadcast(UICommand.java:387) 
11:25:11,131 ERROR [STDERR]  at org.ajax4jsf.component.UIDataAdaptor.broadcast(UIDataAdaptor.java:1364) 
11:25:11,131 ERROR [STDERR]  at org.ajax4jsf.component.AjaxViewRoot.processEvents(AjaxViewRoot.java:321) 
11:25:11,131 ERROR [STDERR]  at org.ajax4jsf.component.AjaxViewRoot.broadcastEvents(AjaxViewRoot.java:296) 
11:25:11,131 ERROR [STDERR]  at org.ajax4jsf.component.AjaxViewRoot.processPhase(AjaxViewRoot.java:253) 
11:25:11,131 ERROR [STDERR]  at org.ajax4jsf.component.AjaxViewRoot.processApplication(AjaxViewRoot.java:466) 
11:25:11,131 ERROR [STDERR]  at com.sun.faces.lifecycle.InvokeApplicationPhase.execute(InvokeApplicationPhase.java:82) 
11:25:11,131 ERROR [STDERR]  at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:100) 
11:25:11,131 ERROR [STDERR]  at com.sun.faces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:118) 
11:25:11,131 ERROR [STDERR]  at javax.faces.webapp.FacesServlet.service(FacesServlet.java:265) 
11:25:11,131 ERROR [STDERR]  at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290) 
11:25:11,131 ERROR [STDERR]  at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) 
11:25:11,131 ERROR [STDERR]  at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:83) 
11:25:11,131 ERROR [STDERR]  at org.jboss.seam.web.IdentityFilter.doFilter(IdentityFilter.java:40) 
11:25:11,131 ERROR [STDERR]  at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69) 
11:25:11,131 ERROR [STDERR]  at org.jboss.seam.web.MultipartFilter.doFilter(MultipartFilter.java:90) 
11:25:11,131 ERROR [STDERR]  at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69) 
11:25:11,131 ERROR [STDERR]  at org.jboss.seam.web.ExceptionFilter.doFilter(ExceptionFilter.java:64) 
11:25:11,131 ERROR [STDERR]  at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69) 
11:25:11,131 ERROR [STDERR]  at org.jboss.seam.web.RedirectFilter.doFilter(RedirectFilter.java:45) 
11:25:11,131 ERROR [STDERR]  at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69) 
11:25:11,131 ERROR [STDERR]  at org.ajax4jsf.webapp.BaseXMLFilter.doXmlFilter(BaseXMLFilter.java:178) 
11:25:11,131 ERROR [STDERR]  at org.ajax4jsf.webapp.BaseFilter.handleRequest(BaseFilter.java:290) 
11:25:11,131 ERROR [STDERR]  at org.ajax4jsf.webapp.BaseFilter.processUploadsAndHandleRequest(BaseFilter.java:368) 
11:25:11,131 ERROR [STDERR]  at org.ajax4jsf.webapp.BaseFilter.doFilter(BaseFilter.java:495) 
11:25:11,131 ERROR [STDERR]  at org.jboss.seam.web.Ajax4jsfFilter.doFilter(Ajax4jsfFilter.java:56) 
11:25:11,131 ERROR [STDERR]  at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69) 
11:25:11,132 ERROR [STDERR]  at org.jboss.seam.web.LoggingFilter.doFilter(LoggingFilter.java:60) 
11:25:11,132 ERROR [STDERR]  at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69) 
11:25:11,133 ERROR [STDERR]  at org.jboss.seam.web.HotDeployFilter.doFilter(HotDeployFilter.java:53) 
11:25:11,133 ERROR [STDERR]  at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69) 
11:25:11,133 ERROR [STDERR]  at org.jboss.seam.servlet.SeamFilter.doFilter(SeamFilter.java:158) 
11:25:11,133 ERROR [STDERR]  at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235) 
11:25:11,133 ERROR [STDERR]  at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) 
11:25:11,133 ERROR [STDERR]  at org.jboss.web.tomcat.filters.ReplyHeaderFilter.doFilter(ReplyHeaderFilter.java:96) 
11:25:11,133 ERROR [STDERR]  at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235) 
11:25:11,134 ERROR [STDERR]  at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) 
11:25:11,134 ERROR [STDERR]  at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:235) 
11:25:11,134 ERROR [STDERR]  at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191) 
11:25:11,134 ERROR [STDERR]  at org.jboss.web.tomcat.security.SecurityAssociationValve.invoke(SecurityAssociationValve.java:190) 
11:25:11,134 ERROR [STDERR]  at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:433) 
11:25:11,134 ERROR [STDERR]  at org.jboss.web.tomcat.security.JaccContextValve.invoke(JaccContextValve.java:92) 
11:25:11,134 ERROR [STDERR]  at org.jboss.web.tomcat.security.SecurityContextEstablishmentValve.process(SecurityContextEstablishmentValve.java:126) 
11:25:11,134 ERROR [STDERR]  at org.jboss.web.tomcat.security.SecurityContextEstablishmentValve.invoke(SecurityContextEstablishmentValve.java:70) 
11:25:11,134 ERROR [STDERR]  at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127) 
11:25:11,134 ERROR [STDERR]  at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102) 
11:25:11,134 ERROR [STDERR]  at org.jboss.web.tomcat.service.jca.CachedConnectionValve.invoke(CachedConnectionValve.java:158) 
11:25:11,134 ERROR [STDERR]  at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109) 
11:25:11,134 ERROR [STDERR]  at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:330) 
11:25:11,134 ERROR [STDERR]  at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:829) 
11:25:11,134 ERROR [STDERR]  at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:598) 
11:25:11,134 ERROR [STDERR]  at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:447) 
11:25:11,134 ERROR [STDERR]  at java.lang.Thread.run(Unknown Source) 
11:25:11,135 ERROR [STDERR] Caused by: org.hibernate.MappingException: Unknown entity: org.myprogram.entity.MisCollVariableValue 
11:25:11,135 ERROR [STDERR]  at org.hibernate.impl.SessionFactoryImpl.getEntityPersister(SessionFactoryImpl.java:628) 
11:25:11,135 ERROR [STDERR]  at org.hibernate.loader.custom.sql.SQLQueryReturnProcessor.getSQLLoadable(SQLQueryReturnProcessor.java:335) 
11:25:11,135 ERROR [STDERR]  at org.hibernate.loader.custom.sql.SQLQueryReturnProcessor.processRootReturn(SQLQueryReturnProcessor.java:376) 
11:25:11,135 ERROR [STDERR]  at org.hibernate.loader.custom.sql.SQLQueryReturnProcessor.processReturn(SQLQueryReturnProcessor.java:355) 
11:25:11,135 ERROR [STDERR]  at org.hibernate.loader.custom.sql.SQLQueryReturnProcessor.process(SQLQueryReturnProcessor.java:171) 
11:25:11,135 ERROR [STDERR]  at org.hibernate.loader.custom.sql.SQLCustomQuery.<init>(SQLCustomQuery.java:87) 
11:25:11,135 ERROR [STDERR]  at org.hibernate.engine.query.NativeSQLQueryPlan.<init>(NativeSQLQueryPlan.java:67) 
11:25:11,135 ERROR [STDERR]  at org.hibernate.engine.query.QueryPlanCache.getNativeSQLQueryPlan(QueryPlanCache.java:136) 
11:25:11,135 ERROR [STDERR]  at org.hibernate.impl.AbstractSessionImpl.getNativeSQLQueryPlan(AbstractSessionImpl.java:160) 
11:25:11,135 ERROR [STDERR]  at org.hibernate.impl.AbstractSessionImpl.list(AbstractSessionImpl.java:165) 
11:25:11,135 ERROR [STDERR]  at org.hibernate.impl.SQLQueryImpl.list(SQLQueryImpl.java:175) 
11:25:11,135 ERROR [STDERR]  at org.hibernate.ejb.QueryImpl.getResultList(QueryImpl.java:67) 
11:25:11,135 ERROR [STDERR]  ... 102 more

所以我想我的問題是，

  • 是否有可能獲得的EntityManagerFactory，並得到一個新的EntityManger，這樣我可以繼續運行我的查詢規則。
  • 如果是這樣，爲什麼（因爲我不知道爲什麼它不知道實體）？
  • 這是一個很好的方法來解決我的問題，還是我以這種錯誤的方式？

我希望我已經清楚。乾杯。

@Name("dataValidator") 
@Scope(ScopeType.CONVERSATION) 
@AutoCreate 
public class DataValidator implements DataValidatorIntf { 

    @Logger private Log log; 

    @In EntityManager entityManager; 

    public void methodThatCallsThePrivateOne() { 
    validateInputRules(); 
    } 

    private void validateInputRules() { 
    if (fInputRules == null) { 
     MdInputRuleList mdInputRuleList = (MdInputRuleList) Component.getInstance(MdInputRuleList.class, true); 
     fInputRules = mdInputRuleList.getResultList(); 
    } 

    // This is my query, which can fail. 
    String sql = 
     " select " + 
     " t2.coll_var_value_id, " + 
     " t2.attribute_name, " + 
     " t2.load_id, " + 
     " t2.coll_variable_id, " + 
     " t2.collection_id, " + 
     " t2.source_file_line, " + 
     " t2.value " + 
     " from " + 
     " mis_coll_variable_value t1 " + 
     " inner join mis_coll_variable_value t2 on t2.source_file_line = t1.source_file_line " + 
     "  and t2.load_id = :pLoadId " + 
     " where " + 
     " t1.load_id = :pLoadId " + 
     " and %s " + 
     " order by " + 
     " t1.source_file_line," + 
     " t1.coll_variable_id " 
    ; 

    fInputRulesViolations = new HashMap<Long, List<MisCollVariableValue>>(); 

    for (MdInputRule mdInputRule : fInputRules) { 
     Query query = entityManager.createNativeQuery(
     String.format(sql, mdInputRule.getRuleSql()), 
     MisCollVariableValue.class 
    ); 
     query.setParameter("pLoadId", fLoadToValidate.getLoadId()); 

     try { 
     if (!fInputRulesViolations.containsKey(mdInputRule.getInputRuleId())) { 
      fInputRulesViolations.put(mdInputRule.getInputRuleId(), null); 
     } 

     fInputRulesViolations.put(
      mdInputRule.getInputRuleId(), 
      query.getResultList() 
     ); 
     } catch (Exception ex) { 
     log.info("Input Rule #0 [Id #1] failed", mdInputRule.getRuleid(), mdInputRule.getInputRuleId()); 
     ex.printStackTrace(); 

     // TODO: Try and get a new Entity Manager when a exception is thrown in this method 

     // My attempt at getting a EntityManagerFactory 

     // EntityManagerFactory myEmf = Persistence.createEntityManagerFactory("PersistenceUnitName"); 
     // entityManager = myEmf.createEntityManager(); 
     } 
    } 
    }

來源

2011-06-10 Scott

+0

是的，你想獲得一個新的EntityManager，因爲一旦事務失敗就繼續使用'EntityManager'是危險的 - 參見[Hibernate的文檔]（http://docs.jboss.org/hibernate/core/ 3.5/reference/en/html/transactions.html＃transactions-demarcation-exceptions）以獲得更詳細的解釋。我無法告訴你如何做到這一點，但我懷疑你需要深入瞭解Seam如何爲你的課程提供注入的EntityManager。 – hertzsprung 2011-06-16 23:02:34

回答

0

你總是可以通過使用

Component.getInstance("entityManager");

得到一個EntityManager但是你的實體不會被連接到Seam的持久化上下文。 我認爲你的驗證方式有問題，或者我不明白它是如何工作的，但爲什麼不使用字符串比較而不是失敗的查詢呢？

來源

2011-11-05 20:54:51 gebuh

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