WSJ-Journal

Document-Based Web Services Using JAXM by Nikhil Patil
WSJ Vol 03 Issue 4 - pg.33
	


Listing 1

	try
	{
		pcf = ProviderConnectionFactory.newInstance();
		pc = pcf.createConnection();
	}
	catch (SOAPException e)
	{
		throw new ServletException(e);
	}

Listing 2

	String[] supportedProfiles = metaData.getSupportedProfiles();
	String profile = null;
	for(int i=0; i < supportedProfiles.length; i++)
	{
		if(supportedProfiles[i].equals("soaprp"))
		{
			profile = supportedProfiles[i];
			break;
		}
	}
	
	
	
Listing 3:

	Method of ControllerServlet to Invoke A JAXM Service using a JAXM Provider.

	private void submitBill(HttpServletRequest request) throws ServletException
	{
		
		try
		{
           // Create a message factory.
	    	if (mf == null)
	    	{
	    		ProviderMetaData metaData = null;
	    		try
	    		{
	        		metaData = pc.getMetaData();
	    		}
	    		catch (SOAPException e)
	    		{
	    			throw new ServletException(e);
	    		}
	    		
	// Find the SOAP-RP profie and create a MessageFactory that supports
	// SOAP-RP messages.
	        	String[] supportedProfiles = metaData.getSupportedProfiles();
	        	String profile = null;
	        	for(int i=0; i < supportedProfiles.length; i++)
	        	{
	  	    		if(supportedProfiles[i].equals("soaprp"))
	  	    		{
		        		profile = supportedProfiles[i];
		   	 			break;
		    		}
	        	}            
          		mf = pc.createMessageFactory(profile);
	    	}
            
	     	// Create a SOAP-RP message from the message factory.
   	SOAPRPMessageImpl msg = (SOAPRPMessageImpl)mf.createMessage();
	        // Set the end point.
	        msg.setTo(new  Endpoint(submitBillURL));
				
			SOAPPart sp = msg.getSOAPPart();
			SOAPEnvelope envelope = sp.getEnvelope();
			SOAPBody bdy = envelope.getBody();
	
			// Add a root element "bill" to the soap message.
			SOAPBodyElement billElement =
			bdy.addBodyElement(envelope.createName("bill"));
	
			// Add the name of the company to the message
			String company = request.getParameter("company");
			billElement.addChildElement(envelope.createName
("company")).addTextNode(company);
			
			// Add the name of the company to the message
			String customer = request.getParameter("customer");
			billElement.addChildElement(envelope.createName
("customer")).addTextNode(customer);
			
			// Add the name of the company to the message
			String hours = request.getParameter("hours");
			billElement.addChildElement(envelope.createName
			("hours")).addTextNode(hours);
	
			// Send the message
			msg.writeTo(System.out);
			pc.send(msg);

		}
		catch (Exception se)
		{
			se.printStackTrace();
		}

	}
	
	
Listing 4: Bill information as a SOAP message.

<?xml version="1.0" encoding="UTF-8"?>
<soap-env:Envelope xmlns:soap-env=
"http://schemas.xmlsoap.org/soap/envelope/">
	<soap-env:Header>
		<m:path xmlns:m="http://schemas.xmlsoap.org/rp">
			<m:to>http://xyz.acme.com/processbill</m:to>
			<m:id>2ea82d39-b48e-47f2-b85d-d94ad2cbce03
			</m:id><m:fwd/><m:rev/>
		</m:path>
	</soap-env:Header>
	<soap-env:Body>
		<bill>
			<company>Cysive</company>
			<customer>Tom Jones</customer>
			<hours>2</hours>
		</bill>
	</soap-env:Body>
</soap-env:Envelope>

Listing 5: Synchronous JAXM Service.

package acme;

import javax.xml.messaging.JAXMServlet;
import javax.xml.messaging.OnewayListener;
import javax.xml.soap.*;
import java.util.*;

/**
 * Asynchronous JAXM Service.
 */
public class BillProcessingServlet
	extends JAXMServlet
	implements OnewayListener
{

	/**
	 * Extracts billing information from the SOAP message and updates
	 * the billing system.
	 * @param message SOAP message containing billing information.
	 */
	public void onMessage(SOAPMessage message)
	{
		try
		{
			
			SOAPPart part = message.getSOAPPart();
			SOAPEnvelope envelope = part.getEnvelope();
			SOAPBody body = envelope.getBody();
			
	// Extract information about the bill from the SOAPMessage.
		Iterator itr = body.getChildElements(envelope.createName("bill"));
			if (itr.hasNext())
			{
		SOAPElement element = (SOAPElement)itr.next();
				Bill bill = new Bill();
				
				// Extract Customer Name.
String customerName = extractData(element.getChildElements
(envelope.createName("customer")));
				bill.setCustomerName(customerName);
				
				// Extract Company Name.
String company = extractData(element.getChildElements
(envelope.createName("company")));
				bill.setCompany(company);
				
				// Extract Hours.
String hours = extractData(element.getChildElements
(envelope.createName("hours")));
				bill.setHours(Double.parseDouble(hours));
				
				// Process the Bill.
				BillingSystem.getInstance().process(bill);
			}
			
		}
		catch (SOAPException se)
		{
			se.printStackTrace();
		}
	}
	
	// Extracts the text value of a XML element.
	private String extractData(Iterator itr)
	{
		if (itr.hasNext())
		{
			SOAPElement element = (SOAPElement)itr.next();
			return element.getValue();
		}
		else
		{
			return "";
		}
	}

}

Listing 6:

	Code Snippet from Controller Servlet to invoke a Synchronous JAXM Client.

	private void findBills(HttpServletRequest request,
					HttpServletResponse response
					)
			throws IOException, ServletException
	{
		String company = request.getParameter("company");
		if (company == null || company.trim().equals(""))
		{
	request.setAttribute("error","Company Name cannot be null or empty");
			sendResponse("/search.jsp", request, response);
		}
		else
		{
			try
		 	{
		 		// Create a SOAPMessage
SOAPMessage message = MessageFactory.newInstance().createMessage();
 		SOAPPart part = message.getSOAPPart();
		SOAPEnvelope envelope = part.getEnvelope();
    	SOAPBody body = envelope.getBody();
					
SOAPBodyElement bodyElement = body.addBodyElement
(envelope.createName("findBills"));
bodyElement.addChildElement(envelope.createName("company")).addTextNode(company);
					
				// Create a SOAP Connection
SOAPConnection connection =
SOAPConnectionFactory.newInstance().createConnection();
java.net.URL endpoint = new java.net.URL("http://localhost:8080/messaging/findBills");
					
				// Send the message
				message.writeTo(System.out);
	SOAPMessage responseMessage = connection.call(message, endpoint);
	responseMessage.writeTo(response.getOutputStream());
		 	}
		 	catch (Exception se)
		 	{
		 		throw new ServletException(se);
		 	}
		 }
	}
	
Listing 7:

Synchronous JAXM Service which provides billing information.

package acme;

import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.xml.messaging.*;
import javax.xml.soap.*;
import java.util.*;

/**
 * Synchronous JAXM Service.
 */
public class BillingInformationServlet
	extends JAXMServlet
	implements ReqRespListener
{
	MessageFactory factory = null;

	/**
	 * Returns a SOAPMessage containing a list of bills for a given
	 * company.
	 * @param message Incoming SOAPMessage containing the company name.
	 * @return A SOAPMessage containing a list of bills.
	 */
	public SOAPMessage onMessage(SOAPMessage message)
	{
		try
		{
			// Extract the name of the company.
			String companyName = extractCompanyName(message);
					
// Search the billing system for a collection of bills for a given company.
		Collection bills = BillingSystem.getInstance().getBills(companyName);
			
// Build and return a SOAPMessage from the collection of bills.
			return buildMessage(bills);
			
		}
		catch (SOAPException ex)
		{
// Catch the exception and return a SOAPMessage with a SOAPFault.
			ex.printStackTrace();
			return buildFault(ex);
		}
	}

	/**
	 * Initializes the servlet.
	 * @param config Instance of ServletConfig.
	 * @throws javax.servlet.ServletException thrown if there is an error in intialization.
	 */
	public void init(ServletConfig config) throws ServletException
	{
		super.init(config);
		try
		{
			factory = MessageFactory.newInstance();
		}
		catch (SOAPException se)
		{
			throw new ServletException(se);
		}
	}
	
	/**
	 *  Extracts the name of the company
	 */
private String extractCompanyName(SOAPMessage message) throws SOAPException
	{
		SOAPPart part = message.getSOAPPart();
		SOAPEnvelope envelope = part.getEnvelope();
		SOAPBody body = envelope.getBody();
			
		// Extract the company Name
		java.util.Iterator itr = body.getChildElements
		(envelope.createName("findBills"));
		if (itr.hasNext())
		{
	SOAPElement element = (SOAPElement)itr.next();
Iterator children = element.getChildElements(envelope.createName("company"));
				return extractData(children);
				
		}
		return null;
	}
	
	/**
	 *  Returns a text value of a certain element.
	 */
	private String extractData(Iterator itr)
	{
		if (itr.hasNext())
		{
			SOAPElement element = (SOAPElement)itr.next();
			return element.getValue();
		}
		else
		{
			return "";
		}
	}
	
	// Builds a SOAPMessage from a collection of bills.
	private SOAPMessage buildMessage(Collection collection)
	throws SOAPException
	{
		SOAPMessage message = factory.createMessage();
		SOAPPart sp = message.getSOAPPart();
		SOAPEnvelope envelope = sp.getEnvelope();
		SOAPBody bdy = envelope.getBody();

		// Add the root element "bills" to the SOAPBody.
		SOAPBodyElement billsElement = bdy.addBodyElement
		(envelope.createName("bills"));
				
		Iterator itr = collection.iterator();
		while (itr.hasNext())
		{
			Bill bill = (Bill)itr.next();
			
	// Add information about the bill to the root element "bills".
SOAPElement billElement = billsElement.addChildElement(envelope.createName("bill"));
			billElement.addChildElement(envelope.createName
("company")).addTextNode(bill.getCompany());
			billElement.addChildElement(envelope.createName
("customer")).addTextNode(bill.getCustomerName());
			
			String hours =	String.valueOf(bill.getHours());
			billElement.addChildElement(envelope.createName
			("hours")).addTextNode(hours);
			
			String rate =	String.valueOf(bill.getHourlyRate());
			billElement.addChildElement(envelope.createName
			("rate")).addTextNode(rate);
			
			String total =	String.valueOf(bill.getAmount());
			billElement.addChildElement(envelope.createName
			("total")).addTextNode(total);
		}
		
		return message;
	}
	
	// Returns SOAPMessage containing a SOAPFault.
	private SOAPMessage buildFault(Exception ex)
	{
		try
		{
			SOAPMessage message = factory.createMessage();
			SOAPPart sp = message.getSOAPPart();
			SOAPEnvelope envelope = sp.getEnvelope();
			SOAPBody bdy = envelope.getBody();
			SOAPFault fault = bdy.addFault();
			fault.setFaultString(ex.getMessage());
			return message;
		}
		catch (SOAPException se)
		{
			se.printStackTrace();
			return null;
		}		
	}
}


Listing 8:

JAXM request for searching for bills.

<?xml version="1.0" encoding="UTF-8"?>
<soap-env:Envelope xmlns:soap-env=
"http://schemas.xmlsoap.org/soap/envelope/">
	<soap-env:Header/>
	<soap-env:Body>
		<findBills>
			<company>Cysive</company>
		</findBills>
	</soap-env:Body>
</soap-env:Envelope>


JAXM Response for the search request.

<?xml version="1.0" encoding="UTF-8" ?>
<soap-env:Envelope xmlns:soap-env=
"http://schemas.xmlsoap.org/soap/envelope/">
	<soap-env:Header />
	<soap-env:Body>
		<bills>
			<bill>
  				<company>Cysive</company>
  				<customer>Tom Jones</customer>
  				<hours>2.0</hours>
  				<rate>50.0</rate>
  				<total>100.0</total>
  			</bill>
 		</bills>
  	</soap-env:Body>
</soap-env:Envelope>