i'm using netbeans to create the web service but now i'm facing this problem org.openide.util.NbPreferences getPreferencesProvider WARNING: NetBeans implementation of Preferences not foundand i ady include the org.openide.util jar and org.openide.util.loopup jar..i have no idea to fix it package pdfprint; import java.util.HashMap;import net.sf.jasperreports.engine.JasperPrint;import net.sf.jasperreports.engine.export.JRPdfExporter;import net.sf.jasperreports.engine.export.JRPdfExporterParameter;import com.jaspersoft.jasperserver.api.metadata.xml.domain.impl.ResourceDescriptor;import com.jaspersoft.ireport.jasperserver.JServer;import com.jaspersoft.ireport.jasperserver.ws.WSClient;import java.util.Locale;import java.util.Map;import net.sf.jasperreports.view.JasperViewer; public class Pdfprint { public static void main (String[] args) throws Exception {JServer server = new JServer();server.setUrl("http://localhost:8080/jasperserver/services/repository");server.setUsername("jasperadmin");server.setPassword("jasperadmin"); WSClient client = server.getWSClient(); //System.out.println("Version Check: " + client.getVersion()); ResourceDescriptor rd = new ResourceDescriptor();rd.setWsType(ResourceDescriptor.TYPE_REPORTUNIT);rd.setUriString("/reports/samples/AllAccounts"); //ResourceDescriptor asd = new ResourceDescriptor(); Map params = new HashMap(); params.put("Plb_Company", "Company"); params.put("Plb_Address", "Address"); params.put("Plb_Title","Title"); params.put("PCondition","SELECT * FROM v_doc_ticketing WHERE f_doc_no='MYCSB0000096'"); //System.out.print("124567"); //System.exit(0); //System.out.println(params);JasperPrint jp = client.runReport(rd, params); JasperViewer.viewReport(jp, false,Locale.GERMAN); JRPdfExporter exporter = new JRPdfExporter();exporter.setParameter(JRPdfExporterParameter.JASPER_PRINT, jp);} }and this is my full error in my netbeans org.openide.util.NbPreferences getPreferencesProviderWARNING: NetBeans implementation of Preferences not found[iNFO] AuthChallengeProcessor - -basic authentication scheme selectedException in thread "main" java.lang.NullPointerExceptionat net.sf.jasperreports.engine.JROrigin.equals(JROrigin.java:143)at java.util.HashMap.putForCreate(HashMap.java:522)at java.util.HashMap.readObject(HashMap.java:1156)at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)at java.lang.reflect.Method.invoke(Method.java:601)at java.io.ObjectStreamClass.invokeReadObject(ObjectStreamClass.java:1004)at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1872)at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1777)at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1347)at java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1970)at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1894)at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1777)at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1347)at java.io.ObjectInputStream.readObject(ObjectInputStream.java:369)at net.sf.jasperreports.engine.util.JRLoader.loadObject(JRLoader.java:198)at com.jaspersoft.ireport.jasperserver.ws.WSClient.runReport(WSClient.java:337)at pdfprint.Pdfprint.main(Pdfprint.java:43)