Code Examples

The first part of this tutorial uses code fragments to walk you through the fundamentals of using the SAAJ API. In this section, you will use some of those code fragments to create applications. First, you will see the program Request.java. Then you will see how to run the programs MyUddiPing.java, HeaderExample.java, DOMExample.java, DOMSrcExample.java, Attachments.java, and SOAPFaultTest.java.

Note: Before you run any of the examples, follow the preliminary setup instructions in Building the Examples.

Request.java

The class Request.java puts together the code fragments used in the section Tutorial and adds what is needed to make it a complete example of a client sending a request-response message. In addition to putting all the code together, it adds import statements, a main method, and a try/catch block with exception handling.

import javax.xml.soap.*;
import javax.xml.namespace.QName;
import java.util.Iterator;
import java.net.URL;

public class Request {
  public static void main(String[] args)  {
    try {
      SOAPConnectionFactory soapConnectionFactory =
        SOAPConnectionFactory.newInstance();
      SOAPConnection connection =
        soapConnectionFactory.createConnection();

      MessageFactory factory =
        MessageFactory.newInstance();
      SOAPMessage message = factory.createMessage();

      SOAPHeader header = message.getSOAPHeader();
      SOAPBody body = message.getSOAPBody();
      header.detachNode();

      QName bodyName = new QName("http://wombat.ztrade.com",
        "GetLastTradePrice", "m");
      SOAPBodyElement bodyElement =
        body.addBodyElement(bodyName);

      QName name = new QName("symbol");
      SOAPElement symbol = 
        bodyElement.addChildElement(name);
      symbol.addTextNode("SUNW");

      URL endpoint = new URL
        ("http://wombat.ztrade.com/quotes");
      SOAPMessage response = 
        connection.call(message, endpoint);

      connection.close();

      SOAPBody soapBody = response.getSOAPBody();

      Iterator iterator = 
        soapBody.getChildElements(bodyName);
      bodyElement = (SOAPBodyElement)iterator.next();
      String lastPrice = bodyElement.getValue();

      System.out.print("The last price for SUNW is ");
      System.out.println(lastPrice);

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

For Request.java to be runnable, the second argument supplied to the call method would have to be a valid existing URI, and this is not true in this case. However, the application in the next section is one that you can run.

MyUddiPing.java

The program MyUddiPing.java is another example of a SAAJ client application. It sends a request to a Universal Description, Discovery and Integration (UDDI) service and gets back the response. A UDDI service is a business registry from which you can get information about businesses that have registered themselves with the registry service. For this example, the MyUddiPing application is accessing a test (demo) version of a UDDI service registry. Because of this, the number of businesses you can get information about is limited. Nevertheless, MyUddiPing demonstrates a request being sent and a response being received.

Setting Up

<INSTALL>//examples/saaj/myuddiping/

In the myuddiping directory, you will find three files and the src directory. The src directory contains one source file, MyUddiPing.java.

The file uddi.properties contains the URL of the destination (a UDDI test registry). To install this registry, follow the instructions in Preliminaries: Getting Access to a Registry. If the Application Server where you install the registry is running on a remote system, open uddi.properties in a text editor and replace localhost with the name of the remote system.

The prepare target creates a directory named build. To invoke the prepare target, you type the following at the command line:

The target named build compiles the source file MyUddiPing.java and puts the resulting .class file in the build directory. So to do these tasks, you type the following at the command line:

Examining MyUddiPing

We will go through the file MyUddiPing.java a few lines at a time, concentrating on the last section. This is the part of the application that accesses only the content you want from the XML message returned by the UDDI registry.

import javax.xml.soap.SOAPConnectionFactory;
import javax.xml.soap.SOAPConnection;
import javax.xml.soap.MessageFactory;
import javax.xml.soap.SOAPMessage;
import javax.xml.soap.SOAPHeader;
import javax.xml.soap.SOAPBody;
import javax.xml.soap.SOAPBodyElement;
import javax.xml.soap.SOAPElement;
import javax.xml.namespace.QName;
import java.net.URL;
import java.util.Properties;
import java.util.Enumeration;
import java.util.Iterator;
import java.io.FileInputStream;

The next few lines begin the definition of the class MyUddiPing, which starts with the definition of its main method. The first thing it does is to check to see whether two arguments were supplied. If they were not, it prints a usage message and exits. The usage message mentions only one argument; the other is supplied by the build.xml target.

public class MyUddiPing {
  public static void main(String[] args) {
    try {
      if (args.length != 2) {
        System.err.println("Usage: asant run " +
          "-Dbusiness-name=<name>");
        System.exit(1);
      }

The following lines create a java.util.Properties object that contains the system properties and the properties from the file uddi.properties, which is in the myuddiping directory.

      Properties myprops = new Properties();
      myprops.load(new FileInputStream(args[0]));

      Properties props = System.getProperties();

      Enumeration propNames = myprops.propertyNames();
      while (propNames.hasMoreElements()) {
        String s = (String) propNames.nextElement(); 
        props.setProperty(s, myprops.getProperty(s));
      }

The next four lines create a SOAPMessage object. First, the code gets an instance of SOAPConnectionFactory and uses it to create a connection. Then it gets an instance of a SOAP 1.1 MessageFactory, using the MessageFactory instance to create a message.

      SOAPConnectionFactory soapConnectionFactory =
        SOAPConnectionFactory.newInstance();
      SOAPConnection connection =
        soapConnectionFactory.createConnection();

      MessageFactory messageFactory =
        MessageFactory.newInstance();
      SOAPMessage message = messageFactory.createMessage();

The next lines of code retrieve the SOAPHeader and SOAPBody objects from the message and remove the header.

      SOAPHeader header = message.getSOAPHeader();
      header.detachNode();
      SOAPBody body = message.getSOAPBody();

The following lines of code create the UDDI find_business message. The first line creates a SOAPBodyElement with a fully qualified name, including the required namespace for a UDDI version 2 message. The next lines add two attributes to the new element: the required attribute generic, with the UDDI version number 2.0, and the optional attribute maxRows, with the value 100. Then the code adds a child element that has the QName object name and adds text to the element by using the method addTextNode. The added text is the business name you will supply at the command line when you run the application.

      SOAPBodyElement findBusiness = 
        body.addBodyElement(new QName(
          "urn:uddi-org:api_v2", "find_business"));
      findBusiness.addAttribute(new QName("generic"), "2.0");
      findBusiness.addAttribute(new QName("maxRows"), "100");

      SOAPElement businessName = 
        findBusiness.addChildElement(new QName("name"));
      businessName.addTextNode(args[1]);

The next line of code saves the changes that have been made to the message. This method will be called automatically when the message is sent, but it does not hurt to call it explicitly.

      message.saveChanges();

      System.out.println("\n---- Request Message ----\n");
      message.writeTo(System.out);

The next line of code creates the java.net.URL object that represents the destination for this message. It gets the value of the property named URL from the system properties.

      URL endpoint = new URL(
        System.getProperties().getProperty("URL"));

Next, the message message is sent to the destination that endpoint represents, which is the UDDI test registry. The call method will block until it gets a SOAPMessage object back, at which point it returns the reply.

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

In the next lines of code, the first line prints a line giving the URL of the sender (the test registry), and the others display the returned message.

      System.out.println("\n\nReceived reply from: " + 
        endpoint);
      System.out.println("\n---- Reply Message ----\n");
      reply.writeTo(System.out);

As interesting as it is to see the XML that is actually transmitted, the XML document format does not make it easy to see the text that is the message's content. To remedy this, the last part of MyUddiPing.java contains code that prints only the text content of the response, making it much easier to see the information you want.

Because the content is in the SOAPBody object, the first step is to access it, as shown in the following line of code.

      SOAPBody replyBody = reply.getSOAPBody();

      System.out.println("\n\nContent extracted from " +
        "the reply message:\n");

To display the content of the message, the code uses the known format of the reply message. First, it gets all the reply body's child elements named businessList:

      Iterator businessListIterator =
        replyBody.getChildElements(new QName(
          "urn:uddi-org:api_v2",
          "businessList"));

The method getChildElements returns the elements in the form of a java.util.Iterator object. You access the child elements by calling the method next on the Iterator object. An immediate child of a SOAPBody object is a SOAPBodyElement object.

We know that the reply can contain only one businessList element, so the code then retrieves this one element by calling the iterator's next method. Note that the method Iterator.next returns an Object, which must be cast to the specific kind of object you are retrieving. Thus, the result of calling businessListIterator.next is cast to a SOAPBodyElement object:

      SOAPBodyElement businessList = 
        (SOAPBodyElement) businessListIterator.next();

The next element in the hierarchy is a single businessInfos element, so the code retrieves this element in the same way it retrieved the businessList. Children of SOAPBodyElement objects and all child elements from this point forward are SOAPElement objects.

      Iterator businessInfosIterator =
        businessList.getChildElements(new QName(
          "urn:uddi-org:api_v2", "businessInfos"));

      SOAPElement businessInfos = 
        (SOAPElement) businessInfosIterator.next();

The businessInfos element contains zero or more businessInfo elements. If the query returned no businesses, the code prints a message saying that none were found. If the query returned businesses, however, the code extracts the name and optional description by retrieving the child elements that have those names. The method Iterator.hasNext can be used in a while loop because it returns true as long as the next call to the method next will return a child element. Accordingly, the loop ends when there are no more child elements to retrieve.

      Iterator businessInfoIterator =
        businessInfos.getChildElements(
          soapFactory.createName("businessInfo", 
            "", "urn:uddi-org:api_v2"));

      if (! businessInfoIterator.hasNext()) {
        System.out.println("No businesses found " +
          "matching the name \"" + args[1] + "\".");
      } else {
        while (businessInfoIterator.hasNext()) {
          SOAPElement businessInfo = (SOAPElement)
            businessInfoIterator.next();

          Iterator nameIterator = 
            businessInfo.getChildElements(new QName(
              "urn:uddi-org:api_v2", "name"));

          while (nameIterator.hasNext()) {
            businessName = 
              (SOAPElement)nameIterator.next();
            System.out.println("Company name: " +
              businessName.getValue());
          }
          Iterator descriptionIterator = 
            businessInfo.getChildElements(new QName(
              "urn:uddi-org:api_v2", "description"));

          while (descriptionIterator.hasNext()) {
            SOAPElement businessDescription = 
              (SOAPElement) descriptionIterator.next();
            System.out.println("Description: " +
              businessDescription.getValue());
          }
          System.out.println("");
        }
      }
    }

Running MyUddiPing

You are now ready to run MyUddiPing. The run target takes two arguments, but you need to supply only one of them. The first argument is the file uddi.properties, which is supplied by a property that is set in build.properties. The other argument is the first letters of the name of the business for which you want to get a description, and you need to supply this argument on the command line. Note that any property set on the command line overrides any value set for that property in the build.xml file.

ant run -Dbusiness-name=the

Content extracted from the reply message:

Company name: The Coffee Break
Description: Purveyor of the finest coffees. Established 1950

The program will not return any results until you have run the examples in Chapter 6

If you want to run MyUddiPing again, you may want to start over by deleting the build directory and the .class file it contains. You can do this by typing the following at the command line:

HeaderExample.java

The example HeaderExample.java, based on the code fragments in the section Adding Attributes, creates a message that has several headers. It then retrieves the contents of the headers and prints them. The example generates either a SOAP 1.1 message or a SOAP 1.2 message, depending on arguments you specify. You will find the code for HeaderExample in the following directory:

<INSTALL>//examples/saaj/headers/src/

Running HeaderExample

To run HeaderExample, you use the file build.xml that is in the directory <INSTALL>//examples/saaj/headers/.

ant run -Dsoap=1.1
asant run -Dsoap=1.2

This command executes the prepare, build, and run targets in the build.xml and targets.xml files.

When you run HeaderExample to generate a SOAP 1.1 message, you will see output similar to the following:

----- Request Message ----

<SOAP-ENV:Envelope 
xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/">
<SOAP-ENV:Header>
<ns:orderDesk xmlns:ns="http://gizmos.com/NSURI" 
SOAP-ENV:actor="http://gizmos.com/orders"/>
<ns:shippingDesk xmlns:ns="http://gizmos.com/NSURI" 
SOAP-ENV:actor="http://gizmos.com/shipping"/>
<ns:confirmationDesk xmlns:ns="http://gizmos.com/NSURI" 
SOAP-ENV:actor="http://gizmos.com/confirmations" 
SOAP-ENV:mustUnderstand="1"/>
<ns:billingDesk xmlns:ns="http://gizmos.com/NSURI" 
SOAP-ENV:actor="http://gizmos.com/billing"/>
</SOAP-ENV:Header><SOAP-ENV:Body/></SOAP-ENV:Envelope>

Header name is {http://gizmos.com/NSURI}orderDesk
Actor is http://gizmos.com/orders
mustUnderstand is false

Header name is {http://gizmos.com/NSURI}shippingDesk
Actor is http://gizmos.com/shipping
mustUnderstand is false

Header name is {http://gizmos.com/NSURI}confirmationDesk
Actor is http://gizmos.com/confirmations
mustUnderstand is true

Header name is {http://gizmos.com/NSURI}billingDesk
Actor is http://gizmos.com/billing
mustUnderstand is false

When you run HeaderExample to generate a SOAP 1.2 message, you will see output similar to the following:

----- Request Message ----

<env:Envelope 
xmlns:env="http://www.w3.org/2003/05/soap-envelope">
<env:Header>
<ns:orderDesk xmlns:ns="http://gizmos.com/NSURI" 
env:role="http://gizmos.com/orders"/>
<ns:shippingDesk xmlns:ns="http://gizmos.com/NSURI" 
env:role="http://gizmos.com/shipping"/>
<ns:confirmationDesk xmlns:ns="http://gizmos.com/NSURI" 
env:mustUnderstand="true" 
env:role="http://gizmos.com/confirmations"/>
<ns:billingDesk xmlns:ns="http://gizmos.com/NSURI" 
env:relay="true" env:role="http://gizmos.com/billing"/>
</env:Header><env:Body/></env:Envelope>

Header name is {http://gizmos.com/NSURI}orderDesk
Role is http://gizmos.com/orders
mustUnderstand is false
relay is false

Header name is {http://gizmos.com/NSURI}shippingDesk
Role is http://gizmos.com/shipping
mustUnderstand is false
relay is false

Header name is {http://gizmos.com/NSURI}confirmationDesk
Role is http://gizmos.com/confirmations
mustUnderstand is true
relay is false

Header name is {http://gizmos.com/NSURI}billingDesk
Role is http://gizmos.com/billing
mustUnderstand is false
relay is true

DOMExample.java and DOMSrcExample.java

The examples DOMExample.java and DOMSrcExample.java show how to add a DOM document to a message and then traverse its contents. They show two ways to do this:

DOMExample.java creates a DOM document and adds it to the body of a message.

DOMSrcExample.java creates the document, uses it to create a DOMSource object, and then sets the DOMSource object as the content of the message's SOAP part.

You will find the code for DOMExample and DOMSrcExample in the following directory:

<INSTALL>//examples/saaj/dom/src/

Examining DOMExample

DOMExample first creates a DOM document by parsing an XML document. The file it parses is one that you specify on the command line.

static Document document;
...
  DocumentBuilderFactory factory =
    DocumentBuilderFactory.newInstance();
  factory.setNamespaceAware(true);
  try {
    DocumentBuilder builder = factory.newDocumentBuilder();
    document = builder.parse( new File(args[0]) );
    ...

Next, the example creates a SOAP message in the usual way. Then it adds the document to the message body:

    SOAPBodyElement docElement = body.addDocument(document);

This example does not change the content of the message. Instead, it displays the message content and then uses a recursive method, getContents, to traverse the element tree using SAAJ APIs and display the message contents in a readable form.

public void getContents(Iterator iterator, String indent) {

  while (iterator.hasNext()) {
    Node node = (Node) iterator.next();
    SOAPElement element = null;
    Text text = null;
    if (node instanceof SOAPElement) {
      element = (SOAPElement)node;
      QName name = element.getElementQName();
      System.out.println(indent + "Name is " + 
        name.toString());
      Iterator attrs = element.getAllAttributesAsQNames();
      while (attrs.hasNext()){
        QName attrName = (QName)attrs.next();
        System.out.println(indent + " Attribute name is " + 
          attrName.toString());
        System.out.println(indent + " Attribute value is " + 
          element.getAttributeValue(attrName));
      }
      Iterator iter2 = element.getChildElements();
      getContents(iter2, indent + " ");
    } else {
      text = (Text) node;
      String content = text.getValue();
      System.out.println(indent + 
        "Content is: " + content);
      }
    }
  }

Examining DOMSrcExample

DOMSrcExample differs from DOMExample in only a few ways. First, after it parses the document, DOMSrcExample uses the document to create a DOMSource object. This code is the same as that of DOMExample except for the last line:

  static DOMSource domSource;
  ...
  try {
    DocumentBuilder builder = factory.newDocumentBuilder();
    Document document = builder.parse(new File(args[0]));
    domSource = new DOMSource(document);
    ...

Then, after DOMSrcExample creates the message, it does not get the header and body and add the document to the body, as DOMExample does. Instead, DOMSrcExample gets the SOAP part and sets the DOMSource object as its content:

// Create a message
SOAPMessage message = messageFactory.createMessage();

// Get the SOAP part and set its content to domSource
SOAPPart soapPart = message.getSOAPPart();
soapPart.setContent(domSource);

The example then uses the getContents method to obtain the contents of both the header (if it exists) and the body of the message.

The most important difference between these two examples is the kind of document you can use to create the message. Because DOMExample adds the document to the body of the SOAP message, you can use any valid XML file to create the document. But because DOMSrcExample makes the document the entire content of the message, the document must already be in the form of a valid SOAP message, and not just any XML document.

Running DOMExample and DOMSrcExample

To run DOMExample and DOMSrcExample, you use the file build.xml that is in the directory <INSTALL>//examples/saaj/dom/. This directory also contains several sample XML files you can use:

domsrc1.xml, an example that has a SOAP header (the contents of the HeaderExample output) and the body of a UDDI query

domsrc2.xml, an example of a reply to a UDDI query (specifically, some sample output from the MyUddiPing example), but with spaces added for readability

uddimsg.xml, similar to domsrc2.xml except that it is only the body of the message and contains no spaces

slide.xml, another file that consists only of a body but that contains spaces

You can use any of these four files when you run DOMExample. To run DOMExample, use a command like the following:

ant run-dom -Dxml-file=uddimsg.xml

When you run DOMExample using the file uddimsg.xml, you will see output that begins like the following:

Running DOMExample.
Name is {urn:uddi-org:api_v2}businessList
Attribute name is generic
Attribute value is 2.0
Attribute name is operator
Attribute value is www.ibm.com/services/uddi
Attribute name is truncated
Attribute value is false
Attribute name is xmlns
Attribute value is urn:uddi-org:api_v2
...

You can use either domsrc1.xml or domsrc2.xml to run DOMSrcExample. To run DOMSrcExample, use a command like the following:

ant run-domsrc -Dxml-file=domsrc2.xml

When you run DOMSrcExample using the file domsrc2.xml, you will see output that begins like the following:

run-domsrc:
  Running DOMSrcExample.
  Body contents:
  Content is: 

  Name is {urn:uddi-org:api_v2}businessList
   Attribute name is generic
   Attribute value is 2.0
   Attribute name is operator
   Attribute value is www.ibm.com/services/uddi
   Attribute name is truncated
   Attribute value is false
   Attribute name is xmlns
   Attribute value is urn:uddi-org:api_v2
   ...

If you run DOMSrcExample with the file uddimsg.xml or slide.xml, you will see runtime errors.

Attachments.java

<INSTALL>//examples/saaj/attachments/src/

Attachments first creates a message in the usual way. It then creates an AttachmentPart for the text attachment:

AttachmentPart attachment1 = message.createAttachmentPart();

After it reads input from a file into a string named stringContent, it sets the content of the attachment to the value of the string and the type to text/plain and also sets a content ID.

attachment1.setContent(stringContent, "text/plain");
attachment1.setContentId("attached_text");

message.addAttachmentPart(attachment1);

The example uses a javax.activation.DataHandler object to hold a reference to the graphic that constitutes the second attachment. It creates this attachment using the form of the createAttachmentPart method that takes a DataHandler argument.

// Create attachment part for image
URL url = new URL("file:///../xml-pic.jpg"); 
DataHandler dataHandler = new DataHandler(url); 
AttachmentPart attachment2 = 
  message.createAttachmentPart(dataHandler); 
attachment2.setContentId("attached_image"); 

message.addAttachmentPart(attachment2);

The example then retrieves the attachments from the message. It displays the contentId and contentType attributes of each attachment and the contents of the text attachment.

Running Attachments

To run Attachments, you use the file build.xml that is in the directory <INSTALL>//examples/saaj/attachments/.

ant run -Dfile=path_name

Specify any text file as the path_name argument. The attachments directory contains a file named addr.txt that you can use:

ant run -Dfile=addr.txt

When you run Attachments using this command line, you will see output like the following:

Running Attachments.
Attachment attached_text has content type text/plain
Attachment contains:
Update address for Sunny Skies, Inc., to 
10 Upbeat Street
Pleasant Grove, CA 95439

Attachment attached_image has content type image/jpeg

SOAPFaultTest.java

<INSTALL>//examples/saaj/fault/src/

Running SOAPFaultTest

To run SOAPFaultTest, you use the file build.xml that is in the directory <INSTALL>//examples/saaj/fault/.

Like HeaderExample, this example contains code that allows you to generate either a SOAP 1.1 or a SOAP 1.2 message.

ant run -Dsoap=1.1
asant run -Dsoap=1.2

When you run SOAPFaultTest to generate a SOAP 1.1 message, you will see output like the following (line breaks have been inserted in the message for readability):

Here is what the XML message looks like:

<SOAP-ENV:Envelope 
xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/">
<SOAP-ENV:Header/><SOAP-ENV:Body>
<SOAP-ENV:Fault><faultcode>SOAP-ENV:Client</faultcode>
<faultstring>Message does not have necessary info</faultstring>
<faultactor>http://gizmos.com/order</faultactor>
<detail>
<PO:order xmlns:PO="http://gizmos.com/orders/">
Quantity element does not have a value</PO:order>
<PO:confirmation xmlns:PO="http://gizmos.com/confirm">
Incomplete address: no zip code</PO:confirmation>
</detail></SOAP-ENV:Fault>
</SOAP-ENV:Body></SOAP-ENV:Envelope>

SOAP fault contains: 
 Fault code = {http://schemas.xmlsoap.org/soap/envelope/}Client
 Local name = Client
 Namespace prefix = SOAP-ENV, bound to 
http://schemas.xmlsoap.org/soap/envelope/
 Fault string = Message does not have necessary info
 Fault actor = http://gizmos.com/order
 Detail entry = Quantity element does not have a value
 Detail entry = Incomplete address: no zip code

When you run SOAPFaultTest to generate a SOAP 1.2 message, the output looks like this:

Here is what the XML message looks like:

<env:Envelope 
xmlns:env="http://www.w3.org/2003/05/soap-envelope">
<env:Header/><env:Body>
<env:Fault>
<env:Code><env:Value>env:Sender</env:Value></env:Code>
<env:Reason><env:Text xml:lang="en-US">
Message does not have necessary info
</env:Text></env:Reason>
<env:Role>http://gizmos.com/order</env:Role>
<env:Detail>
<PO:order xmlns:PO="http://gizmos.com/orders/">
Quantity element does not have a value</PO:order>
<PO:confirmation xmlns:PO="http://gizmos.com/confirm">
Incomplete address: no zip code</PO:confirmation>
</env:Detail></env:Fault>
</env:Body></env:Envelope>

SOAP fault contains: 
 Fault code = {http://www.w3.org/2003/05/soap-envelope}Sender
 Local name = Sender
 Namespace prefix = env, bound to 
http://www.w3.org/2003/05/soap-envelope
 Fault reason text = Message does not have necessary info
 Fault role = http://gizmos.com/order
 Detail entry = Quantity element does not have a value
 Detail entry = Incomplete address: no zip code