Persistence API newbie question

Hello everybody!
I am new at J2EE development, so can you explain me some details. We're curently do J2EE application at work and using J2EE 1.5 features(EJB 3.0, Persistence etc..). I don't understand exactly what lies under annotations. Let's take Persistence API. All anotations and classes is in javax.persistence package. What is that package, where it come from? Is it located in container or where? In fact I would like to use Persistence API on sites managed by Apache Tomcat Server. Is it possible, what classes do I need? Another question is it is possible to use that API at Swing Applications, and what do I need to do this.
Please, explain me little of where all that stuff come from.
Thank you!

anotations and classes is in javax.persistence
package. What is that package, where it come from? Is
it located in container or where? Java Persistence API (JPA) is part of JavaEE 5 platform, and so is available in all JavaEE 5 compliant application servers. In JavaEE SDK 5, these classes are in lib/javaee.jar. JPA is also available as a standalone technology. There are several products that are implementing this technology, like Hibernate, TopLink, or OpenJPA.
The specification:
http://jcp.org/en/jsr/detail?id=220
Persistence Part in JavaEE 5 Tutorial (Part Four: Persistence )
http://java.sun.com/javaee/5/docs/tutorial/doc/
In fact I would
like to use Persistence API on sites managed by
Apache Tomcat Server. Is it possible, what classes do
I need? Another question is it is possible to use
that API at Swing Applications, and what do I need to
do this. They are all possible ways of using JPA. See JavaEE 5 Tutorial for more details. The newly released NetBeans 5.5 has nice support for developing and deploying JPA applications. NetBeans site has a lot of resources on this topic. For example:
http://www.netbeans.org/kb/55/persistence_ontomcat.html
http://www.netbeans.org/kb/articles/hibernate-javaee.html
-cheng

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- Pat

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J

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[INFO] org.jasig.cas:cas-server-webapp:war:3.2.1
[INFO] +- log4j:log4j:jar:1.2.15:runtime
[INFO] +- net.sf.ehcache:ehcache:jar:1.4.0-beta2:runtime
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[INFO] | \- backport-util-concurrent:backport-util-concurrent:jar:3.0:runtime
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[INFO] | +- org.springframework:spring-context-support:jar:2.5.1:compile
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[INFO] +- javax.servlet:jstl:jar:1.1.2:compile
[INFO] +- javax.servlet:servlet-api:jar:2.4:provided (scope not updated to compile)
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Can anuone help me on persistence API problem please?

I would like someone to explain me why when using persistence API
sometime i can insert data in database normally but later when i
have added more functionalities like ajax, and file upload i can
insert data in database using persistence API.
for instance, using this i was able in the begin of my development
but now i am not:
utx.begin();
inst.insert(name, email);
utx.commit();replace the code above by this below i can insert the data
at the same step of my project:
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            prepStmt.setString(2, email);So what's the problem? could anyone help me?Thanks!!
this explain either:http://forum.java.sun.com/thread.jspa?threadID=764824

Basically i totally not understand your question and i believe also nobody would understand what is your question. You mean your persistence APIs, but you didnt show how the APIs and just use it, i can say that, the only different of that JDBC and your 'persistence', is your JDBC isnt commit function(not include auto-commit). What i can see is that's all.
But the idea of usage DB conn API should be correct with the 3 steps,
Begin - Open connection
Query - insert/update/delete
Close - commit
catch - Rollback
Hopefully it helps.

Can anyone help me on persistence API problem?

I would like someone to explain me why when using persistence API
sometime i can insert data in database normally but later when i
have added more functionalities like ajax, and file upload i can
insert data in database using persistence API.
for instance, using this i was able in the begin of my development
but now i am not:
utx.begin();
inst.insert(name, email);
utx.commit();replace the code above by this below i can insert the data
at the same step of my project:
Class.forName("com.mysql.jdbc.jdbc2.optional.MysqlDataSource").newInstance();
            con = DriverManager.getConnection("jdbc:mysql://127.0.0.1/loja?user=marcos&password=131283");
            String selectStatement = "insert into cadastroswebradio values(?, ?)";
            PreparedStatement prepStmt = con.prepareStatement(selectStatement);
            prepStmt.setString(1, name);
            prepStmt.setString(2, email);So what's the problem? could anyone help me?Thanks!!
this explain either:http://forum.java.sun.com/thread.jspa?threadID=764824

Basically i totally not understand your question and i believe also nobody would understand what is your question. You mean your persistence APIs, but you didnt show how the APIs and just use it, i can say that, the only different of that JDBC and your 'persistence', is your JDBC isnt commit function(not include auto-commit). What i can see is that's all.
But the idea of usage DB conn API should be correct with the 3 steps,
Begin - Open connection
Query - insert/update/delete
Close - commit
catch - Rollback
Hopefully it helps.

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I am developing the overall architecture for an enterprise system. I intend to use the DAO pattern as the conceptual basis for all data access - this data will reside in a number of forms (e.g. RDBMS, flat file). In the specific case of the RDBMS, I intend to use JPA. My understanding of JPA is that it does/can support the DAO concept, but I'm struggling to get my head around how the two ideas (can be made to) relate to each other.
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