Open connections between AS Java and AS ABAP when using JRA

Question

Hi, we have a problem with open connections and hope that someone here could give me hint where to find a solution.
The situation is that we open a connection from a Java application to an AS ABAP. In detail, the application first connects to a statefull session bean on the AS Java by RMI. The bean communicates with the associated AS ABAP by the Java Resource Adapter (JRA).
All interactions between all components work correctly. But even after we close the application, manually close of the connections (on side of the AS Java) , remove all created and used session beans there are still open connections between the AS ABAP and the AS Java.
The transaction smgw (Gateway Monitor) shows open connections from jlaunch to our local SAP gateway using the internal communication protocol. Obviously, the established connections are not closed, even when they are open for a week or longer.
After opening 100 connections, the AS ABAP denies additional connection attempts.
We have been able to close all open connections by restarting the AS Java or by restarting the Connector over the Visual Administrator (path: Cluster – Server – Services – Connector Container – “select the right connector” – stop / start).
We have developed our application similar to the tutorial from [https://www.sdn.sap.com/irj/servlet/prt/portal/prtroot/docs/library/uuid/ad09cd07-0a01-0010-93a9-933e247d3ba4]
Can someone explain to us why the connections stay open for so long? Is there no timeout mechanism? Or is there some way to close the connections from our Java application?

Answer 1

Hello,
maybe someone can help us with our problem.
We have developed our application similar to the tutorial from https://www.sdn.sap.com/irj/servlet/prt/portal/prtroot/docs/library/uuid/ad09cd07-0a01-0010-93a9-933e247d3ba4 and it was running without problem with the SP12, now we change our system to SP16 and we are having the problem described in note 1083348, but as you can see, for us it was working with SP12 and now it doesn't work with SP16....
Here is part of our code....
    public List getAll() {
        String functionName = "bla";
        try {
            openConnection();
            MappedRecord response = (MappedRecord) interaction.execute(null, request);
            MappedRecord record = (MappedRecord) response.get("E_S_RETURN_CODE");
            if (((String) record.get("RETURN_CODE")).equalsIgnoreCase("E")) {
                throw new SQLException((String) record.get("RETURN_TXT"));
        catch (ResourceException exc) {
            throw new EJBException(".");
        catch (SQLException exc) {
            throw new EJBException(".");
        finally {
            closeConnection();
    protected void openConnection() {
        try {
            connection = connectionFactory.getConnection();
            interaction = connection.createInteraction();
        catch (ResourceException exc) {
            interaction = null;
            connection = null;
            throw new EJBException(getExceptionText(exc));
  protected void closeConnection() {
       try {
            if (interaction != null) {
                interaction.close();
            if (connection != null) {
                connection.close();
        catch (ResourceException exc) {
            throw new EJBException(".");
With that code we are getting this error: "Connection handle is already closed and no longer associated with a managed connection" everytime we try to close the connection in the method closeConnection().
We were thinking that maybe we should not close the connections, because the were already close, and tried not to close the connection (connection.close()), but then after a few time we are getting the following error, because we are not closing the connections:
Connection to ABAP System could not be opened, because the Connection Factory returns "Cannot get connection for 120 seconds. Possible reasons: 1) Connections are cached within SystemThread(can be any server service or any code invoked within SystemThread in the SAP J2EE Engine), 2) The pool size of adapter "eis/..." is not enough according to the current load of the system or 3) The specified time to wait for connection is not enough according to the pool size and current load of the system. In case 1) the solution is to check for cached connections using the Connector Service list-conns command, in case 2) to increase the size of the pool and in case 3) to increase the time to wait for connection property. In case of application thread, there is an automatic mechanism which detects unclosed connections and unfinished transactions.". Please check the connection defined for the Connection Factory of the Java Resource Adapter with JNDI name...
Any help?