在我的应用程序中,我为一项工作使用了 20 个线程。每个线程调用远程 Web 服务并更新 Oracle 数据库。 Jboss 重启后,作业无法更新数据库,除了我在日志中发现的异常:
2017-11-08 23:36:20,706 ERROR [org.hibernate.engine.jdbc.spi.SqlExceptionHelper] (EJB default - 21) javax.resource.ResourceException: IJ000460: Error checking for a transaction
2017-11-08 23:36:20,706 ERROR [org.jboss.as.ejb3] (EJB default - 16) javax.ejb.EJBTransactionRolledbackException: org.hibernate.exception.GenericJDBCException: Could not open connection
2017-11-08 23:36:20,707 ERROR [org.jboss.as.ejb3] (EJB default - 20) javax.ejb.EJBTransactionRolledbackException: org.hibernate.exception.GenericJDBCException: Could not open connection
2017-11-08 23:36:20,707 ERROR [org.jboss.as.ejb3] (EJB default - 19) javax.ejb.EJBTransactionRolledbackException: org.hibernate.exception.GenericJDBCException: Could not open connection
2017-11-08 23:36:20,710 ERROR [org.jboss.as.ejb3] (EJB default - 21) javax.ejb.EJBTransactionRolledbackException: org.hibernate.exception.GenericJDBCException: Could not open connection
2017-11-08 23:36:20,711 ERROR [org.jboss.as.ejb3.invocation] (EJB default - 16) JBAS014134: EJB Invocation failed on component PersonServiceDaoImpl for method public abstract long com.kaviletta.re.caltek.db.dao.PersonServiceDao.getNotUpdatedAddressCountBySubmissionId(int): javax.ejb.EJBTransactionRolledbackException: org.hibernate.exception.GenericJDBCException: Could not open connection
at org.jboss.as.ejb3.tx.CMTTxInterceptor.handleInCallerTx(CMTTxInterceptor.java:162) [jboss-as-ejb3-7.3.4.Final-redhat-1.jar:7.3.4.Final-redhat-1]
at org.jboss.as.ejb3.tx.CMTTxInterceptor.invokeInCallerTx(CMTTxInterceptor.java:252) [jboss-as-ejb3-7.3.4.Final-redhat-1.jar:7.3.4.Final-redhat-1]
at org.jboss.as.ejb3.tx.CMTTxInterceptor.required(CMTTxInterceptor.java:341) [jboss-as-ejb3-7.3.4.Final-redhat-1.jar:7.3.4.Final-redhat-1]
at org.jboss.as.ejb3.tx.CMTTxInterceptor.processInvocation(CMTTxInterceptor.java:238) [jboss-as-ejb3-7.3.4.Final-redhat-1.jar:7.3.4.Final-redhat-1]
at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:288) [jboss-invocation-1.1.2.Final-redhat-1.jar:1.1.2.Final-redhat-1]
at org.jboss.as.ejb3.component.interceptors.CurrentInvocationContextInterceptor.processInvocation(CurrentInvocationContextInterceptor.java:41) [jboss-as-ejb3-7.3.4.Final-redhat-1.jar:7.3.4.Final-redhat-1]
at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:288) [jboss-invocation-1.1.2.Final-redhat-1.jar:1.1.2.Final-redhat-1]
at org.jboss.as.ejb3.component.interceptors.ShutDownInterceptorFactory$1.processInvocation(ShutDownInterceptorFactory.java:64) [jboss-as-ejb3-7.3.4.Final-redhat-1.jar:7.3.4.Final-redhat-1]
at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:288) [jboss-invocation-1.1.2.Final-redhat-1.jar:1.1.2.Final-redhat-1]
at org.jboss.as.ejb3.component.interceptors.LoggingInterceptor.processInvocation(LoggingInterceptor.java:59) [jboss-as-ejb3-7.3.4.Final-redhat-1.jar:7.3.4.Final-redhat-1]
at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:288) [jboss-invocation-1.1.2.Final-redhat-1.jar:1.1.2.Final-redhat-1]
at org.jboss.as.ee.component.NamespaceContextInterceptor.processInvocation(NamespaceContextInterceptor.java:50) [jboss-as-ee-7.3.4.Final-redhat-1.jar:7.3.4.Final-redhat-1]
at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:288) [jboss-invocation-1.1.2.Final-redhat-1.jar:1.1.2.Final-redhat-1]
at org.jboss.as.ejb3.component.interceptors.AdditionalSetupInterceptor.processInvocation(AdditionalSetupInterceptor.java:55) [jboss-as-ejb3-7.3.4.Final-redhat-1.jar:7.3.4.Final-redhat-1]
at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:288) [jboss-invocation-1.1.2.Final-redhat-1.jar:1.1.2.Final-redhat-1]
at org.jboss.as.ee.component.TCCLInterceptor.processInvocation(TCCLInterceptor.java:45) [jboss-as-ee-7.3.4.Final-redhat-1.jar:7.3.4.Final-redhat-1]
at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:288) [jboss-invocation-1.1.2.Final-redhat-1.jar:1.1.2.Final-redhat-1]
at org.jboss.invocation.ChainedInterceptor.processInvocation(ChainedInterceptor.java:61) [jboss-invocation-1.1.2.Final-redhat-1.jar:1.1.2.Final-redhat-1]
at org.jboss.as.ee.component.ViewService$View.invoke(ViewService.java:165) [jboss-as-ee-7.3.4.Final-redhat-1.jar:7.3.4.Final-redhat-1]
at org.jboss.as.ee.component.ViewDescription$1.processInvocation(ViewDescription.java:182) [jboss-as-ee-7.3.4.Final-redhat-1.jar:7.3.4.Final-redhat-1]
at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:288) [jboss-invocation-1.1.2.Final-redhat-1.jar:1.1.2.Final-redhat-1]
at org.jboss.invocation.ChainedInterceptor.processInvocation(ChainedInterceptor.java:61) [jboss-invocation-1.1.2.Final-redhat-1.jar:1.1.2.Final-redhat-1]
at org.jboss.as.ee.component.ProxyInvocationHandler.invoke(ProxyInvocationHandler.java:72) [jboss-as-ee-7.3.4.Final-redhat-1.jar:7.3.4.Final-redhat-1]
at com.kaviletta.re.caltek.db.dao.PersonServiceDao$$$view6.getNotUpdatedAddressCountBySubmissionId(Unknown Source) [classes:]
at com.kaviletta.re.caltek.rest.service.impl.AsynchronousServiceImpl.asyncAddressDetails(AsynchronousServiceImpl.java:61) [classes:]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) [rt.jar:1.7.0_55]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) [rt.jar:1.7.0_55]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) [rt.jar:1.7.0_55]
at java.lang.reflect.Method.invoke(Method.java:606) [rt.jar:1.7.0_55]
at org.jboss.as.ee.component.ManagedReferenceMethodInterceptorFactory$ManagedReferenceMethodInterceptor.processInvocation(ManagedReferenceMethodInterceptorFactory.java:72) [jboss-as-ee-7.3.4.Final-redhat-1.jar:7.3.4.Final-redhat-1]
at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:288) [jboss-invocation-1.1.2.Final-redhat-1.jar:1.1.2.Final-redhat-1]
at org.jboss.invocation.WeavedInterceptor.processInvocation(WeavedInterceptor.java:53) [jboss-invocation-1.1.2.Final-redhat-1.jar:1.1.2.Final-redhat-1]
at org.jboss.as.ee.component.interceptors.UserInterceptorFactory$1.processInvocation(UserInterceptorFactory.java:58) [jboss-as-ee-7.3.4.Final-redhat-1.jar:7.3.4.Final-redhat-1]
at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:288) [jboss-invocation-1.1.2.Final-redhat-1.jar:1.1.2.Final-redhat-1]
at org.jboss.invocation.WeavedInterceptor.processInvocation(WeavedInterceptor.java:53) [jboss-invocation-1.1.2.Final-redhat-1.jar:1.1.2.Final-redhat-1]
at org.jboss.as.ee.component.interceptors.UserInterceptorFactory$1.processInvocation(UserInterceptorFactory.java:58) [jboss-as-ee-7.3.4.Final-redhat-1.jar:7.3.4.Final-redhat-1]
at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:288) [jboss-invocation-1.1.2.Final-redhat-1.jar:1.1.2.Final-redhat-1]
at org.jboss.as.ejb3.component.invocationmetrics.ExecutionTimeInterceptor.processInvocation(ExecutionTimeInterceptor.java:43) [jboss-as-ejb3-7.3.4.Final-redhat-1.jar:7.3.4.Final-redhat-1]
at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:288) [jboss-invocation-1.1.2.Final-redhat-1.jar:1.1.2.Final-redhat-1]
at org.jboss.as.jpa.interceptor.SBInvocationInterceptor.processInvocation(SBInvocationInterceptor.java:47) [jboss-as-jpa-7.3.4.Final-redhat-1.jar:7.3.4.Final-redhat-1]
at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:288) [jboss-invocation-1.1.2.Final-redhat-1.jar:1.1.2.Final-redhat-1]
at org.jboss.invocation.InitialInterceptor.processInvocation(InitialInterceptor.java:21) [jboss-invocation-1.1.2.Final-redhat-1.jar:1.1.2.Final-redhat-1]
at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:288) [jboss-invocation-1.1.2.Final-redhat-1.jar:1.1.2.Final-redhat-1]
at org.jboss.invocation.ChainedInterceptor.processInvocation(ChainedInterceptor.java:61) [jboss-invocation-1.1.2.Final-redhat-1.jar:1.1.2.Final-redhat-1]
at org.jboss.as.ee.component.interceptors.ComponentDispatcherInterceptor.processInvocation(ComponentDispatcherInterceptor.java:53) [jboss-as-ee-7.3.4.Final-redhat-1.jar:7.3.4.Final-redhat-1]
at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:288) [jboss-invocation-1.1.2.Final-redhat-1.jar:1.1.2.Final-redhat-1]
at org.jboss.as.ejb3.component.pool.PooledInstanceInterceptor.processInvocation(PooledInstanceInterceptor.java:51) [jboss-as-ejb3-7.3.4.Final-redhat-1.jar:7.3.4.Final-redhat-1]
at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:288) [jboss-invocation-1.1.2.Final-redhat-1.jar:1.1.2.Final-redhat-1]
at org.jboss.as.ejb3.tx.CMTTxInterceptor.invokeInOurTx(CMTTxInterceptor.java:272) [jboss-as-ejb3-7.3.4.Final-redhat-1.jar:7.3.4.Final-redhat-1]
at org.jboss.as.ejb3.tx.CMTTxInterceptor.required(CMTTxInterceptor.java:339) [jboss-as-ejb3-7.3.4.Final-redhat-1.jar:7.3.4.Final-redhat-1]
at org.jboss.as.ejb3.tx.CMTTxInterceptor.processInvocation(CMTTxInterceptor.java:238) [jboss-as-ejb3-7.3.4.Final-redhat-1.jar:7.3.4.Final-redhat-1]
at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:288) [jboss-invocation-1.1.2.Final-redhat-1.jar:1.1.2.Final-redhat-1]
at org.jboss.as.ejb3.component.interceptors.CurrentInvocationContextInterceptor.processInvocation(CurrentInvocationContextInterceptor.java:41) [jboss-as-ejb3-7.3.4.Final-redhat-1.jar:7.3.4.Final-redhat-1]
at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:288) [jboss-invocation-1.1.2.Final-redhat-1.jar:1.1.2.Final-redhat-1]
at org.jboss.as.ejb3.component.interceptors.ShutDownInterceptorFactory$1.processInvocation(ShutDownInterceptorFactory.java:64) [jboss-as-ejb3-7.3.4.Final-redhat-1.jar:7.3.4.Final-redhat-1]
at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:288) [jboss-invocation-1.1.2.Final-redhat-1.jar:1.1.2.Final-redhat-1]
at org.jboss.as.ejb3.component.interceptors.LoggingInterceptor.processInvocation(LoggingInterceptor.java:59) [jboss-as-ejb3-7.3.4.Final-redhat-1.jar:7.3.4.Final-redhat-1]
at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:288) [jboss-invocation-1.1.2.Final-redhat-1.jar:1.1.2.Final-redhat-1]
at org.jboss.as.ee.component.NamespaceContextInterceptor.processInvocation(NamespaceContextInterceptor.java:50) [jboss-as-ee-7.3.4.Final-redhat-1.jar:7.3.4.Final-redhat-1]
at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:288) [jboss-invocation-1.1.2.Final-redhat-1.jar:1.1.2.Final-redhat-1]
at org.jboss.as.ejb3.component.interceptors.AdditionalSetupInterceptor.processInvocation(AdditionalSetupInterceptor.java:55) [jboss-as-ejb3-7.3.4.Final-redhat-1.jar:7.3.4.Final-redhat-1]
at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:288) [jboss-invocation-1.1.2.Final-redhat-1.jar:1.1.2.Final-redhat-1]
at org.jboss.as.ee.component.TCCLInterceptor.processInvocation(TCCLInterceptor.java:45) [jboss-as-ee-7.3.4.Final-redhat-1.jar:7.3.4.Final-redhat-1]
at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:288) [jboss-invocation-1.1.2.Final-redhat-1.jar:1.1.2.Final-redhat-1]
at org.jboss.invocation.ChainedInterceptor.processInvocation(ChainedInterceptor.java:61) [jboss-invocation-1.1.2.Final-redhat-1.jar:1.1.2.Final-redhat-1]
at org.jboss.as.ee.component.ViewService$View.invoke(ViewService.java:165) [jboss-as-ee-7.3.4.Final-redhat-1.jar:7.3.4.Final-redhat-1]
at org.jboss.as.ee.component.ViewDescription$1.processInvocation(ViewDescription.java:182) [jboss-as-ee-7.3.4.Final-redhat-1.jar:7.3.4.Final-redhat-1]
at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:288) [jboss-invocation-1.1.2.Final-redhat-1.jar:1.1.2.Final-redhat-1]
at org.jboss.as.ejb3.component.interceptors.AsyncFutureInterceptorFactory$1$1.runInvocation(AsyncFutureInterceptorFactory.java:89) [jboss-as-ejb3-7.3.4.Final-redhat-1.jar:7.3.4.Final-redhat-1]
at org.jboss.as.ejb3.component.interceptors.AsyncInvocationTask.run(AsyncInvocationTask.java:73) [jboss-as-ejb3-7.3.4.Final-redhat-1.jar:7.3.4.Final-redhat-1]
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) [rt.jar:1.7.0_55]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) [rt.jar:1.7.0_55]
at java.lang.Thread.run(Thread.java:745) [rt.jar:1.7.0_55]
at org.jboss.threads.JBossThread.run(JBossThread.java:122)
Caused by: javax.persistence.PersistenceException: org.hibernate.exception.GenericJDBCException: Could not open connection
at org.hibernate.ejb.AbstractEntityManagerImpl.convert(AbstractEntityManagerImpl.java:1387) [hibernate-entitymanager-4.2.7.SP5-redhat-1.jar:4.2.7.SP5-redhat-1]
at org.hibernate.ejb.AbstractEntityManagerImpl.convert(AbstractEntityManagerImpl.java:1310) [hibernate-entitymanager-4.2.7.SP5-redhat-1.jar:4.2.7.SP5-redhat-1]
at org.hibernate.ejb.QueryImpl.getSingleResult(QueryImpl.java:316) [hibernate-entitymanager-4.2.7.SP5-redhat-1.jar:4.2.7.SP5-redhat-1]
at org.jboss.as.jpa.container.QueryNonTxInvocationDetacher.getSingleResult(QueryNonTxInvocationDetacher.java:69) [jboss-as-jpa-7.3.4.Final-redhat-1.jar:7.3.4.Final-redhat-1]
线程用于数据库操作的代码:
@PersistenceContext
EntityManager entityManager;
protected EntityManager getEntityManager() {
return entityManager;
}
protected void setEntityManager(EntityManager manager) {
this.entityManager = manager;
}
public long getNotUpdatedAddressCountBySubmissionId(int submissionId) {
Query q = getEntityManager().createQuery(
"select count(address.addressId.submissionId) from AddressStruc address where processState!=1 and address.addressId.submissionId = :submissionId");
q.setParameter("submissionId", submissionId);
return (long) q.getSingleResult();
}
public void updateStudentdAddress(List<AddressStruc> studnetsAddressDetails) {
try {
for (AddressStruc studentdAddress : studnetsAddressDetails) {
AddressStruc addressDetails = entityManager.find(AddressStruc.class, new AddressId(
studentAddress.getAddressId().getSubmissionId(), studentAddress.getAddressId().getRowId()));
if (addressDetails != null) {
entityManager.merge(updateStudentDetails(addressDetails, studentAddress));
entityManager.flush();
}
}
} catch (Exception e) {
log.error("Exception occured while updating Address(method-->updateStudentAddress))-->" + e);
}
}
异步方法调用 updateStudentAddress 方法
public AsyncResult<StudentStatusModel> asyncAddressDetails(int startRow, int noOfRecord, int submissionId) {
// method for fetching record based on the start row provided
Collection<AddressStruc> addressList = studentEjb.getAddressBySubmissionId(startRow, noOfRecord, submissionId);
StudentStatusModel status = new StudentStatusModel();
status.setStartRow(startRow);
status.setRetry(false);
status.setMessage(null);
// invoke the webservice and generate student for the given address
if (StudentUtil.webServiceFailed <= 5) {
OutputModel outputModel = invokeWebservice(addressList, status);
if ((outputModel != null) && (outputModel.getStudentModels().size() > 0)) {
// update the address details based on the submissionId+rowId
studentEjb.updateStudentAddress(new ArrayList<>(convertModelToEntity(outputModel).values()));
}
}
return new AsyncResult<StudentStatusModel>(status);
}
我正在使用容器管理的实体管理器进行数据库转换。
每个线程调用 updateStudentAddress 方法并更新 100 条记录。
由于这个作业是一个长时间运行的作业,一段时间后 jboss 无法与 oracle 建立进一步的连接。
有什么办法可以解决这个问题吗?
最佳答案
我觉得问题可能是里面的异常处理:asyncAddressDetails
在 RuntimeException 或 ApplicationException 导致事务回滚后,我们在 jboss7 中发生了此错误,当捕获到此异常时,应用程序代码随后在当前事务上下文完成之前对 EntityManager 进行了进一步操作。
例子:
void methodInNewTransaction() {
try {
dao.inRequiredTransaction();
} catch (RuntimeException ex) {
; // ignore it
}
dao.secondCallInRequiredTransaction();
}
当忽略 RuntimeException 时,secondCallInRequiredTransaction 可能会导致错误。
如何解决这个问题,我看到了以下可能性:
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这篇文章是继上一篇文章“Observability:从零开始创建Java微服务并监控它(一)”的续篇。在上一篇文章中,我们讲述了如何创建一个Javaweb应用,并使用Filebeat来收集应用所生成的日志。在今天的文章中,我来详述如何收集应用的指标,使用APM来监控应用并监督web服务的在线情况。源码可以在地址 https://github.com/liu-xiao-guo/java_observability 进行下载。摄入指标指标被视为可以随时更改的时间点值。当前请求的数量可以改变任何毫秒。你可能有1000个请求的峰值,然后一切都回到一个请求。这也意味着这些指标可能不准确,你还想提取最小/
HashMap中为什么引入红黑树,而不是AVL树呢1.概述开始学习这个知识点之前我们需要知道,在JDK1.8以及之前,针对HashMap有什么不同。JDK1.7的时候,HashMap的底层实现是数组+链表JDK1.8的时候,HashMap的底层实现是数组+链表+红黑树我们要思考一个问题,为什么要从链表转为红黑树呢。首先先让我们了解下链表有什么不好???2.链表上述的截图其实就是链表的结构,我们来看下链表的增删改查的时间复杂度增:因为链表不是线性结构,所以每次添加的时候,只需要移动一个节点,所以可以理解为复杂度是N(1)删:算法时间复杂度跟增保持一致查:既然是非线性结构,所以查询某一个节点的时候
遍历文件夹我们通常是使用递归进行操作,这种方式比较简单,也比较容易理解。本文为大家介绍另一种不使用递归的方式,由于没有使用递归,只用到了循环和集合,所以效率更高一些!一、使用递归遍历文件夹整体思路1、使用File封装初始目录,2、打印这个目录3、获取这个目录下所有的子文件和子目录的数组。4、遍历这个数组,取出每个File对象4-1、如果File是否是一个文件,打印4-2、否则就是一个目录,递归调用代码实现publicclassSearchFile{publicstaticvoidmain(String[]args){//初始目录Filedir=newFile("d:/Dev");Datebeg
我基本上来自Java背景并且努力理解Ruby中的模运算。(5%3)(-5%3)(5%-3)(-5%-3)Java中的上述操作产生,2个-22个-2但在Ruby中,相同的表达式会产生21个-1-2.Ruby在逻辑上有多擅长这个?模块操作在Ruby中是如何实现的?如果将同一个操作定义为一个web服务,两个服务如何匹配逻辑。 最佳答案 在Java中,模运算的结果与被除数的符号相同。在Ruby中,它与除数的符号相同。remainder()在Ruby中与被除数的符号相同。您可能还想引用modulooperation.