How to use Model in GP

Question

Iam new to GP.I have created a Model.Now how to define the parameters in the getDescription,getComplete,execute.
Please help me in this way or anyone can explain the functions in getDescription.How to pass values.
try {
     IWDTextAccessor textAccessor = wdComponentAPI.getTextAccessor(); //To retrieve Messages from Message Pool
     GPWebDynproResourceAccessor resourceAccessor = new GPWebDynproResourceAccessor(textAccessor);
     IGPTechnicalDescription technicalDescription = GPCallableObjectFactory.createTechnicalDescription("CO_NAME","CO_DESCRIPTION",resourceAccessor,locale);
//        Pre-existing structure for output parameters
     IGPStructureInfo output = technicalDescription.getOutputStructureInfo();
//        Create the attributes in the output structure
     IGPAttributeInfo userId = output.addAttribute("UserID", IGPAttributeInfo.BASE_STRING);
     userId.setMultiplicity(IGPAttributeInfo.MULITIPLICITY_1_1);
//        add result state
     IGPCOResultStateInfo success = technicalDescription.addResultState("Success");
     success.setDescriptionKey("Success_desc");
     return technicalDescription;
     } catch (GPInvocationException e) {
     return null;

Answer 1

Hi,
in getDescription you must declare the input, output and the states of the co. Smth like that:
// Description of the future callable object
IGPTechnicalDescription technicalDescription =
                 GPCallableObjectFactory.createTechnicalDescription(
                    "SelectUserCO",
                    "Select from available users",
                    resourceAccessor,
                    locale);
// input structure
IGPStructureInfo input =
technicalDescription.getInputStructureInfo();
IGPStructureInfo providerProfileEntryInput =
                 input.addStructure("user1");
              providerProfileEntryInput.setMultiplicity(IGPStructureInfo.MULITIPLICITY_0_N);
              providerProfileEntryInput.addAttribute("name", IGPAttributeInfo.BASE_STRING);
// structure for output parameters
IGPStructureInfo output =
                 technicalDescription.getOutputStructureInfo();
IGPStructureInfo providerProfileEntryOutput =
                      output.addStructure("User2");
              providerProfileEntryOutput.setMultiplicity(IGPStructureInfo.MULITIPLICITY_0_N);
              providerProfileEntryOutput.addAttribute("name", IGPAttributeInfo.BASE_STRING);
//add result state
IGPCOResultStateInfo success =
                 technicalDescription.addResultState("Success");
              success.setDescriptionKey("Success_desc");
Then in execute you should map your input to our context. You have node elements for your structure nodes and you can add the new elements you create/map to the user.
Important are maybe:
executionContext and the wdContext variables. Declare them under (//@@begin others, //@@end provided by SAP):
  //@@begin others
       private IGPExecutionContext executionContext;
     IWDTextAccessor textAccessor;
     GPWebDynproResourceAccessor resourceAccessor;
  //@@end
and then instantiation in the constructor:
    this.wdThis = wdThis;
    this.wdContext = wdThis.wdGetContext();
    this.wdControllerAPI = wdThis.wdGetAPI();
    this.wdComponentAPI = wdThis.wdGetAPI().getComponent();
this help page can help:
http://help.sap.com/saphelp_nwce10/helpdata/en/fd/afb4429027da11e10000000a155106/content.htm
best regards,
v s