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General J2EE: Options of Entity beans

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  1. Options of Entity beans (7 messages)

    I have to model an enterprise application. If you follow OOAD and come with an class diagram, where some of the class needs to be presisted and retrieved. If I don't hv to go for Entity beans, what are other options available for me.
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  2. Options of Entity beans[ Go to top ]

    hibernate -> http://hibernate.sf.net

    JDO not sure of any websites
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  3. Options of Entity beans[ Go to top ]

    Is JDO supported in major Application Servers. My solution has to work on Websphere application server. Is Hibernate also works on Websphere Application Server connection to a DB2 database
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  4. Options of Entity beans[ Go to top ]

    Hibernate is very promising. It does support DB2 and it works in any J2EE and non-J2EE environment. Checkout http://www.hibernate.org. You might be interested in reading the features section there.
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  5. Options of Entity beans[ Go to top ]

    Please, AVOID entity beans on WebSphere, at least if you want to be able to build your project in less than one hour.
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  6. Options of Entity beans[ Go to top ]

    Why that so? Can you please share your exp. on Webshpere. We are planning to use CMP with Websphere 4.03
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  7. Options of Entity beans[ Go to top ]

    The catch with CMPs is that you need to generate server-specific descriptors that do the O-R mapping (property X of EJB = field Y of table). In every app server these mappings are written in a few readable XML files, wich you may even write by hand from scratch.

    In WAS these descriptors are **many**, and all of them are simply unreadable. Only God knows why, because no other product screwed it so badly. Writing them from scratch (even the simplest ones) can't be done. Your options are:

    1. Use WSAD (and stay in WAS forever);
    2. Use an advanced IDE that converts CMP descriptors between servers at any time (as far as I know only JBuilder can do it);
    3. Use XDoclet, but I don't know if it works well with WAS. I wouldn't be surprised if there were limitations with WAS here (since WAS CMP descriptors are so incredibly messed up).

    As weird as it seems, bringing CMP into your project adds some risk to portability - converting your CMP descriptors into another platform can be quite difficult. Of course, if portability isn't an issue you can stick with WSAD.

    Now, buy LOTS of RAM to your workstation. The ejbdeploy tool is VERY, VERY heavy-weight. It takes AGES to process each EBJ (specially CMPs), ant its error messages are usually inacurate (to say the least). It is a nightmare, believe me.
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  8. Options of Entity beans[ Go to top ]

    How does Hibernate compare with JDO?
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