Java Persistence API and creation of databases

Hi All
I have designed a small address book application which uses a database to store the information. I have used the new Java Persistence API to take care of my transactions and querrys with the database. This works great for one set database which is generated the first time the application runs and is used all the time.
However I would like to make it so that the user can create a new address book (database) with a different name, I am not sure how I would do this using the Java Persistence API. I know the persistence.xml file must be placed in the META-INF directory of the source, so how would I be able manipulate the file or could I place the file somewhere else.
David

I am using the Derby database. I can create a database by passing the create command when I create the entity Manager like so:
Connection c = DriverManager.getConnection("jdbc:derby:AddressBook;create=true", "app", "app");My problem is that as I understand it the persistence.xml file must know the name of the database. Unless there is another way of setting this. The line in the persistence file I am referring to is:
<property name="toplink.jdbc.url" value="jdbc:derby:AddressBook"/>I wonder if I can progamatically set this value so that I have a default database in the persistence.xml and others can then create there own.
David

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@Id
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import java.io.*;
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Hi all ,
I am posting a working example of Passing Array of java objects to and from oracle database . I have struggled a lot to get it working and since finally its working , postinmg it here so that it coudl be helpful to the rest of the folks.
First thinsg first
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import java.io.*;
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create or replace
procedure give_me_an_array( p_array in person_tab,p_arrayout out person_tab)
as
l_person_id Number;
l_person_name Varchar2(200);
l_person person_t;
l_p_arrayout person_tab;
errm Varchar2(2000);
begin
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for i in 1 .. p_array.count
loop
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     l_person.person_id := l_person_id + 5;
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p_arrayout := l_p_arrayout;
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for i in 1 .. p_arrayout.count
loop
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commit;
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end;
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import java.util.Date;
import java.io.*;
import java.sql.*;
import oracle.sql.*;
import oracle.jdbc.driver.*;
import java.text.DateFormat;
import java.text.ParseException;
import java.text.SimpleDateFormat;
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ArrayDemo a = new ArrayDemo();
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pn1.person_id = 1;
pn1.person_name = "SunilKumar";
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pn2.person_id = 2;
pn2.person_name = "Superb";
Person pn3 = new Person();
pn3.person_id = 31;
pn3.person_name = "Outstanding";
Person[] P_arr = {pn1, pn2, pn3};
Person[] P_arr_out = new Person[3];
ArrayDescriptor descriptor =
ArrayDescriptor.createDescriptor( "PERSON_TAB", conn );
ARRAY array_to_pass =
new ARRAY( descriptor, conn, P_arr);
OracleCallableStatement ps =
(OracleCallableStatement )conn.prepareCall
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Object[] personDetails = (Object[]) returnArray.getArray();
Person person_record = new Person();
for (int i = 0; i < personDetails.length; i++) {
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                         tfc.passArray();
     catch(Exception e) {
                    e.printStackTrace();
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     try
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                         "username", "password");
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                    System.out.println("IN EXCEPTION BLOCK ");
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and thats it. you are done.
Hope it atleast helps people to get started. Comments are appreciated. I can be reached at ([email protected]) or [email protected]
Thanks
Sunil.s

Hi Sunil,
I've a similar situation where I'm trying to insert Java objects in db using bulk insert. My issue is with performance for which I've created a new thread.
http://forum.java.sun.com/thread.jspa?threadID=5270260&tstart=30
I ran into your code and looked into it. You've used the Person object array and directly passing it to the oracle.sql.ARRAY constructor. Just curios if this works, cos my understanding is that you need to create a oracle.sql.STRUCT out of ur java object collection and pass it to the ARRAY constructor. I tried ur way but got this runtime exception.
java.sql.SQLException: Fail to convert to internal representation: JavaBulkInsertNew$Option@10bbf9e
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                    at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:146)
                    at oracle.jdbc.oracore.OracleTypeADT.toDatum(OracleTypeADT.java:239)
                    at oracle.jdbc.oracore.OracleTypeADT.toDatumArray(OracleTypeADT.java:274)
                    at oracle.jdbc.oracore.OracleTypeUPT.toDatumArray(OracleTypeUPT.java:115)
                    at oracle.sql.ArrayDescriptor.toOracleArray(ArrayDescriptor.java:1314)
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                    at JavaBulkInsertNew.main(JavaBulkInsertNew.java:76)
Here's a code snippet I used :
Object optionVal[] =   {optionArr[0]};   // optionArr[0] is an Option object which has three properties
oracle.sql.ArrayDescriptor empArrayDescriptor = oracle.sql.ArrayDescriptor.createDescriptor("TT_EMP_TEST",conn);
ARRAY empArray = new ARRAY(empArrayDescriptor,conn,optionVal);If you visit my thread, u'll see that I'm using STRUCT and then pass it to the ARRAY constructor, which works well, except for the performance issue.
I'll appreciate if you can provide some information.
Regards,
Shamik

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Java Persistence API and creation of databases

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