bookpriceservice.java

java web services how to program

// Fig. 16.20: BookPriceService.java.
// Class BookPriceService invokes the Best Book Price Web service.
package jws1casestudy.clients.j2me;

// import J2ME classes
import java.util.*;

// import Enhydra XML and SOAP packages
import org.ksoap.*;
import org.ksoap.transport.*;
import org.kobjects.serialization.*;

public class BookPriceService {

   // URL of Best Book Price Web service
   private final static String SERVICE_URL = 
      "http://localhost:8080/axis/services/BestBookPrice";

   // namespace that Best Book Price Web service uses
   private final static String NAMESPACE =
      "http://common.pricefinder.jws1casestudy.PriceQuote";

   // invoke Best Book Price Web service
   public PriceQuote getBestPrice( String isbn )
   {
      // invoke Web service and convert result to PriceQuote
      try {

         // establish HTTP connection to Web-service URL
         HttpTransport httpTransport = 
            new HttpTransport( SERVICE_URL, "" );

         // create SOAP request to invoke Best Book Price service
         SoapObject request = 
            new SoapObject( NAMESPACE, "getBestPrice" );

         // include ISBN as parameter in SOAP request
         request.addProperty( "isbn", isbn );

         // invoke Best Book Price Web service
         SoapObject response = ( SoapObject )
            httpTransport.call( request );

         // obtain price from response
         SoapPrimitive price = 
            ( SoapPrimitive ) response.getProperty( "price" );

         // obtain ISBN from response
         String ISBN = ( String ) response.getProperty( "isbn" );

         // obtain storeID from response
         Integer storeID = 
            ( Integer ) response.getProperty( "storeID" );

         // obtain storeDescription from response
         String storeDescription = 
            ( String ) response.getProperty( "storeDescription" );

         // create PriceQuote from response values
         PriceQuote priceQuote = new PriceQuote( 
            price.toString(), ISBN, storeID.intValue(), 
            storeDescription );

         return priceQuote;
      }

      // handle exception in Web-service invocation
      catch ( SoapFault fault ) {
         fault.printStackTrace();
         return null;
      }

      // handle exception in sending or receiving SOAP message
      catch ( java.io.IOException ioException ) {
         ioException.printStackTrace();
         return null;
      }

      // handle exception in PriceQuote cast operation
      catch ( ClassCastException exception ) {
         exception.printStackTrace();
         return null;
      }

   } // end method getBestPrice

} // end class BookPriceService