异常：查询结果集不可修改 [英] Exception: Query result sets are not modifiable

问题描述

  PersistenceManager pm = PMF.get（）。 getPersistenceManager（）; 
 
 try {
 pm.currentTransaction（）。begin（）; 
 
 //取消所有当前域
查询q = pm.newQuery（CampaignStore.class，domain ==+ domain +'）; 
 Collection result =（Collection）q.execute（）; 
 
 CampaignStore toBeEdited = null; 
迭代器iter = result.iterator（）; 
 while（iter.hasNext（））{
 toBeEdited =（CampaignStore）iter.next（）; 
 toBeEdited.setActive（false）; 
} 
 result.clear（）; 
 
 //设置新的活动
 q = pm.newQuery（CampaignStore.class，id ==+ id）; 
 result =（Collection）q.execute（）; 
 toBeEdited =（CampaignStore）result.iterator（）。next（）; 
 if（toBeEdited == null）{
 LOG.log（Level.WARNING，setActiveCampaign：无法找到广告系列ID+ id +'）; 
 pm.currentTransaction（）。rollback（）; 
返回; 
} 
 toBeEdited.setActive（true）; 
 
 pm.currentTransaction（）。commit（）; 
 LOG.log（Level.INFO，setActiveCampaign：Active Campaign ID now now'+ id +'）; 
} 
 catch（异常e）{
 pm.currentTransaction（）。rollback（）; 
 LOG.log（Level.WARNING，setActiveCampaign：Exception：+ e.getMessage（））; 
} finally {
 pm.close（）; 
} 
  

不幸的是我得到一个查询结果集不可修改的异常。 p>

我确定它来自第一个查询与迭代，因为第二个单独的工作。

任何想法我需要改变以使查询结果可修改？

解决方案

我删除了try / catch块，并得到一个更详细的消息java.lang.IllegalArgumentException：不能在单个事务中的多个实体组上操作，这有助于我解决我的问题。

我需要关闭交易：

  pmfInstance.setNontransactionalRead（true）; 
 pmfInstance.setNontransactionalWrite（true）; 
  

我不需要代码是交易安全的。

在此可以找到更多信息：
http://groups.google.com/group/google-appengine-java/browse_thread/thread/04f35b443c15d531

I'm trying to write to a JDO store using this code:

    PersistenceManager pm = PMF.get().getPersistenceManager();

    try {
        pm.currentTransaction().begin();

        // deactivate all for current domain
        Query q = pm.newQuery(CampaignStore.class, "domain == '" + domain +"'");
        Collection result = (Collection) q.execute();

        CampaignStore toBeEdited = null;
        Iterator iter = result.iterator();
        while (iter.hasNext()) {
            toBeEdited = (CampaignStore) iter.next();
            toBeEdited.setActive(false);
        }
        result.clear();

        // set new one active
        q = pm.newQuery(CampaignStore.class, "id == " + id);
        result = (Collection) q.execute();
        toBeEdited = (CampaignStore) result.iterator().next();
        if (toBeEdited == null) {
            LOG.log(Level.WARNING, "setActiveCampaign: Unable to find Campaign ID '"+ id +"'");
            pm.currentTransaction().rollback();
            return;
        }           
        toBeEdited.setActive(true);

        pm.currentTransaction().commit();
        LOG.log(Level.INFO, "setActiveCampaign: Active Campaign ID is now '"+ id +"'");
    }
    catch (Exception e) {
        pm.currentTransaction().rollback();
        LOG.log(Level.WARNING, "setActiveCampaign: Exception: "+ e.getMessage());
    } finally {
        pm.close();
    }

Unfortunately I get an "Query result sets are not modifiable" exception.

I'm quite sure it comes from the first query with the iteration, cause the second one alone will work.

Any ideas what I need to change to make the query result modifiable?

解决方案

I removed the try/catch block and got a more detailed message "java.lang.IllegalArgumentException: can't operate on multiple entity groups in a single transaction.", which helped me solve my problem.

I needed to turn off transactions:

pmfInstance.setNontransactionalRead(true);
pmfInstance.setNontransactionalWrite(true);

I don't need the code to be transaction safe.

Here you can find more information: http://groups.google.com/group/google-appengine-java/browse_thread/thread/04f35b443c15d531

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