JCO_ERROR_RESOURCE: Destination ABAP_AS_WITHOUT_POOL does not exist... error while connecting via JCo

Question

I am working on a Java app that needs to get data from our SAP system laying in SAP table. I try to connect the SW with SAP system using SAP Java Connector 3.X, but I'm having trouble with the Destination.

I used the Code-Examples that came with the SAP Java Connector.

public class CustomDestinationDataProvider {

static class MyDestinationDataProvider implements DestinationDataProvider {
    private DestinationDataEventListener eL;
    private HashMap<String, Properties> secureDBStorage = new HashMap<String, Properties>();
    
    public Properties getDestinationProperties(String ABAP_AS) {
        try {
            //read the destination from DB
            Properties p = secureDBStorage.get(ABAP_AS);

            if(p!=null) {
                //check if all is correct, for example
                if(p.isEmpty())
                    throw new DataProviderException(DataProviderException.Reason.INVALID_CONFIGURATION, "destination configuration is incorrect", null);

                return p; 
                }
            
            return null; 
            } catch(RuntimeException re) {
            throw new DataProviderException(DataProviderException.Reason.INTERNAL_ERROR, re);
        }
    }

    //An implementation supporting events has to retain the eventListener instance provided
    //by the JCo runtime. This listener instance shall be used to notify the JCo runtime
    //about all changes in destination configurations.
    public void setDestinationDataEventListener(DestinationDataEventListener eventListener) {
        this.eL = eventListener;
    }

    public boolean supportsEvents() {
        return true;
    }

    //implementation that saves the properties in a very secure way
    void changeProperties(String ABAP_AS, Properties properties) {
        synchronized(secureDBStorage) {
            if(properties==null) {
                if(secureDBStorage.remove(ABAP_AS)!=null)
                    eL.deleted(ABAP_AS);
            } else {
                secureDBStorage.put(ABAP_AS, properties);
                eL.updated(ABAP_AS); // create or updated
            }
        }
    }
} // end of MyDestinationDataProvider

//business logic
void executeCalls(String ABAP_AS) {
    JCoDestination dest;
    try {
        dest = JCoDestinationManager.getDestination(ABAP_AS);
        dest.ping();
        System.out.println("Destination " + ABAP_AS + " works");
    } catch(JCoException e) {
        e.printStackTrace();
        System.out.println("Execution on destination " + ABAP_AS + " failed");
    }
}

static Properties getDestinationPropertiesFromUI() {
    //adapt parameters in order to configure a valid destination
    Properties connectProperties = new Properties();
    connectProperties.setProperty(DestinationDataProvider.JCO_ASHOST, "XXX");
    connectProperties.setProperty(DestinationDataProvider.JCO_SYSNR,  "XX");
    connectProperties.setProperty(DestinationDataProvider.JCO_CLIENT, "XXX");
    connectProperties.setProperty(DestinationDataProvider.JCO_USER,   "XXX");
    connectProperties.setProperty(DestinationDataProvider.JCO_PASSWD, "XXX");
    connectProperties.setProperty(DestinationDataProvider.JCO_LANG,   "XX");
    createDestinationDataFile(ABAP_AS, connectProperties);
    return connectProperties;
}

static void createDestinationDataFile(String ABAP_AS, Properties connectProperties) {
    File destCfg = new File(ABAP_AS + ".jcoDestination");
    try {
        FileOutputStream fos = new FileOutputStream(destCfg, false);
        connectProperties.store(fos, "for tests only!");
        fos.close();
    } catch (Exception e) {
        throw new RuntimeException("Unable to create the destination files", e);
    }
} 

}

This is the error message I get from NetBeans:

Destination ABAP_AS_WITHOUT_POOL works
Execution on destination ABAP_AS_WITHOUT_POOL failed
com.sap.conn.jco.JCoException: (106) JCO_ERROR_RESOURCE: Destination 
    ABAP_AS_WITHOUT_POOL does not exist
at com.sap.conn.jco.rt.DefaultDestinationManager.update(DefaultDestinationManager.java:217)
at com.sap.conn.jco.rt.DefaultDestinationManager.searchDestination(DefaultDestinationManager.java:382)
at com.sap.conn.jco.rt.DefaultDestinationManager.getDestinationInstance(DefaultDestinationManager.java:100)
at com.sap.conn.jco.JCoDestinationManager.getDestination(JCoDestinationManager.java:104)
at jcotest2.CustomDestinationDataProvider.executeCalls(CustomDestinationDataProvider.java:92)
at jcotest2.Main.main(Main.java:39)
BUILD SUCCESSFUL (total time: 2 seconds)

Answer 1

It looks like your code keeps the logon data in the HashMap "secureDBStorage". Where do you fill this HashMap?

Also: what do you need the method "createDestinationDataFile()" for, if you are using a HashMap and not a file?

Edit: as this post got deleted by review, I'm trying to make it more precise now. So there are two problems with your code:

1. You keep the logon parameters of your backend systems in a HashMap named "secureDBStorage", but you did not fill this map with parameters for the system/destination named "ABAP_AS_WITHOUT_POOL".

2. Your code still contains the method "createDestinationDataFile()", which was probably copied from the sample program and then forgotten to delete. As your program is using a HashMap for storing the logon parameters and not the file system, you can delete this method. (Only confuses the program.)

Answer 2

Prior to calling the destination you should create it in Configuration Manager of SAP Java Application Server (NWA Manager) and then only call it.

https://help.sap.com/doc/saphelp_nwpi711/7.1.1/enUS/07/0d27932264284b883dab13ce1008a6/frameset.htm

Here is the sample:

static String ABAP_AS = "WD_MODELDATA_DEST";

PrintWriter out = response.getWriter();
     JCoDestination destination;
    try {
        destination = JCoDestinationManager.getDestination(ABAP_AS);
        out.println("Attributes:");
        out.println(destination.getAttributes());
        out.println();
    } catch (JCoException e) {
        e.printStackTrace();
        out.println(e.getMessage());
    }

I don't see where you fill ABAP_AS variable in your code like in the sample.