getting bad connection

[Frank]

Hello,

I have this in a class to return a Cayenne connection.
It works ok at first, but after a number of calls, it fails.

public class DBConnections {....
public Connection getAS400Connection() {
try {
    Configuration config = Configuration.getSharedConfiguration();
    DataDomain domain = config.getDomain();
    DataNode node = domain.getNode("cdsurveyDomainNode1");
    return node.getDataSource().getConnection();
 } catch (Exception ex) {
  return null;
 }
}

Thanks

Frank