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copied!<p>I could not get this to work for multiple reasons:</p> <ol> <li>I could not get the data once persisted to the mongoDB to load back into the object, the object would always just be null.</li> <li>After issue #1, I added a private list that would populate my MorphiaList on lookup to get around it. But after getting the ids into the MorphiaList, I could not figure out how to do a lookup on the specific collections. Especially when you consider I use inheritance so I have some heterogeneous collections.</li> </ol> <p>My Solution: For every List of references I rewrote this: </p> <pre><code>@Reference public List<Season> seasons; </code></pre> <p>To this:</p> <pre><code>@Transient public List<Season> seasons; private List<ObjectId> _seasons = new ArrayList(); @Transient private List<Season> pSeasons; public List<Season> getSeasons() { if(pSeasons==null) { if(_seasons.size()!=0) pSeasons = Season.find().<Season>field("_id").in(_seasons).asList(); else pSeasons = new ArrayList(); } return pSeasons; } </code></pre> <p>I also had to add a <strong>@PrePersist</strong> method to check for list access:</p> <pre><code>@PrePersist void beforeSave() { if(pSeasons!=null) { _seasons.clear(); for(Season s: pSeasons) { _seasons.add((ObjectId)s.getId()); } } } </code></pre> <p>This <strong>beforeSave()</strong> will have to expand for every extra List of refs you have in your code. Moral of the story: </p> <p><em>If you're using Play's morphia module, don't use the @Reference notation.</em></p>

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