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From wang yu <wangy...@gmail.com>
Subject Re: How to release db connection into pool?
Date Fri, 22 Jan 2010 03:35:34 GMT
Craig,
 I have tested it. It's cool!
The db connection will be returned into pool and I can reuse the
JPAEntityManager!
Thanks again.

Regards,
Yu Wang

On Fri, Jan 22, 2010 at 9:57 AM, wang yu <wangyumi@gmail.com> wrote:
> Craig:
> Thank you for your quick response.
> If I close it, the connection will be returned into pool or just destroyed?
>
> Regards,
> Yu Wang
>
> On Thu, Jan 21, 2010 at 8:56 PM, Craig L Russell <Craig.Russell@sun.com> wrote:
>> Hi Yu Wang,
>>
>> You need to tell OpenJPA that you're not using the Connection any more by
>> calling close(). See this Example 4.4 in the user's manual:
>>
>> import java.sql.*;
>>  import org.apache.openjpa.persistence.*;
>>  ... OpenJPAEntityManager kem = OpenJPAPersistence.cast(em);
>> Connection conn = (Connection) kem.getConnection();
>>  // do JDBC stuff
>>  conn.close();
>>
>> Regards,
>>
>> Craig
>> On Jan 21, 2010, at 1:26 AM, wang yu wrote:
>>
>>> Gurus:
>>> I use OpenJPA 1.2.1 and dbcp:
>>>                        <property name="openjpa.ConnectionDriverName"
>>>
>>>  value="org.apache.commons.dbcp.BasicDataSource" />
>>>                        <property name="openjpa.ConnectionProperties"
>>>
>>>  value="driverClassName=oracle.jdbc.driver.OracleDriver,
>>> url=jdbc:oracle:thin:@localhost:1521:orcl, username=XXXX,
>>> password=XXX, maxActive=8, maxWait=10000, poolPreparedStatements=true"
>>> />
>>>
>>> And I found the connection pool worked perfect for JPA query. But if I
>>> use JDBC query like following:
>>>                OpenJPAEntityManager open_manager = OpenJPAPersistence
>>>                                        .cast(entitiManager);
>>>                Connection conn = (Connection)
>>> open_manager.getConnection();
>>>                java.sql.PreparedStatement PrepStmt = null;
>>>                java.sql.ResultSet sqlResults = null;
>>>                try {
>>>                        PrepStmt = connection
>>>                                        .prepareStatement("select
* from
>>> tsam.MON_BRIDGE");
>>>                        sqlResults = PrepStmt.executeQuery();
>>>                } catch (SQLException e) {
>>>                        log.error(e.getMessage());
>>>                } finally {
>>>                        try {
>>>                                if (sqlResults != null)
>>>                                        sqlResults.close();
>>>                                if (PrepStmt != null)
>>>                                        PrepStmt.close();
>>>                        } catch (SQLException e) {
>>>
>>>                        }
>>>                }
>>>
>>> The connection cannot be put into pool and the result is out of db
>>> connection.
>>> How should I do?  Should I use createNativeQuery(String sql, Class
>>> resultClass)  to query with native sql?
>>>
>>>
>>> Regards,
>>> Yu Wang
>>
>> Craig L Russell
>> Architect, Sun Java Enterprise System http://db.apache.org/jdo
>> 408 276-5638 mailto:Craig.Russell@sun.com
>> P.S. A good JDO? O, Gasp!
>>
>>
>

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