Question

I’ve a web project that includes java class with JDO annotation. My database is MongoDB. I use datanucleus in my project. To persist my java object in my database, I use this code :

    ListAcc list = new ListAcc();
    list.name = "created";
    pm.makePersistent(list);

Then, I retrieve my document with this code :

    ListAcc l = pm.getObjectById(ListAcc.class,"507675823004b91181edc746");

Until that point, everything is working. Now, I’d like to update my document. For doing that, I use this code :

    Transaction tx = pm.currentTransaction();
    tx.begin();
    try {
      ListAcc l = pm.getObjectById(ListAcc.class,"507675823004b91181edc746");
      l.name = "changing";
      tx.commit();
    } catch(Exception e) {
      tx.rollback();
    }

However, this operation doesn’t update my document.

Could you help me to update my document?

Thanks a lot

Answer 1

You mean you update a PUBLIC field on that class?
Firstly its bad programming practice to use public fields, and secondly if you wish to do that in a persistence context you have to annotate the class updating these public fields as @PersistenceAware (or just use setter methods on the class). All of that is in the DN docs