Thank U 4 all from beginning !!!!!!!
my code is below:


private InitialContext initial = null;
private DataSource dataSource = null;


public synchronized Connection getConnection(String name) {
try {
if(name==null) name = "";
initial = new InitialContext();
dataSource = (DataSource) initial.lookup("java:/jdbc/"+name);
Connection con = dataSource.getConnection();
return con;
} catch (SQLException e) {
System.out.print("can not get connection ...java:/jdbc/"+name);
System.out.println("SQLException cause ~~~"+e.getMessage());
e.printStackTrace();
return null;
} catch (NamingException e1) {
System.out.println("NamingException cause ~~~"+e1.getMessage());
e1.printStackTrace();
return null;
} finally{
try {
if(initial!=null) initial.close();
} catch (NamingException e) {
System.out.println("Error Closing InitialContext cause---->"+e.getMessage());
e.printStackTrace();
}
}
}


it always work perfect ,but sometimes the system will throw the follow Exception , this is the details:


INFO [STDOUT] can not get connection...java:/jdbc/et
ERROR [STDERR] java.sql.SQLException: JZ006: capture io exception :com.sybase.jdbc3.jdbc.SybConnectionDeadException: JZ0C0: the connection has already been closed .



here is my -ds.xml configuration


<no-tx-datasource>
<jndi-name>jdbc/et</jndi-name>
<connection-url>jdbc:sybase:Tds:127.0.0.1:2638?ServiceName=et</connection-url>
<driver-class>com.sybase.jdbc3.jdbc.SybDriver</driver-class>
<user-name>DBA</user-name>
< p a s s w o r d>**</ p a s s w o r d >
<idle-timeout-minutes>5</idle-timeout-minutes>
<blocking - timeout - millis>10000</blocking - timeout - millis>
<exception-sorter-class-name>org.jboss.resource.adapter.jdbc.vendor.SybaseExceptionSorter</exception-sorter-class-name>
<min-pool-size>10</min-pool-size>
<max-pool-size>1000</max-pool-size>
<prepared-statement-cache-size>0</prepared-statement-cache-size>

<type-mapping>Sybase</type-mapping>

</no-tx-datasource>



help me please
thank u everyone !!!!!!!!!!!!
tips:
shoud i add this issue in the xml files to avoid that exception ?
<check-valid-connection-sql>some check sql</check-valid-connection-sql>


and make the initialcontext , datasource to static ?