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POJDO basics: List or array won't retrieve or return with GWT RPC
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  1. POJDO basics: List or array won't retrieve or return with GWT RPC
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    copied!<p>I've been using Objectify up till now, but now I have to deal with some code using JDO. I'm having problems with basic stuff that is easy with Objectify, specifically: if an object has either a List or an array as a member, I can't get that to persist.</p> <p>I have a class FileInfoBatch (code indents lost here, don't know why) containing a List of FileInfo:</p> <pre><code>@PersistenceCapable public class FileInfoBatch implements Serializable{ private static final long serialVersionUID = 1L; @PrimaryKey @Persistent(valueStrategy = IdGeneratorStrategy.IDENTITY) private Key key; @Persistent private List&lt;FileInfo&gt; fileInfoList; @Persistent private String savedByUserEmail; public FileInfoBatch(){ fileInfoList=new ArrayList&lt;FileInfo&gt;(); } </code></pre> <p>Then I send a FileInfoBatch (called fib) containing just 1 FileInfo in the List, to my RPC impl class &amp; persist it, then query for it straight away for a test (in debugger)</p> <pre><code> PersistenceManager pm = PMF.get().getPersistenceManager(); pm.makePersistent(fib); Query query = pm.newQuery(FileInfoBatch.class, "savedByUserEmail == '"+ userEmail + "'"); List&lt;FileInfoBatch&gt; savedList = (List&lt;FileInfoBatch&gt;) query.execute(); FileInfoBatch persisted=savedList.get(0); </code></pre> <p>The persisted FileInfoBatch comes back with an empty FileInfo list. If I use a single Fileinfo member, this persists ok.</p> <p>I find no such basic problem reported on this site &amp; I've looked at the docs: <a href="https://developers.google.com/appengine/docs/java/datastore/jdo/dataclasses" rel="nofollow">https://developers.google.com/appengine/docs/java/datastore/jdo/dataclasses</a></p> <p>Does such a simple storage task require huge complexity? If so I will go back to using Objectify.</p>
 

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