XML Reference Guide

Sending SOAP messages using Java is fairly straightforward. The SOAP with Attachments API for Java (SAAJ) enables you to create a SOAP message as an XML object, and then send it to a particular service URL, receiving a SOAP message in response.

Consider this SOAP message:

<?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>
       <req:getTemp xmlns:req="http://www.example.com/checkWeather/">
           <zipcode>02134</zipcode>
       </req:getTemp>
   </SOAP-ENV:Body>
</SOAP-ENV:Envelope>

We can send it to a weather service using a simple application. First, we need to create the message object itself.

import javax.xml.soap.*; 
import javax.xml.transform.*;
import java.io.FileInputStream;
import javax.xml.transform.stream.*;
import org.w3c.dom.*;

public class SendSOAP {
    
   public static void main(String args[]) {
        
      try {
      
         //Next, create the actual message
         MessageFactory messageFactory = MessageFactory.newInstance();
         SOAPMessage message = messageFactory.createMessage();
         
         //Create objects for the message parts            
         SOAPPart soapPart = message.getSOAPPart();
         SOAPEnvelope envelope = soapPart.getEnvelope();
         SOAPBody body = envelope.getBody();
     
     } catch (Exception e){
         e.printStackTrace();
     }
  }
}

In this case, we first create the message itself, using a MessageFactory. The message itself consists of the headers and the content, with the content as part of the SOAPPart. We can then get a reference to the envelope, and then to the body. Once we've got that, we can add elements to the body itself to create the actual message:

...
         SOAPPart soapPart = message.getSOAPPart();
         SOAPEnvelope envelope = soapPart.getEnvelope();
         SOAPBody body = envelope.getBody();

         SOAPElement bodyElement = 
                  body.addChildElement(envelope.createName("getTemp", "req", 
                                    "http://www.example.com/checkWeather/"));
         bodyElement.addChildElement("zipcode").addTextNode("02134");
         message.saveChanges();
     
     } catch(Exception e) {
          System.out.println(e.getMessage());
     }
  }
}

Alternatively, we could have populated the message from a file, as in:

...
      StreamSource preppedMsgSrc = 
            new StreamSource(new FileInputStream("prepped.msg")); 
      soapPart.setContent(preppedMsgSrc);
...

Once we've got the message created, we can create the connection and send the message:

...
        message.saveChanges();

        //First create the connection
        SOAPConnectionFactory soapConnFactory = 
                           SOAPConnectionFactory.newInstance();
        SOAPConnection connection = 
                           soapConnFactory.createConnection();
         
        SOAPMessage reply = connection.call(message, 
                   "http://www.example.com/checkWeather/rpcrouter");


        connection.close();
            
     } catch(Exception e) {
        System.out.println(e.getMessage());
     }
  }
}

Notice that the call() method returns a SOAPMessage object, which you can manipulate just as you manipulated the original message:

...
        SOAPMessage reply = connection.call(message, destination);

        SOAPEnvelope replyEnvelope = message.getSOAPPart().getEnvelope();
        Node replyHeaderElement = replyEnvelope.getFirstChild();
        Node replyBodyElement = replyHeaderElement.getNextSibling();
        System.out.println(replyBodyElement.getNodeName());
...

You can also use the getContent() method to extract the content of the SOAP message into a Source object you can use in an XSLT transformation:

...
        SOAPMessage reply = connection.call(message, 
                     "http://www.example.com/checkWeather/rpcrouter");

        TransformerFactory transformerFactory = 
                           TransformerFactory.newInstance();
        Transformer transformer = 
                        transformerFactory.newTransformer();

        Source sourceContent = reply.getSOAPPart().getContent();
        StreamResult result = new StreamResult(System.out);
        transformer.transform(sourceContent, result);

         connection.close();
            
     } catch(Exception e) {
         System.out.println(e.getMessage());
     }
   }
}

You can manipulate the stream directly, but if you're using Java, the SAAJ package makes it much easier to deal with sending a SOAP message and receiving the reply.