SAP JCO JAVA Could not initialize class com.sap.conn.jco.JCo

Question

i want to use SAP JCO to select user data for my java program.

But all i got is:

Sep 23, 2014 1:34:28 PM org.apache.catalina.core.StandardWrapperValve invoke
SEVERE: Servlet.service() for servlet [StepByStepClient] in context with path [/Formularmanager-test] threw exception [Servlet execution threw an exception] with root cause
java.lang.NoClassDefFoundError: Could not initialize class com.sap.conn.jco.JCo
    at com.sap.conn.jco.JCoDestinationManager.getDestination(JCoDestinationManager.java:61)
    at com.pferd.itdienste.sap.StepByStepClient.step1Connect(StepByStepClient.java:125)
    at com.pferd.itdienste.sap.StepByStepClient.processRequest(StepByStepClient.java:356)
    at com.pferd.itdienste.sap.StepByStepClient.doGet(StepByStepClient.java:70)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:621)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:222)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123)
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:99)
    at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:953)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
    at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1023)
    at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:589)
    at org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.run(AprEndpoint.java:1852)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
    at java.lang.Thread.run(Unknown Source)

For a test i use the example script "StepByStepClient" and i have modify this only, so i can use it as an web servlet.

All files from sap jco are on "C:\sapjco30P_11-10005326" and i have this folder registered in the system pfad variable.

At this moment i dont know where my error is! So i need help, please!

SAP Java Connector Java Runtime Operating System: Windows Server 2012 6.2 for amd64 Java VM: 1.7.0_60 Oracle Corporation Default charset: windows-1252

Versions

• JCo API: 3.0.11 (2014-04-15)
• JCo middleware: JavaRfc 2.2.12
• JCo library: 720.612

Library Paths

• Path to JCo archive: C:\sapjco30P_11-10005326\sapjco3.jar
• Path to JCo library: C:\sapjco30P_11-10005326\sapjco3.dll

Eclipse Juno XAMPP Tomcat 7

package com.pferd.itdienste.sap;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.Properties;
import java.util.concurrent.CountDownLatch;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.sap.conn.jco.AbapException;
import com.sap.conn.jco.JCoContext;
import com.sap.conn.jco.JCoDestination;
import com.sap.conn.jco.JCoDestinationManager;
import com.sap.conn.jco.JCoException;
import com.sap.conn.jco.JCoField;
import com.sap.conn.jco.JCoFunction;
import com.sap.conn.jco.JCoFunctionTemplate;
import com.sap.conn.jco.JCoStructure;
import com.sap.conn.jco.JCoTable;
import com.sap.conn.jco.ext.DestinationDataProvider;

@WebServlet(name = "StepByStepClient", urlPatterns = {"/StepByStepClient"})
public class StepByStepClient extends HttpServlet
{
    static String ABAP_AS = "ABAP_AS_WITHOUT_POOL";
    static String ABAP_AS_POOLED = "ABAP_AS_WITH_POOL";
    static String ABAP_MS = "ABAP_MS_WITHOUT_POOL";    
    static
    {
        Properties connectProperties = new Properties();
        connectProperties.setProperty(DestinationDataProvider.JCO_ASHOST, "HOST");
        connectProperties.setProperty(DestinationDataProvider.JCO_SYSNR,  "01");
        connectProperties.setProperty(DestinationDataProvider.JCO_CLIENT, "200");
        connectProperties.setProperty(DestinationDataProvider.JCO_USER,   "USER");
        connectProperties.setProperty(DestinationDataProvider.JCO_PASSWD, "PASSWORD");
        connectProperties.setProperty(DestinationDataProvider.JCO_LANG,   "en");
        createDataFile(ABAP_AS, "jcoDestination", connectProperties);

        connectProperties.setProperty(DestinationDataProvider.JCO_POOL_CAPACITY, "3");
        connectProperties.setProperty(DestinationDataProvider.JCO_PEAK_LIMIT,    "10");
        createDataFile(ABAP_AS_POOLED, "jcoDestination", connectProperties);

        connectProperties.clear();
        connectProperties.setProperty(DestinationDataProvider.JCO_MSHOST, "HOST");
        connectProperties.setProperty(DestinationDataProvider.JCO_R3NAME,  "SID");
        connectProperties.setProperty(DestinationDataProvider.JCO_CLIENT, "200");
        connectProperties.setProperty(DestinationDataProvider.JCO_USER,   "USER");
        connectProperties.setProperty(DestinationDataProvider.JCO_PASSWD, "PASSWORD");
        connectProperties.setProperty(DestinationDataProvider.JCO_GROUP, "GROUP");
        connectProperties.setProperty(DestinationDataProvider.JCO_LANG,   "en");
        createDataFile(ABAP_MS, "jcoDestination", connectProperties);
    }

    /** 
     * Handles the HTTP <code>GET</code> method.
     * @param request servlet request
     * @param response servlet response
     * @throws ServletException if a servlet-specific error occurs
     * @throws IOException if an I/O error occurs
     */
    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        try {
            processRequest(request, response);
        } catch (JCoException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }

    /** 
     * Handles the HTTP <code>POST</code> method.
     * @param request servlet request
     * @param response servlet response
     * @throws ServletException if a servlet-specific error occurs
     * @throws IOException if an I/O error occurs
     */
    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        try {
            processRequest(request, response);
        } catch (JCoException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }

    /** 
     * Returns a short description of the servlet.
     * @return a String containing servlet description
     */
    @Override
    public String getServletInfo() {
        return "Short description";
    }// </editor-fold>    

    static void createDataFile(String name, String suffix, Properties properties)
    {
        File cfg = new File(name+"."+suffix);
        if(!cfg.exists())
        {
            try
            {
                FileOutputStream fos = new FileOutputStream(cfg, false);
                properties.store(fos, "for tests only !");
                fos.close();
            }
            catch (Exception e)
            {
                throw new RuntimeException("Unable to create the destination file " + cfg.getName(), e);
            }
        }
    }


    public static void step1Connect() throws JCoException
    {
        JCoDestination destination = JCoDestinationManager.getDestination(ABAP_AS);
        System.out.println("Attributes:");
        System.out.println(destination.getAttributes());
        System.out.println();

        destination = JCoDestinationManager.getDestination(ABAP_MS);
        System.out.println("Attributes:");
        System.out.println(destination.getAttributes());
        System.out.println();
    }

    public static void step2ConnectUsingPool() throws JCoException
    {
        JCoDestination destination = JCoDestinationManager.getDestination(ABAP_AS_POOLED);
        destination.ping();
        System.out.println("Attributes:");
        System.out.println(destination.getAttributes());
        System.out.println();
    }

    public static void step3SimpleCall() throws JCoException
    {
        JCoDestination destination = JCoDestinationManager.getDestination(ABAP_AS_POOLED);
        JCoFunction function = destination.getRepository().getFunction("STFC_CONNECTION");
        if(function == null)
            throw new RuntimeException("BAPI_COMPANYCODE_GETLIST not found in SAP.");

        function.getImportParameterList().setValue("REQUTEXT", "Hello SAP");

        try
        {
            function.execute(destination);
        }
        catch(AbapException e)
        {
            System.out.println(e.toString());
            return;
        }

        System.out.println("STFC_CONNECTION finished:");
        System.out.println(" Echo: " + function.getExportParameterList().getString("ECHOTEXT"));
        System.out.println(" Response: " + function.getExportParameterList().getString("RESPTEXT"));
        System.out.println();
    }

    public static void step3WorkWithStructure() throws JCoException
    {
        JCoDestination destination = JCoDestinationManager.getDestination(ABAP_AS_POOLED);
        JCoFunction function = destination.getRepository().getFunction("RFC_SYSTEM_INFO");
        if(function == null)
            throw new RuntimeException("RFC_SYSTEM_INFO not found in SAP.");

        try
        {
            function.execute(destination);
        }
        catch(AbapException e)
        {
            System.out.println(e.toString());
            return;
        }

        JCoStructure exportStructure = function.getExportParameterList().getStructure("RFCSI_EXPORT");
        System.out.println("System info for " + destination.getAttributes().getSystemID() + ":\n");
        for(int i = 0; i < exportStructure.getMetaData().getFieldCount(); i++) 
        {
            System.out.println(exportStructure.getMetaData().getName(i) + ":\t" + exportStructure.getString(i));
        }
        System.out.println();

        //JCo still supports the JCoFields, but direct access via getXX is more efficient as field iterator
        System.out.println("The same using field iterator: \nSystem info for " + destination.getAttributes().getSystemID() + ":\n");
        for(JCoField field : exportStructure)
        {
            System.out.println(field.getName() + ":\t" + field.getString());
        }
        System.out.println();
    }

    public static void step4WorkWithTable() throws JCoException
    {
        JCoDestination destination = JCoDestinationManager.getDestination(ABAP_AS_POOLED);
        JCoFunction function = destination.getRepository().getFunction("BAPI_COMPANYCODE_GETLIST");
        if(function == null)
            throw new RuntimeException("BAPI_COMPANYCODE_GETLIST not found in SAP.");

        try
        {
            function.execute(destination);
        }
        catch(AbapException e)
        {
            System.out.println(e.toString());
            return;
        }

        JCoStructure returnStructure = function.getExportParameterList().getStructure("RETURN");
        if (! (returnStructure.getString("TYPE").equals("")||returnStructure.getString("TYPE").equals("S"))  )   
        {
           throw new RuntimeException(returnStructure.getString("MESSAGE"));
        }

        JCoTable codes = function.getTableParameterList().getTable("COMPANYCODE_LIST");
        for (int i = 0; i < codes.getNumRows(); i++) 
        {
            codes.setRow(i);
            System.out.println(codes.getString("COMP_CODE") + '\t' + codes.getString("COMP_NAME"));
        }

        codes.firstRow();
        for (int i = 0; i < codes.getNumRows(); i++, codes.nextRow()) 
        {
            function = destination.getRepository().getFunction("BAPI_COMPANYCODE_GETDETAIL");
            if (function == null) 
                throw new RuntimeException("BAPI_COMPANYCODE_GETDETAIL not found in SAP.");

            function.getImportParameterList().setValue("COMPANYCODEID", codes.getString("COMP_CODE"));
            function.getExportParameterList().setActive("COMPANYCODE_ADDRESS",false);

            try
            {
                function.execute(destination);
            }
            catch (AbapException e)
            {
                System.out.println(e.toString());
                return;
            }

            returnStructure = function.getExportParameterList().getStructure("RETURN");
            if (! (returnStructure.getString("TYPE").equals("") ||
                   returnStructure.getString("TYPE").equals("S") ||
                   returnStructure.getString("TYPE").equals("W")) ) 
            {
                throw new RuntimeException(returnStructure.getString("MESSAGE"));
            }

            JCoStructure detail = function.getExportParameterList().getStructure("COMPANYCODE_DETAIL");

            System.out.println(detail.getString("COMP_CODE") + '\t' +
                               detail.getString("COUNTRY") + '\t' +
                               detail.getString("CITY"));
        }//for
    }

    /**
     * this example shows the "simple" stateful call sequence. Since all calls belonging to one
     * session are executed within the same thread, the application does not need
     * to take care about the SessionReferenceProvider. MultithreadedExample.java 
     * illustrates the more complex scenario, where the calls belonging to one session are 
     * executed from different threads.
     * 
     * Note: this example uses Z_GET_COUNTER and Z_INCREMENT_COUNTER. The most ABAP systems
     * contain function modules GET_COUNTER and INCREMENT_COUNTER, that are not remote enabled.
     * Copy these functions to Z_GET_COUNTER and Z_INCREMENT_COUNTER (or implement as wrapper)
     * and mark they remote enabled 
     * @throws JCoException
     */
    public static void step4SimpleStatefulCalls() throws JCoException
    {
        final JCoFunctionTemplate incrementCounterTemplate, getCounterTemplate;

        JCoDestination destination = JCoDestinationManager.getDestination(ABAP_MS);
        incrementCounterTemplate = destination.getRepository().getFunctionTemplate("Z_INCREMENT_COUNTER");
        getCounterTemplate = destination.getRepository().getFunctionTemplate("Z_GET_COUNTER");
        if(incrementCounterTemplate == null || getCounterTemplate == null)
            throw new RuntimeException("This example cannot run without Z_INCREMENT_COUNTER and Z_GET_COUNTER functions");

        final int threadCount = 5;
        final int loops = 5;
        final CountDownLatch startSignal = new CountDownLatch(threadCount);
        final CountDownLatch doneSignal = new CountDownLatch(threadCount);

        Runnable worker = new Runnable()
        {
            public void run()
            {
                startSignal.countDown();
                try
                {
                    //wait for other threads
                    startSignal.await();

                    JCoDestination dest = JCoDestinationManager.getDestination(ABAP_MS);
                    JCoContext.begin(dest);
                    try
                    {
                        for(int i=0; i < loops; i++)
                        {
                            JCoFunction incrementCounter = incrementCounterTemplate.getFunction();
                            incrementCounter.execute(dest);
                        }
                        JCoFunction getCounter = getCounterTemplate.getFunction();
                        getCounter.execute(dest);

                        int remoteCounter = getCounter.getExportParameterList().getInt("GET_VALUE");
                        System.out.println("Thread-" + Thread.currentThread().getId() + 
                                " finished. Remote counter has " + (loops==remoteCounter?"correct":"wrong") + 
                                " value [" + remoteCounter + "]");
                    }
                    finally
                    {
                        JCoContext.end(dest);                    
                    }
                }
                catch(Exception e)
                {
                    System.out.println("Thread-" + Thread.currentThread().getId() + " ends with exception " + e.toString());
                }

                doneSignal.countDown();
            }
        };

        for(int i = 0; i < threadCount; i++)
        {
            new Thread(worker).start();
        }

        try
        {
            doneSignal.await();
        }
        catch(Exception e)
        {
        }

    }

    protected void processRequest(HttpServletRequest request, HttpServletResponse response) throws JCoException
    {
        step1Connect();
        step2ConnectUsingPool();
        step3SimpleCall();
        step4WorkWithTable();
        step4SimpleStatefulCalls();
    }
}

Answer 1

The jar-file containing the com.sap.conn.jco.JCo is not on the classpath. Are you sure that you have correctly set it as a JVM parameter? Adding it to the PATH-variable is not going to work since your JVM does not read that variable.