persistence

Let's say I have something like this: d = { "abc" : [1, 2, 3], "qwerty" : [4,5,6] } What's the easiest way to progammatically get that into a file that I can load from python later? Can I somehow save it as python source (from within a python script, not manually!), then import it later? Or should I use JSON or something? Use the pickle module. import pickle d = { "abc" : [1, 2, 3], "qwerty" : [4,5,6] } afile = open(r'C:\d.pkl', 'wb') pickle.dump(d, afile) afile.close() #reload object from file file2 = open(r'C:\d.pkl', 'rb') new_d = pickle.load(file2) file2.close() #print dictionary object

How can I generate JPA2 compliant @Entity from existing Databases?. I found this: Question Still its not clear if JBoss will generate compliant JPA2 and also I would like to know if there is a vendor independent way to do this. You can use a plugin like Eclipse Dali to do the trick for you. You can refer to the documentation, section 3.11 Generating Entities from Tables . I do not know of any specific vendor independent tool to do this, though. Try using OPENJPA Reverse mapping tools. They offer lot more facility and are easy to configure. This example would clarify. If you are using maven as

persistence.xml looks like this: <persistence-unit name="testPU" transaction-type="RESOURCE_LOCAL"> <provider>org.hibernate.ejb.HibernatePersistence</provider> <non-jta-data-source>jdbc/test</non-jta-data-source> <jar-file>../../lib/app-services-1.0.jar</jar-file> <exclude-unlisted-classes>false</exclude-unlisted-classes> </persistence-unit> It is a web project, so the deployment unit is a war file. The jar file I tried to refer is in WEB-INF/lib/ folder , persistence.xml is in WEB-INF/classes/META-INF folder. When being deployed, it simply tells me "WARNING: Unable to find file (ignored):

We have loads of apps where we fetch data from remote web services as JSON and then use a parser to translate that into a Core-Data model. For one of our apps, I'm thinking we should do something different. This app has read-only data , which is volatile and therefore not cached locally for very long . The JSON is deeply hierarchal with tons of nested "objects" . Documents usually contain no more than 20 top level items, but could be up to 100K. I don't think I want to create a Core Data model with 100's of entities, and then use a mapper to import the JSON into it. It's seems like such a song

In a Java EE 6 application where I'm using .ear packaging, I'd like to create a persistence unit that can be accessed from components in different .jar files. However, I'm not sure how to define this persistence unit. With the @PersistenceContext annotation the lookup only succeeds if the name matches a persistence unit defined in the local persistence.xml file. Is it possible to refer to external persistence units? Pascal Thivent Here are the relevant sections of the JPA 2.0 specification: 8.2 Persistence Unit Packaging ... A persistence unit is defined by a persistence.xml file. The jar file

I'm facing what I think is a simple problem with Hibernate, but can't solve it (Hibernate forums being unreachable certainly doesn't help). I have a simple class I'd like to persist, but keep getting: SEVERE: Field 'id' doesn't have a default value Exception in thread "main" org.hibernate.exception.GenericJDBCException: could not insert: [hibtest.model.Mensagem] at org.hibernate.exception.SQLStateConverter.handledNonSpecificException(SQLStateConverter.java:103) at org.hibernate.exception.SQLStateConverter.convert(SQLStateConverter.java:91) [ a bunch more ] Caused by: java.sql.SQLException:

Is it a correct practice to use JavaFX beans properties in the model classes? I wonder if it is a good practice to use properties in model classes to be able to bind them easier with the view components. I'm not worried about the availability of those libraries in future because my program will be run on JRE8 or later but the nature of using the JavaFX libraries in the model classes make me skeptical and I'm worried about current and future incompabilities specially because I want to use Hibernate to persist those attributes. Note: I use a pure JavaFX environment and I will never need Swing