Cannot get a connection, pool exhausted solution

Yesterday looked at the database connection pool, there are many open source connection pool, in order to facilitate the use of Tomcat with the connection pool,
Started looking for a few articles, did not succeed, the Tomcat graphics management interface to create a connection pool is also not good to use,
Later on the internet to find a piece of tomcat5.5 configuration article, finally is solved,
Follow the example below to try, refresh several times and then appear
Cannot get a connection, pool exhausted
Then a search was made that the connection pool was depleted,
Without closing con,
There are 3 solutions:
1 Restart Tomcat Server
2, maxactive the value of the big
3 Closing Conn in finally

Context Initctx=new InitialContext ();
DataSource ds = (DataSource) initctx.lookup ("Java:comp/env/jdbc/mysql");
C.getconnection ();
OUT.PRINTLN ("Query data from Database:<br>");
Statement stmt=conn.createstatement ();
ResultSet rs =stmt.executequery ("Select * from UserInfo");
while (Rs.next ())
{
Out.println (rs.getstring (1));
Out.println (rs.getstring (2));
}
Rs.close ();
Stmt.close ();
}
catch (Exception e)
{
E.printstacktrace ();
}
Finally
{
if (conn!=null)
Conn.close ();

}