Closing a result set you left open!, MySQL

[marcusdidiusfalco]

Hi, I am just beginning to experiment with JPA.
I have jboss-4.2.1.GA and MySQL 5.0.45 community installed and I am using mysql-connector-java-5.0.6 as JDBC driver.

With

@Stateless
public class TestBean implements TestRemote {

 @PersistenceContext(unitName="ejbbuch")
 EntityManager entityManager;


 @TransactionAttribute(TransactionAttributeType.REQUIRED)
 public Product addProduct(Product product) {
 entityManager.persist(product);
 return product;
 }

 .....
---------------------------------------------------------------------------------
@Entity
public class Product implements Serializable {

 @Id
 @GeneratedValue(strategy=GenerationType.IDENTITY)
 private long id;
 ........

-------------------------------------------------------------------------------
<?xml version="1.0" encoding="UTF-8"?>
<persistence>
 <persistence-unit name="ejbbuch">
 <jta-data-source>java:/MySqlDS</jta-data-source>
 </persistence-unit>
</persistence>

---------------------------------------------------------------------------------
<datasources>
 <local-tx-datasource>
 <jndi-name>MySqlDS</jndi-name>
 <connection-url>jdbc:mysql://localhost:3306/jbossdb</connection-url>
 <driver-class>com.mysql.jdbc.Driver</driver-class>
 <user-name>root</user-name>
 <password>ritak1</password>
 <min-pool-size>6</min-pool-size>
 <max-pool-size>20</max-pool-size>
 <blocking-timeout-millis>5000</blocking-timeout-millis>
 <idle-timeout-minutes>0</idle-timeout-minutes>
 <exception-sorter-class-name>org.jboss.resource.adapter.jdbc.vendor.MySQLExceptionSorter</exception-sorter-class-name>
 <!-- should only be used on drivers after 3.22.1 with "ping" support
 -->
 <valid-connection-checker-class-name>org.jboss.resource.adapter.jdbc.vendor.MySQLValidConnectionChecker</valid-connection-checker-class-name>
 <new-connection-sql>SELECT count(*) FROM product</new-connection-sql>
 <check-valid-connection-sql>SELECT count(*) FROM product</check-valid-connection-sql>
 <share-prepared-statements>true</share-prepared-statements>
 <prepared-statement-cache-size>10</prepared-statement-cache-size>
 <track-statements>true</track-statements>
 <metadata>
 <type-mapping>mySQL</type-mapping>
 </metadata>
 </local-tx-datasource>
</datasources>

I get the following exceptions in the log file:

2007-09-28 13:41:04,265 WARN [org.jboss.resource.adapter.jdbc.WrappedConnection] Closing a result set you left open! Please close it yourself.
java.lang.Throwable: STACKTRACE
 at org.jboss.resource.adapter.jdbc.WrappedStatement.registerResultSet(WrappedStatement.java:617)
 at org.jboss.resource.adapter.jdbc.WrappedStatement.getGeneratedKeys(WrappedStatement.java:533)
 at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
 at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)

When I switch back to the DefaultDS (HSQL) this disappears.

Otherwise the code works as expected with the MySQL database. But of course in a production environment you would not want to force JBoss to handle unclosed statements or resultsets.

Is this some problem with the JDBC driver or do I have some bug in my code?

Thanks,

Hans

[bgmf]

Hello Marcus,

unfortunately I cannot help you with your Problem, but maybe you can give me an Advise how to bound MySQL.

I tried to do a working mysqlds, but it doesn't work...

What have you done? I would be glad to have your problems :-/

Yours,
BGMF

[marcusdidiusfalco]

Hi BGMF,

1. Download a JDBC driver from the MySQL site.
http://dev.mysql.com/downloads/connector/j/5.0.html
and put it into the lib or deploy directory of your server configuration.
2. Copy <JBoss_Home>\docs\examples\jca\mysql-ds.xml to your deploy directory and adjust it. Basically you simply have to adjust the connection url, driver-class, user-name and password.
If user-name or password are wrong you might get a funny exception about the wrong Hibernate dialect which can be confusing.
3. The jndi-name of your datasource must be referenced in your persistence.xml file like java:/
Basically all the code to make this work (except for the problem I have) is listed in my example.

Hope that helps, otherwise what exactly is your problem?

Greetings,

Hans

[bgmf]

Hi Marcus!

The funny thing is: I've done excactly all these things.
Maybe the reason is, because I've done the jdbc-lib also in my eclipse project... Maybe jboss is confused because of duplicate drivers...

But thank you anyway!!!

I hope you will find the reason for your problem - I guess it's only a ridiculus little config entry missing or so...

Good Luck!

Daniel

[bgmf]

Thanks for your help - it was a little entry missing causing this problem:

had forgotten to write java:/MySqlDS in persistence.xml
instead i've written only MySqlDS

and there was no DS with such a name...

Thank you very much!

Have you allready solved your problem?

BGMF

[bgmf]

Hm...

I have no idea, but maybe you should change your persistence xml a little bit
I got a error because I had not entered the Hibernate Dialect

<properties>
 <property name="hibernate.dialect" value="org.hibernate.dialect.MySQLDialect" />
</properties>

how do you access those TestBean?

I was told to write an extra class with source code like this

try
 {
 Properties properties = new Properties();
 properties.put("java.naming.factory.initial","org.jnp.interfaces.NamingContextFactory");
 properties.put("java.naming.factory.url.pkgs","=org.jboss.naming:org.jnp.interfaces");
 properties.put("java.naming.provider.url","jnp://localhost:1099");

 InitialContext iContext = new InitialContext(properties);

 TologDatabaseQueryResponderRemote remote =
 (TologDatabaseQueryResponderRemote) iContext.lookup("TologResponderEAR/TologDatabaseQueryResponder/remote");
 }
 catch ( NamingException e )
 {
 throw new DatabaseQueryResponderException("NamingException while trying to connect to a remote interface:\n"+e.getLocalizedMessage());
 }

But I have to admit, that I also have the next problems - but ok - none of your business - you have your own problems...

Greetings
BGMF