SOAP request to WebService with java

Question

I'm a bit confused about how to make a request to a webservice via java.

For now the only thing that I've understand is that webservices uses xml structured messages, but still I didn't quite understood how to structure my request.

<soap:Envelope xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/">
  <soap:Body>
    <getProductDetails xmlns="http://magazzino.example.com/ws">
      <productId>827635</productId>
    </getProductDetails>
  </soap:Body>
</soap:Envelope>

Basically I've to send 2 parameters to the web service and in return I expect two other parameters.

I guess there are some jars that can do most of the job, but I didn't find any online. Can someone please explain me the basis?

Answer 1

A SOAP request is an XML file consisting of the parameters you are sending to the server.

The SOAP response is equally an XML file, but now with everything the service wants to give you.

Basically the WSDL is a XML file that explains the structure of those two XML.

---

To implement simple SOAP clients in Java, you can use the SAAJ framework (it is shipped with JSE 1.6 and above):

SOAP with Attachments API for Java (SAAJ) is mainly used for dealing directly with SOAP Request/Response messages which happens behind the scenes in any Web Service API. It allows the developers to directly send and receive soap messages instead of using JAX-WS.

See below a working example (run it!) of a SOAP web service call using SAAJ. It calls this web service .

import javax.xml.soap.*;

public class SOAPClientSAAJ {

    // SAAJ - SOAP Client Testing
    public static void main(String args[]) {
        /*
            The example below requests from the Web Service at:
             http://www.webservicex.net/uszip.asmx?op=GetInfoByCity


            To call other WS, change the parameters below, which are:
             - the SOAP Endpoint URL (that is, where the service is responding from)
             - the SOAP Action

            Also change the contents of the method createSoapEnvelope() in this class. It constructs
             the inner part of the SOAP envelope that is actually sent.
         */
        String soapEndpointUrl = "http://www.webservicex.net/uszip.asmx";
        String soapAction = "http://www.webserviceX.NET/GetInfoByCity";

        callSoapWebService(soapEndpointUrl, soapAction);
    }

    private static void createSoapEnvelope(SOAPMessage soapMessage) throws SOAPException {
        SOAPPart soapPart = soapMessage.getSOAPPart();

        String myNamespace = "myNamespace";
        String myNamespaceURI = "http://www.webserviceX.NET";

        // SOAP Envelope
        SOAPEnvelope envelope = soapPart.getEnvelope();
        envelope.addNamespaceDeclaration(myNamespace, myNamespaceURI);

            /*
            Constructed SOAP Request Message:
            <SOAP-ENV:Envelope xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/" xmlns:myNamespace="http://www.webserviceX.NET">
                <SOAP-ENV:Header/>
                <SOAP-ENV:Body>
                    <myNamespace:GetInfoByCity>
                        <myNamespace:USCity>New York</myNamespace:USCity>
                    </myNamespace:GetInfoByCity>
                </SOAP-ENV:Body>
            </SOAP-ENV:Envelope>
            */

        // SOAP Body
        SOAPBody soapBody = envelope.getBody();
        SOAPElement soapBodyElem = soapBody.addChildElement("GetInfoByCity", myNamespace);
        SOAPElement soapBodyElem1 = soapBodyElem.addChildElement("USCity", myNamespace);
        soapBodyElem1.addTextNode("New York");
    }

    private static void callSoapWebService(String soapEndpointUrl, String soapAction) {
        try {
            // Create SOAP Connection
            SOAPConnectionFactory soapConnectionFactory = SOAPConnectionFactory.newInstance();
            SOAPConnection soapConnection = soapConnectionFactory.createConnection();

            // Send SOAP Message to SOAP Server
            SOAPMessage soapResponse = soapConnection.call(createSOAPRequest(soapAction), soapEndpointUrl);

            // Print the SOAP Response
            System.out.println("Response SOAP Message:");
            soapResponse.writeTo(System.out);
            System.out.println();

            soapConnection.close();
        } catch (Exception e) {
            System.err.println("\nError occurred while sending SOAP Request to Server!\nMake sure you have the correct endpoint URL and SOAPAction!\n");
            e.printStackTrace();
        }
    }

    private static SOAPMessage createSOAPRequest(String soapAction) throws Exception {
        MessageFactory messageFactory = MessageFactory.newInstance();
        SOAPMessage soapMessage = messageFactory.createMessage();

        createSoapEnvelope(soapMessage);

        MimeHeaders headers = soapMessage.getMimeHeaders();
        headers.addHeader("SOAPAction", soapAction);

        soapMessage.saveChanges();

        /* Print the request message, just for debugging purposes */
        System.out.println("Request SOAP Message:");
        soapMessage.writeTo(System.out);
        System.out.println("\n");

        return soapMessage;
    }

}

Answer 2

When the WSDL is available, it is just two steps you need to follow to invoke that web service.

Step 1: Generate the client side source from a WSDL2Java tool

Step 2: Invoke the operation using:

YourService service = new YourServiceLocator();
Stub stub = service.getYourStub();
stub.operation();

If you look further, you will notice that the Stub class is used to invoke the service deployed at the remote location as a web service. When invoking that, your client actually generates the SOAP request and communicates. Similarly the web service sends the response as a SOAP. With the help of a tool like Wireshark, you can view the SOAP messages exchanged.

However since you have requested more explanation on the basics, I recommend you to refer here and write a web service with it's client to learn it further.

Answer 3

I have come across other similar question here . Both of above answers are perfect, but here trying to add additional information for someone looking for SOAP1.1 , and not SOAP1.2 .

Just change one line code provided by @acdcjunior, use SOAPMessageFactory1_1Impl implementation, it will change namespace to xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/", which is SOAP1.1 implementation.

Change callSoapWebService method first line to following.

SOAPMessage soapMessage = SOAPMessageFactory1_1Impl.newInstance().createMessage();

I hope it will be helpful to others.

Answer 4

if you have WSDL, You can create a new soap request in SoapUI with that WSDL file.
It would automatically generate the Structure/XML for input request.

Here is some simple version of Java code you can use to call Soap service if you have the input request xml from SoapUI:

import java.io.BufferedReader;
import java.io.DataOutputStream;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;

public class SimpleSoapClient {

public static void main(String args[]) throws IOException {
        
    String address="Hyderabad";

    /* place your xml request from soap ui below with necessary changes in parameters*/
    
    String xml="<soapenv:Envelope xmlns:soapenv=\"http://schemas.xmlsoap.org/soap/envelope/\" xmlns:ws=\"http://www.YourUrlAsPerWsdl.com/\">\r\n" + 
                 "   <soapenv:Header/>\r\n" + 
                 "   <soapenv:Body>\r\n" + 
                 "      <ws:callRest>\r\n" + 
                 "         <name>"+"Hello"+"</name>\r\n" + 
                 "         <address>"+address+"</address>\r\n" + 
                 "      </ws:callRest>\r\n" + 
                 "   </soapenv:Body>\r\n" + 
                 "</soapenv:Envelope>";
            String responseF=callSoapService(xml);
            System.out.println(responseF);
    }
    

}

static String callSoapService(String soapRequest) {
    try {
     String url = "https://gogle.com/service/hello"; // replace your URL here
     URL obj = new URL(url);
     HttpURLConnection con = (HttpURLConnection) obj.openConnection();
     
     // change these values as per soapui request on top left of request, click on RAW, you will find all the headers
     con.setRequestMethod("POST");
     con.setRequestProperty("Content-Type","text/xml; charset=utf-8"); 
     con.setDoOutput(true);
     DataOutputStream wr = new DataOutputStream(con.getOutputStream());
     wr.writeBytes(soapRequest);
     wr.flush();
     wr.close();
     String responseStatus = con.getResponseMessage();
     System.out.println(responseStatus);
     BufferedReader in = new BufferedReader(new InputStreamReader(
     con.getInputStream()));
     String inputLine;
     StringBuffer response = new StringBuffer();
     while ((inputLine = in.readLine()) != null) {
         response.append(inputLine);
     }
     in.close();
     
     // You can play with response which is available as string now:
     String finalvalue= response.toString();
     
     // or you can parse/substring the required tag from response as below based your response code
     finalvalue= finalvalue.substring(finalvalue.indexOf("<response>")+10,finalvalue.indexOf("</response>")); */
     
     return finalvalue;
     } 
    catch (Exception e) {
        return e.getMessage();
    }   
}

}