Newbie question on Java Persistence API - Entity Beans

Hi All,
I am basically new to Entities and the Java Persistence API. My question is, when using a container managed EntityManager, do I have to manually tidy-up any resources? Say for example, do I have to explicitly close the database connection (if ever I have that ability)? Invoke close() on EntityManager?
- Pat

You don't have to. That's what they mean by container managed. The container does it for you.
In fact you will get an IllegalStateException if you call close on a container-managed EntityManager.

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http://java.sun.com/javaee/overview/faq/persistence.jsp

Java Persistence API and creation of databases

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Thanks, duffymo, that makes sense. However ... having read through numerous threads in which you voice your opinion of the DAO World According to Sun, I'd be interested to know your thoughts on the following ...
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Hi,
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@Id
@GeneratedValue( @GeneratedValue(strategy= GenerationType.TABLE, generator="SOMENAME")
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returrn this.id;
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Java persistence API

Hi! I am trying to learn to use the http://www.devx.com/Java/Article/33650/ api manually, i tried using netbeans 6.0 for it but i'm not very sure what it does so i am going to try it manually now. I've read these 2 articles by Antonio Goncalves
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Hi! I am trying to learn to use the http://www.devx.com/Java/Article/33650/ api manually, i tried using netbeans 6.0 for it but i'm not very sure what it does so i am going to try it manually now. I've read these 2 articles by Antonio Goncalves
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Anybody can help? Also if you know any kind of tutorial for the persistence api if you could point me towards there it would be nice.
And finally sorry if i have misplaced this post, I couldn't find a better place.
Thanks, Joaquin

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Newbie question: tapping native OS APIs through java?

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registry key
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stop/start a windows service
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perhaps log something to the eventlog
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I could write extend Java with C functions, but thats not practical each time you want to touch the OS
Eeh? How else do you expect it to work?
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You said:
"If we stay with the hibernate tutorial that we have "Animals" and "Pavillion" entities.
How would one efficiently design a "Table" component that shows a list of all Animals and their Pavillions.
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Hello Java Programmers.
Question to Object handling with Query results and evaluation.
Example:
one table with 3 Columns
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Column 2 = language name
Column 3 = language long name
data in database:
C1 = 1
C2 = "ger"
C3 = "german"
read the data from database with EntityManagerFactory and EntityManager
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Search short code for example!
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// warnings -> List is a raw type. References to generic type List<E> should be parameterized
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// = [1,ger,german]I do not want to use
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for one elements from [1,ger,german]
final to
1
ger
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no answer? = is an answer !
the normal solution would be for example.
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Best greetings

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Hi libin_hailang
The last two packages are not part of the api.
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hi,
I used to be a .net programmer for a few years, and am have done web services in .net.... (using IIS, of course)
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I think I can answer your Q1
Apache is very good at serving simple HTML pages
Tomcat is capable of serving active content
So the two complement each other
Or that's how I understand it.
Steaker

JPA, java persistence Api, troubleshooting

Hi everybody.
I have a small but boring problem.
I am new at Netbeans and Java Sdk.
I downloaded Netbeans 6.1 and SDK 6.
I tried to exercise "simple database application" in the netbeans web page.
A error encountered that:
24.Tem.2008 10:04:16 org.jdesktop.application.Application$1 run
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oracle.toplink.essentials.ejb.cmp3.EntityManagerFactoryProvider
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at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:154)
at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:83)
I can't fix this. anybody know the solution??
hanks, good work.

Assalamu Alaikum,
Check in persistence.xml whether persistence-unit is same in Persistence.createEntityManagerFactory*("simpleAppPU")* or not. It should be same.
persistence.xml is like as follows:
<?xml version="1.0" encoding="UTF-8"?>
<persistence version="1.0" xmlns="http://java.sun.com/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_1_0.xsd">
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Newbie question about Java Studio Creator 2.

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Can anyone advise me on my question?
Thank you.

Newbie question on Java Persistence API - Entity Beans

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