jbpm4.3不能查看流程图

错误代码为：

org.jbpm.api.JbpmException: couldn't extract bytes out of blob
	at org.jbpm.pvm.internal.lob.BlobStrategyBlob.get(BlobStrategyBlob.java:27)
	at org.jbpm.pvm.internal.lob.Lob.extractBytes(Lob.java:102)
	at org.jbpm.pvm.internal.repository.DeploymentImpl.getBytes(DeploymentImpl.java:182)
	at org.jbpm.pvm.internal.repository.RepositorySessionImpl.getBytes(RepositorySessionImpl.java:143)
	at org.jbpm.pvm.internal.cmd.GetResourceAsStreamCmd.execute(GetResourceAsStreamCmd.java:45)
	at org.jbpm.pvm.internal.cmd.GetResourceAsStreamCmd.execute(GetResourceAsStreamCmd.java:31)
	at org.jbpm.pvm.internal.svc.DefaultCommandService.execute(DefaultCommandService.java:42)
	at org.jbpm.pvm.internal.tx.SpringCommandCallback.doInTransaction(SpringCommandCallback.java:45)
	at org.springframework.transaction.support.TransactionTemplate.execute(TransactionTemplate.java:128)
	at org.jbpm.pvm.internal.tx.SpringTransactionInterceptor.execute(SpringTransactionInterceptor.java:55)
	at org.jbpm.pvm.internal.svc.EnvironmentInterceptor.executeInNewEnvironment(EnvironmentInterceptor.java:53)
	at org.jbpm.pvm.internal.svc.EnvironmentInterceptor.execute(EnvironmentInterceptor.java:40)
	at org.jbpm.pvm.internal.svc.RetryInterceptor.execute(RetryInterceptor.java:55)
	at org.jbpm.pvm.internal.repository.RepositoryServiceImpl.getResourceAsStream(RepositoryServiceImpl.java:81)
	at com.tepper.wfe.action.DrawGraphAction.drawActive(DrawGraphAction.java:90)
	at com.tepper.wfe.action.DrawGraphAction.execute(DrawGraphAction.java:50)
	at org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:419)
	at org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:224)
	at org.apache.struts.action.ActionServlet.process(ActionServlet.java:1196)
	at org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:414)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:617)
	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 com.tepper.common.SessionFilter.doFilter(SessionFilter.java:60)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
	at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:96)
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
	at org.springframework.orm.hibernate3.support.OpenSessionInViewFilter.doFilterInternal(OpenSessionInViewFilter.java:174)
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
	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:128)
	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:293)
	at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:849)
	at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:583)
	at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:454)
	at java.lang.Thread.run(Thread.java:619)

 

 

debug后找到这里：

public byte[] get(Lob lob) {
    if (lob.cachedBytes!=null) {
      return lob.cachedBytes;
    }
    
    java.sql.Blob sqlBlob = lob.blob;
    if (sqlBlob!=null) {
      try {
        return sqlBlob.getBytes(1, (int) sqlBlob.length());
      } catch (SQLException e) {
        throw new JbpmException("couldn't extract bytes out of blob", e);
      }
    } 
    return null;
  }

 

这里调用的是hibernate的代码，然后使用LOB定位器，如果是新的部署，是会返回byte[]！

 

从现有的部署中我们来开启一个流程，他的调用是这样的：

log.trace("loading deployment "+deploymentId+" from db");
 DeploymentImpl deployment = (DeploymentImpl) session.load(DeploymentImpl.class, Long.parseLong(deploymentId));
 deployerManager.deploy(deployment);
 object = repositoryCache.get(deploymentId, objectName);
 if (object==null) {
 throw new JbpmException("deployment "+deploymentId+" doesn't contain object "+objectName);
 }

 

这段代码是从数据库加载，而它不会加载BLOB数据 和用LOB定位器代替；然后， deployerManager.deploy(deployment); LOB定位器将调用来获取数据， 由于ResultSet已经关闭，异常发生！

解决方法是：

把<prop key="hibernate.connection.release_mode">auto</prop>此属性去掉！

hibernate.connection.release_mode的用途是：指定Hibernate在何时释放JDBC连接. 默认情况下,直到Session被显式关闭或被断开连接时,才会释放JDBC连接. 对于应用程序服务器的JTA数据源, 你应当使用after_statement, 这样在每次JDBC调用后，都会主动的释放连接. 对于非JTA的连接, 使用after_transaction在每个事务结束时释放连接是合理的. auto将为JTA和CMT事务策略选择after_statement, 为JDBC事务策略选择after_transaction. 取值 on_close | after_transaction | after_statement | auto

 

评论

2 楼 windywindy 2012-10-08  

fatter 写道

lz用的是什么数据库？我用的db2上报这样的错误，前提是我没有添加

<prop key="hibernate.connection.release_mode">auto</prop>

这个属性，但是还是报这样的错误

用的是oracle

1 楼 fatter 2012-08-06  

lz用的是什么数据库？我用的db2上报这样的错误，前提是我没有添加

<prop key="hibernate.connection.release_mode">auto</prop>

这个属性，但是还是报这样的错误