Hibernate connections are not closed even with C3P

Hibernate connections to MySQL my db are not closing. After clicking 10 times in like 10 second, I get this connection statistics from MySQL Workbench (in my development machine. I'm the only user).MySQL Workbench Server Status

I have those in place

C3P0 and running (checked from log4j, no problem related to C3P0 and seems running)
A ServletReqestListener which checks if there's an open session and closes it in requestDestroyed() method.
Hibernate Session object is being kept in ThreadLocal, so every request only have one connection, which opens at first query, and closes in ServletRequestListener.
Every time I open a session and close a session I output "Session Opened" and "Session Closed" to System.out as in the code example blow. At every request, every page refresh, I get "Session Opened" and after "Session Closed", repectively. So my little logic works. But the connection does not get closed.

My hibernate.cfg.xml

<property name="hibernate.bytecode.use_reflection_optimizer">false</property>
<property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="hibernate.connection.password">officenic</property>
<property name="hibernate.connection.url">jdbc:mysql://localhost/officenic</property>
<property name="hibernate.connection.username">officenic</property>
<property name="hibernate.dialect">org.hibernate.dialect.MySQL5InnoDBDialect</property>

<!-- configuration pool via c3p0 -->
<property name="hibernate.c3p0.acquire_increment">1</property>
<property name="hibernate.c3p0.idle_test_period">100</property> <!-- seconds -->
<property name="hibernate.c3p0.max_size">5</property>
<property name="hibernate.c3p0.max_statements">0</property>
<property name="hibernate.c3p0.min_size">1</property>
<property name="hibernate.c3p0.timeout">100</property> <!-- seconds -->

The code-block I call in everytime where I want to close the session.

if (session == null)
    return;

if (session.isOpen()) {

      if (session.isDirty())
         session.flush();

    session.close();
    System.out.println("Session closed");
}

Do I miss something?

回答1:

Well it seems I was creating SessionFactory everytime. There's a nice class here at the link, making SessionFactory static solved the problem. http://docs.jboss.org/hibernate/core/3.3/reference/en/html/tutorial.html#tutorial-firstapp-helpers

回答2:

private static final ThreadLocal<Session> session = new ThreadLocal<Session>();

public static void closeSession() throws HibernateException {
    Session s = session.get();
    if (s != null) {
        s.close();
        session.remove();
    }
}

actually I am doing like this and it works