wcf data service problem

public class sample
{
sample()
{
}
 public IQueryable GetData()
        {
            System.Net.WebRequest request = System.Net.WebRequest.Create("url");
                      
             return methodname(arg1,ar2);//here actualy retuning the data as iqueryable and to another class
            //return null;
        }

public class MyCustomDataSource
   {
       public MyCustomDataSource()
       {
           sample s = new sample();
           s.GetData();

       }
   }

[System.ServiceModel.ServiceBehavior(IncludeExceptionDetailInFaults = true)]
       public class DataService : DataService< MyCustomDataSource >
   {
       // This method is called only once to initialize service-wide policies.
       public static void InitializeService(IDataServiceConfiguration config)
       {
           // TODO: set rules to indicate which entity sets and service operations are visible, updatable, etc.
           // Examples:
          config.SetEntitySetAccessRule("*", EntitySetRights.AllRead);
           // config.SetServiceOperationAccessRule("MyServiceOperation", ServiceOperationRights.All);
         //config.DataServiceBehavior.MaxProtocolVersion = DataServiceProtocolVersion.V2;


       }

      protected override MyCustomDataSource CreateDataSource()
       {
           MyCustomDataSource source = new MyCustomDataSource();
           return source;
       }

   }