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Questions tagged [jdo]

Java Data Objects (JDO) is a standard way to access persistent data in databases, using plain old Java objects (POJO) to represent persistent data. It is designed to be datastore-agnostic, allowing persistence to, potentially, any type of datastore

Java Data Objects (JDO) is a Java specification for accessing, persisting, and managing data between Java objects / classes and a datastore. JDO 1.0 (2002) defined the basic API, JDO 2.0 (2006) included a comprehensive definition of ORM as well as other enhancements, and JDO 3.0 (2009) added on annotations, as well as APIs for fetch groups and metadata. It is the most complete specification for Java persistence around

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Unsure if I understand TransactionAwarePersistenceManagerFactoryProxy

I am trying to use the org.springframework.orm.jdo.TransactionAwarePersistenceManagerFactoryProxy in my Spring project, but I am not sure how to use it or whether it's exactly what I am looking for. I realize it can help make my DAOs work with a…
megazord
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Hibernate vs JPA vs JDO - pros and cons of each?

I'm familiar with ORM as a concept, and I've even used nHibernate several years ago for a .NET project; however, I haven't kept up with the topic of ORM in Java and haven't had a chance to use any of these tools. But, now I may have the chance to…
matt b
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JDO vs JPA for Java on Google App Engine

I want to develop my project on Google App Engine with Struts2. For the database I have two options JPA and JDO. Will you guys please suggest me on it? Both are new for me and I need to learn them. So I will be focused on one after your…
Tahir Akram
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Java AppEngine: JDO or JPA, How to choose?

Pros and Cons of choosing JDO or JPA for a Grails Application that will run on Google AppEngine
zotherstupidguy
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Why put a DAO layer over a persistence layer (like JDO or Hibernate)

Data Access Objects (DAOs) are a common design pattern, and recommended by Sun. But the earliest examples of Java DAOs interacted directly with relational databases -- they were, in essence, doing object-relational mapping (ORM). Nowadays, I see…
Todd Owen
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Committed JDO writes do not apply on local GAE HRD, or possibly reused transaction

I'm using JDO 2.3 on app engine. I was using the Master/Slave datastore for local testing and recently switched over to using the HRD datastore for local testing, and parts of my app are breaking (which is to be expected). One part of the app…
eeeeaaii
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Sending persisted JDO instances over GWT-RPC

I've just started learning Google Web Toolkit and finished writing the Stock Watcher tutorial app. Is my thinking correct that if one wants to persist a business object (like a Stock) using JDO and send it back and forth to/from the client over RPC…
CodeAndCats
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Difference between JPA and JDO?

want to develop my project on Google App Engine .I want to use google big table as database. For the database I have two options JPA and JDO. Will you guys please suggest me on it? Both are new for me and I need to learn them. So I will be focused…
user246160
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High Level Java Client selection for Apache Cassandra

There are four high level APIs to access Cassandra and I do not have time to try them all. So I hoped to find somebody who could help me to choose the proper one. I'll try to write down my findings about…
andreas
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Datanucleus Programmatic API Class Enhancement

I'm using Eclipse 3.7 (OSGI), and i can do the manual Enhancement (with the Datanucleus Eclipse Plugin & datanucleus-enhancer-2.1.0-release imported as plugin dependency) I'm trying now to use the API Class Enhancement:…
marcolopes
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How can I reduce Google App Engine datastore latency?

Through appstats, I can see that my datastore queries are taking about 125ms (api and cpu combined), but often there are long latencies (e.g. upto 12000ms) before the queries are executed. I can see that my latency from the datastore is not related…
chow
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How to solve validation error on xsi:noNamespaceSchemaLocation in jdoconfig.xml

Since I updated today to GAE 1.7.2.1, I'm having validation errors in eclipse in all my jdoconfig.xml files. I have the default jdoconfig.xml content : [...]
mamuso
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Why Objectify instead of JDO?

I am approaching to Gwt + Gae world. My essential need is to send over the Gwt-Rpc wire my Entity classes, without duplicating them into DTOs. Objectify promise to do that pretty well. It claims it will hide all the "Jdo complexity". I never worked…
Fabio B.
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Whats the difference between JPA and JDO specifications?

I have been using Hibernate ORM, which is an implementation of the JPA specification to manage relational data. I have also heard of the JDO specification that supposed to do the same (manage relational data). What are the fundamental differences…
n002213f
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Why am I getting errors in jdoconfig.xml?

Eclipse marker tab shows some xml problem. This occurred when I checked dynamic web module in the Project Facets. This is my project hierarchy : jdconfig.xml (automatically generated) :
Suhail Gupta
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