Creating an Adaptive RFC2 Sample Application without using Web Dynpro

Prerequisites

You have the knowledge of Servlet programming.
You have the access to an R/3 system.
BAPI_FLIGHT_GETLIST RFM exists on the R/3 system.
You have administrator access to an SAP Java AS.
You have launched SAP NetWeaver Developer Studio.

Context

This topic provides instructions on creating a sample Servlet application that executes the BAPI_FLIGHT_GETLIST remote function module (RFM), and displays the flightlist in a browser window.

Procedure

Create a new project of type Dynamic Web Project .
In the Project name field, enter ARFC2Generic and select the Add project to an EAR checkbox. Do not change the other settings and click Next .
Dynamic Web Module, Java, and SAP Specific Web Module are selected by default. Do not change these settings and click Next .
Ensure that Generate Deployment Descriptor is selected and click Finish .
In the Project Explorer, choose ARFC2GenericEAR EARContent META-INF application-j2ee-engine.xml file. Select the Source tab and insert the following code between <application-j2ee-engine> and </application-j2ee-engine> .

Save and close the file.
In the Project Explorer, open the context menu for Java Resources: src under ARFC2Generic project. In the context menu choose New Other Web Servlet and click Next .
Enter the Java package as com.test and class name as ARFC2GenericServlet . Click Next .
Leave the other entries unchanged and click Finish .
In the Project Explorer, open the context menu for ARFC2Generic and select Build Path Configure Build Path . Select the Libraries tab page and then select Add External JARs .

Navigate to the following paths to add the external JARS one after the other.
- <J2ee_engine_install_path>/<SID>/J0x/j2ee/cluster/bin/ext/tc~cm~arfc2/ and select cm_arfc2_api.jar. Click OK .
- <J2ee_engine_install_path>/<SID>/J0x/j2ee/cluster/bin/ext/com.sap.tc.cmi/lib and select com.sap.tc.cmi_api.jar. Click OK .
- <J2ee_engine_install_path>/<SID>/J0x/j2ee/cluster/bin/ext/tc~cm~base/lib and select cmi_baseimpl_api.jar. Click OK .
- <IDE_install_path>\eclipse\plugins\com.sap.mw.jco3_<build_number>\lib and select sapjco3_IDE.jar. Click OK .

Declare the following variables in the servlet class that you have created:

String[] rfmName = {"BAPI_FLIGHT_GETLIST"}; // RFM to be executed
String metadataDestination = "WD_RFC_METADATA_DEST"; // Metadata destination on NWA
String modelDestination = "WD_MODELDATA_DEST"; // Model Execution Destination on NWA
String postFix = "_Input"; // postfix for naming input modelClass
String outputRelation = "Output"; // the output relation

Create the two new JCo destinations WD_RFC_METADATA_DEST and WD_MODELDATA_DEST in the SAP NetWeaver Administrator.

More information: SAP JCo Configuration

Inside the doGet() method, insert the following code snippet:

    PrintWriter writer = response.getWriter();
                response.setContentType("text/html");
                
                writer.println("<HTML><BODY>");
                
                //Create the modelInfo for the ARFC2 model
                writer.println("<P>1...Creating Metadata");       
                ARFC2ModelInfo modelInfo = createMetadata();
                
                //Create the ARFC2 model
                writer.println("<P>2..Creating Model");
                ARFC2Model model = new ARFC2Model(modelInfo, modelDestination);
        
                //Create the executable model object
        writer.println("<P>3..Creating Executable Model Object (Input Model Object)");
        ARFC2GenericModelClassExecutable executable = (ARFC2GenericModelClassExecutable)model.createModelObject((new StringBuilder("Bapi_Flight_Getlist")).append(postFix).toString());
        
                //Execute the executable model object
        executeModelObject(executable, writer);
        
                writer.println("Execution successfully completed");
                writer.println("</BODY></HTML>");

Introduce the two functions into the servlet class, as shown below:

private ARFC2ModelInfo createMetadata() {
                ARFC2ModelInfo modelInfo = ARFC2ModelInfo.importMetadataFromBackend("Metadata", Locale.getDefault(), rfmName, metadataDestination, new HashMap(), null, null);

//No changes to metadata are allowed after the next step
                modelInfo.finishMetadataCreation();
                return modelInfo;
        }

private void executeModelObject(ARFC2GenericModelClassExecutable executable, PrintWriter writer)
    {
        try
        {
            writer.println("<P>4..setting input Model Object params");
            executable.setAttributeValue("Max_Rows", Integer.valueOf(500));
            
            writer.println("<P>5..Execute");
            executable.execute();
            
            writer.println("<P>6..get output ModelObject");
            ARFC2GenericModelClass outputObj = (ARFC2GenericModelClass)executable.getRelatedModelObject(outputRelation);
            Collection collection = outputObj.getRelatedModelObjects("Flight_List");
            Iterator iterator = collection.iterator();
            int i = 0;
            writer.println("<P>7..Iterate results");
            writer.println("<table border = 1>");
            writer.println("<tr><td>Airline ID</td><td>Airline</td><td>Connect ID</td><td>Flight Date</td><t" +
"d>Airport From</td><td>City From</td><td>Airport To</td><td>City To</td><td>Dep " +
"time</td><td>Arr Time</td><td>Currency</td><td>Currency_ISO</td></tr>"
);
            for(; iterator.hasNext(); writer.println("</tr>"))
            {
                ARFC2GenericModelClass modelClass = (ARFC2GenericModelClass)iterator.next();
                writer.println("<tr>");
                writer.println((new StringBuilder("<td>")).append((String)modelClass.getAttributeValue("Airlineid")).append("</td>").toString());
                writer.println((new StringBuilder("<td>")).append((String)modelClass.getAttributeValue("Airline")).append("</td>").toString());
                writer.println((new StringBuilder("<td>")).append((String)modelClass.getAttributeValue("Connectid")).append("</td>").toString());
                writer.println((new StringBuilder("<td>")).append(modelClass.getAttributeValue("Flightdate")).append("</td>").toString());
                writer.println((new StringBuilder("<td>")).append((String)modelClass.getAttributeValue("Airportfr")).append("</td>").toString());
                writer.println((new StringBuilder("<td>")).append((String)modelClass.getAttributeValue("Cityfrom")).append("</td>").toString());
                writer.println((new StringBuilder("<td>")).append((String)modelClass.getAttributeValue("Airportto")).append("</td>").toString());
                writer.println((new StringBuilder("<td>")).append((String)modelClass.getAttributeValue("Cityto")).append("</td>").toString());
                writer.println((new StringBuilder("<td>")).append(modelClass.getAttributeValue("Deptime")).append("</td>").toString());
                writer.println((new StringBuilder("<td>")).append(modelClass.getAttributeValue("Arrtime")).append("</td>").toString());
                writer.println((new StringBuilder("<td>")).append(modelClass.getAttributeValue("Curr")).append("</td>").toString());
                writer.println((new StringBuilder("<td>")).append(modelClass.getAttributeValue("Curr_Iso")).append("</td>").toString());
            }

            writer.println("</table>");
        }
        catch(Exception e)
        {
            writer.println("<P>***Exception while execution");
        }
    }

If you get any compilation errors, then right-click anywhere in the Java Editor, select Source and then select Organize Imports.

In the Project Explorer, under ARFC2Generic project, expand the Java Resources: src node and in the context menu of the ARFC2GenericServlet.java , select Run As Run on Server.
In this screen, select the SAP Server (J2EE engine) that you want to run the application on and click Next.
Ensure that ARFC2GenericEAR is present under the Configured projects . Click Finish.

Results

A pop up appears if the deployment is successful. Click OK , and the results of the application execution are displayed on a servlet within the SAP NetWeaver Developer Studio.