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<title>Axis 2.0 User's Guide</title> | |
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<meta name="CHANGEDBY" content="Chamikara Jayalath"> | |
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<h1 align="center"><a name="_Toc96697849"></a>Axis 2.0 User's Guide</h1> | |
<h2>Contents</h2> | |
<ul> | |
<li><p><a href="#Introduction">Introduction</a></p> | |
</li> | |
<li><p><a href="#What_is_Axis_2_0__">What is Axis 2.0 ?</a></p> | |
</li> | |
<li><p><a href="#Web_Services_Using_Axis2">Web Services Using Axis2</a></p> | |
</li> | |
<li><p><a href="#Web_Service_Clients_Using_Axis2">Web Service Clients Using Axis2</a></p> | |
</li> | |
<li><p><a href="#Modules">Modules</a></p> | |
</li> | |
<li><p><a href="#Other_Samples">Other Samples</a></p> | |
</li> | |
<li><p><a href="#Tools">Tools</a></p> | |
</li> | |
<li><p><a href="#Advanced_Topics">Advanced Topics</a></p> | |
</li> | |
</ul> | |
<p><br> | |
<br> | |
</p> | |
<h2><a name="_Toc96698076"></a><a name="Introduction"></a>Introduction</h2> | |
<p>Welcome to Axis 2.0, the next generation of Apache Axis !!! This User | |
Guide will help you to understand what you will get from Axis 2.0 and how to | |
get started. We hope you will benefit from the power of Axis 2.0.</p> | |
<h2>Attention</h2> | |
<ul> | |
<li><p style="margin-bottom: 0in">This User Guide is written based on the | |
Axis2 binary distribution, the Binary distribution can be created from | |
the source distribution using the maven goal <code>$maven | |
dist-bin</code></p> | |
</li> | |
<li><p>Before we start, its highly recommended to read <a | |
href="http://ws.apache.org/axis/java/user-guide.html">Axis 1.x User's | |
guide </a>, if you are new to Axis.</p> | |
</li> | |
</ul> | |
<h2><a name="_Toc96698077"></a><a name="What_is_Axis_2_0__"></a>What is Axis 2.0 ?</h2> | |
<p>Axis 2.0 is the next generation of Apache Axis. In late August 2004, | |
during the Axis Summit held in Colombo, Sri Lanka, a new architecture was | |
introduced to have a much more flexible, efficient and configurable Axis. | |
Even though the architecture is new, some of the well established concepts | |
from Axis 1.x, like handlers are preserved in Axis 2.0 also. Axis 2.0 comes | |
with lots of new features, enhancements and new industry specification | |
implementations.</p> | |
<p>After months of continued discussion and coding effort in this direction, | |
Axis 2.0 now delivers the following key features:</p> | |
<ul> | |
<li><p style="margin-bottom: 0in"><strong>Speed</strong>. Axis uses its own | |
object model and StAX (streaming) parsing to achieve significantly | |
greater speed than earlier versions of Apache AXIS.</p> | |
</li> | |
<li><p style="margin-bottom: 0in"><strong>Low memory foot print</strong>. | |
Axis 2.0 was designed ground-up keeping low memory foot print in mind.</p> | |
</li> | |
<li><p style="margin-bottom: 0in"><strong>AXIOM</strong>. Axis 2.0 comes | |
with its own light-weight object model, AXIOM, for message processing | |
which is extensible, high performance and developer convenient</p> | |
</li> | |
<li><p style="margin-bottom: 0in"><strong>Hot Deployment.</strong> One can | |
now hot deploy web services and handlers.</p> | |
</li> | |
<li><p style="margin-bottom: 0in"><strong>Asynchronous Web | |
Services</strong>. Axis 2.0 now support asynchronous web services | |
invocation and asynchronous web services.</p> | |
</li> | |
<li><p style="margin-bottom: 0in"><strong>MEP Support. </strong>Axis 2.0 | |
now comes handy with support for Message Exchange Patterns.</p> | |
</li> | |
<li><p style="margin-bottom: 0in"><strong>Flexibility</strong>. The Axis | |
architecture gives the developer complete freedom to insert extensions | |
into the engine for custom header processing, system management, or | |
anything else you can imagine.</p> | |
</li> | |
<li><p style="margin-bottom: 0in"><strong>Stability</strong>. Axis defines | |
a set of published interfaces which change relatively slowly compared to | |
the rest of Axis.</p> | |
</li> | |
<li><p style="margin-bottom: 0in"><strong>Component-oriented | |
deployment</strong>. You can easily define reusable networks of Handlers | |
to implement common patterns of processing for your applications, or to | |
distribute to partners.</p> | |
</li> | |
<li><p style="margin-bottom: 0in"><strong>Transport framework</strong>. We | |
have a clean and simple abstraction for designing transports (i.e., | |
senders and listeners for SOAP over various protocols such as SMTP, FTP, | |
message-oriented middleware, etc), and the core of the engine is | |
completely transport-independent.</p> | |
</li> | |
<li><p><strong>WSDL support.</strong> Axis 2.0 supports the <a | |
href="http://www.w3.org/TR/wsdl">Web Service Description Language </a>, | |
version 1.1 and 2.0, which allows you to easily build stubs to access | |
remote services, and also to automatically export machine-readable | |
descriptions of your deployed services from Axis.</p> | |
</li> | |
</ul> | |
<p>We hope you enjoy using Axis. Please note that this is an open-source | |
effort - if you feel the code could use some new features or fixes, please | |
get involved and lend a hand! The Axis developer community welcomes your | |
participation .</p> | |
<p>Let us know what you think!</p> | |
<p>Please send feedback about the package to " <a | |
href="mailto:axis-user@ws.apache.org">axis-user@ws.apache.org </a>" and make | |
sure to prefix the subject of the mail with [Axis2].</p> | |
<h2><a name="_Toc96698078"></a>What's in this release?</h2> | |
<p>This release includes the following features:</p> | |
<ul> | |
<li><p style="margin-bottom: 0in">AXIOM, a SOAP specific streaming XML | |
infoset model for SOAP 1.1/1.2 Messages</p> | |
</li> | |
<li>Complete XML infoset support for AXIOM</li> | |
<li><p style="margin-bottom: 0in">Support for One-Way Messaging and Request | |
Response Messaging</p> | |
</li> | |
<li><p style="margin-bottom: 0in">Modules, mechanism to extend the SOAP | |
Processing Model</p> | |
</li> | |
<li><p style="margin-bottom: 0in">Archives based deployment Model</p> | |
</li> | |
<li><p style="margin-bottom: 0in">WSDL Code Generation Tool for Stub and | |
skeletons</p> | |
</li> | |
<li><p style="margin-bottom: 0in">XML Beans based data binding support</p> | |
</li> | |
<li><p style="margin-bottom: 0in">Support for WS-Addressing, both the | |
submission and final versions</p> | |
</li> | |
<li><p style="margin-bottom: 0in">Client API</p> | |
</li> | |
<li><p style="margin-bottom: 0in">REST Web Service Support</p> | |
</li> | |
<li><p style="margin-bottom: 0in">HTTP transport Support</p> | |
</li> | |
<li><p style="margin-bottom: 0in">SMTP transport Support</p> | |
</li> | |
<li><p style="margin-bottom: 0in">TCP transport Support</p> | |
</li> | |
<li><p style="margin-bottom: 0in">MTOM/SWA attachments support</p> | |
</li> | |
<li><p>SAAJ implementation</p> | |
</li> | |
</ul> | |
<p>The release include following tools</p> | |
<ol> | |
<li><p style="margin-bottom: 0in">Admin Web App</p> | |
</li> | |
<li><p style="margin-bottom: 0in">WSDL2WS, eclipse Plugin/Command line | |
version</p> | |
</li> | |
<li><p style="margin-bottom: 0in">Service Archive Wizard, eclipse Plugin</p> | |
</li> | |
<li><p>Module Archive Wizard, eclipse Plugin</p> | |
</li> | |
</ol> | |
<h2><a name="_Toc96698079"></a>What's still to do?</h2> | |
<p>Please see a list of what we think needs doing - and please consider | |
helping out if you're interested & able!</p> | |
<ul> | |
<li><p style="margin-bottom: 0in">JAX-RPC 1.1 and/or JAX-WS compliance</p> | |
</li> | |
<li><p style="margin-bottom: 0in">Pluggable Data binding support</p> | |
</li> | |
<li><p style="margin-bottom: 0in">SOAP Encoding</p> | |
</li> | |
<li><p style="margin-bottom: 0in">Binary serialization and de-serialization | |
support</p> | |
</li> | |
<li><p style="margin-bottom: 0in">Management Interface for Axis2</p> | |
</li> | |
<li><p style="margin-bottom: 0in">Implementation of other transports. e.g. | |
JMS..</p> | |
</li> | |
<li><p>Web Service Policy Support</p> | |
</li> | |
</ul> | |
<h2><a name="_Toc96697863"></a><!-- Image goes here --> | |
<!--<h3><a name="_Toc96698087"></a>Running the Axis2 standalone server </h3> | |
<p>Since a J2EE servlet container can be heavy in certain cases, a simple socket server is provided with Axis2. </p> | |
Start scripts are inluded in the bin directory of the binary distribution.</p> | |
<p>For windows</p> | |
<p class="command">>start.bat </p> | |
<p>For Linux</p> | |
<p class="command">$start.sh</p> | |
<p>This will start the simple axis server in the default port (8080). To start the server in a non default port | |
the server script can be used. The sever script however needs two parameters, the repository location and the port.</p> | |
<p>For windows</p> | |
<p class="command">>server <i>repository directory</i> <i>port</i> </p> | |
<p>For Linux</p> | |
<p class="command">$server <i>repository directory</i> <i>port</i> </p> | |
<p><b> | |
Note - the directory entered as the repository location needs to have a services directory inside. This is | |
absolutely required and AXIS will not create it automatically in the case of the simple axis server. | |
</b></p> --> | |
Samples</h2> | |
<p>In this section of the user guide we will look at how to write and deploy | |
Web Services and how to write Web Service Clients using Axis2. All the user | |
guide samples are located at the <b><font | |
color="#000000">"samples/userguide/src"</font></b> directory of the binary | |
distribution. So.. let's explore the samples.</p> | |
<p>Note: Please note that the rest of this user guide assumes that the user | |
has downloaded the binary distribution of Axis2. If you have already | |
downloaded the source tree of Axis2 then please create the binary | |
distribution by simply using the maven command <strong>maven dist-bin | |
</strong>This will create the "axis2-0.91-bin.zip" and "axis2-0.91-bin.tar" | |
in the "target/dist" directory. Extract the zip or the tar ball to any | |
directory in your machine and for the explanations purposes we will name this | |
directory as "Axis2Home".</p> | |
<h2><a name="Web_Services_Using_Axis2"></a>Web Services Using Axis2</h2> | |
<p>Before starting, please check whether you have deployed the "axis2.war" in | |
your servlet container and it is working properly. (See <a | |
href="installationguide.html">Installation Guide</a>). User can select any of | |
the following two ways of writing web services using Axis2. </p> | |
<ul> | |
<li><p style="margin-bottom: 0in">Use Axis2's primary interfaces and | |
implement the business logic.</p> | |
</li> | |
<li><p>Start from the WSDL ->Code generate the Skeleton ->Implement | |
the Business Logic.</p> | |
</li> | |
</ul> | |
<h3>Write My Service using Axis2</h3> | |
<h4>MyService</h4> | |
<p>First let's see how we can write a simple Web Service (MyService) using | |
Axis2's primary interfaces and deploy it. For this purpose we will create a | |
Web Service with two operations as follows.</p> | |
<pre>public void ping(OMElement element){} //IN-ONLY operation, just accepts the OMElement and do some processing. | |
public OMElement echo(OMElement element){}//IN-OUT operation, accepts an OMElement and | |
//responds with another OMElement after processing.</pre> | |
<p>Complete code for this example Web Service (MyService) can be found in the | |
"Axis2Home/samples/userguide/src" directory under "userguide/example1" | |
package. As you can see, the two operations are very simple and need no | |
explanations on what they are doing. So let's see how we can write the | |
deployment descriptors for the service and deploy it.</p> | |
<h4>How to write the Web Service?</h4> | |
<p>Write a new Web Service with Axis2 involve four steps</p> | |
<ol> | |
<li><p style="margin-bottom: 0in">Write the Implementation Class</p> | |
</li> | |
<li><p style="margin-bottom: 0in">Write a services.xml file to explain the | |
Web Service</p> | |
</li> | |
<li><p style="margin-bottom: 0in">create a *.aar archive for the Web | |
Service</p> | |
</li> | |
<li><p>Deploy the Web Service</p> | |
</li> | |
</ol> | |
<h4>Step1 :Write the Implementation Class</h4> | |
<p>Provides a implementation class that provide the business logic for the | |
Web Service, it should have methods that match the operations in the Web | |
Service. Unless you have data binding the signature of the methods can have | |
one parameter of type OMElement.</p> | |
<pre>public class MyService{ | |
public void ping(OMElement element){ | |
...... | |
} | |
public OMElement echo(OMElement element){ | |
...... | |
} | |
}</pre> | |
<h4>Step2 :Write the services.xml file</h4> | |
<p>Axis2 uses "services.xml" to keep configurations for a Web Service. Each | |
Web Service deployed in Axis2 needs a "services.xml" containing the | |
configurations. "services.xml" for MyService will be as follows; we will see | |
what each parameter means later.</p> | |
<pre><service name="MyService"> | |
<description> | |
This is a sample Web Service with two operations, echo and ping. | |
</description> | |
<parameter name="ServiceClass" locked="false">userguide.example1.MyService</parameter> | |
<operation name="echo"> | |
<messageReceiver class="org.apache.axis2.receivers.RawXMLINOutMessageReceiver"/> | |
</operation> | |
<operation name="ping"> | |
<messageReceiver class="org.apache.axis2.receivers.RawXMLINOnlyMessageReceiver"/> | |
</operation> | |
</service></pre> | |
<p>As it can be seen, first line of the "services.xml" gives the name of the | |
Web Service. This is used in the URL to the service as the service name. Next | |
comes the description and the service class. The next two xml tags describe | |
the operations that are available in this service with respective message | |
receivers. For the "echo" operation we have used a | |
<strong>RawXMLINOutMessageReceiver</strong> since it is an IN-OUT operation. | |
For IN-ONLY operation, "ping" we have used | |
<strong>RawXMLINOnlyMessageReceiver</strong> as the message receiver.</p> | |
<p>You can write a services.xml file to include a group of services instead | |
of a single service. This makes management and deployment of a set of related | |
services very easy. At runtime you can share information between these | |
services within a single interaction, using the ServiceGroupContext. If you | |
hope to use this functionality the services.xml file should have following | |
format.</p> | |
<pre><serviceGroup> | |
<service name="Service1"> | |
<!-- details for Service1 --> | |
</service> | |
<service name="Service2"> | |
<!-- details for Service2 --> | |
</service> | |
<module ref="ModuleName" /> | |
<parameter name="serviceGroupParam1" locked="false">value 1</parameter> | |
</serviceGroup></pre> | |
<h4>Step3 :Create the Web Service Archive</h4> | |
<p>Axis2 use ".aar" (Axis Archive) file as the deployment package for Web | |
Services. So, for MyService we will use "MyService.aar" with the | |
"services.xml" packaged in the META-INF as shown in the following picture.</p> | |
<p><img src="images/userguide/ServiceItems.jpg" name="Graphic1" | |
align="bottom" width="176" height="91" border="0"></p> | |
<p>To create "MyService.aar" user can first create a jar file containing all | |
the files necessary for the service and then rename the "jar" to "aar" so | |
that Axis2 understands it as a service archive. This has already been created | |
in the "Axis2Home/samples/userguide" directory, and let's use it..</p> | |
<h4>Step4 :Depoly the Web Service</h4> | |
<p>Deploying the service is just a matter of dropping the ".aar" in to | |
"services" directory that can be found in the "\webapps\axis2\WEB-INF" of | |
your servlet container and hence please copy the "MyService.aar" into the | |
"<b>services</b>" directory. Once these steps are completed, please start the | |
servlet container (if you have not already started) and check the link "List | |
Available services" in the page http://localhost:8080/axis2/index.jsp and see | |
whether the MyService is deployed properly. If everything is ok, you will see | |
the following out put..</p> | |
<p align="center"><img src="images/userguide/MyServiceDeployed.jpg" | |
name="Graphic2" align="bottom" width="734" height="766" border="0"></p> | |
<p>If you can see the above output then you have successfully deployed | |
MyService on Axis2. Now let's see how we can write Web Service client to use | |
this services. Axis2 provides an easy way to deploy a Web Services using, | |
index.jsp. (See the installation guide for more information on this)</p> | |
<h3>Axis2SampleDocLitPortType</h3> | |
<p>Now let's see how we can generate the skeleton from a given WSDL and | |
implement the business logic using Axis2. For this we use | |
Axis2SampleDocLit.wsdl that can be found in the <b>wsdl</b> directory under | |
samples.</p> | |
<h4>Generating Skeleton</h4> | |
<p>To generate the skeleton and the required classes you can use the | |
WSDL2Java tool provided in Axis2. This tool is located in the bin directory | |
of the distribution and can be executed using the provided scripts (.bat or | |
.sh). The tool's parameter list is as follows and user can specify these | |
values depending on their requirements.</p> | |
<pre>Usage WSDL2Code -uri :WSDL file location | |
-o : output file location | |
-a : Generate async style code only. Default if off | |
-s : Generate sync style code only. Default if off. takes precedence over -a | |
-p : set custom package name | |
-l : valid languages are java and csharp. Default is java | |
-t : Generate TestCase to test the generated code | |
-ss : Generate server side code (i.e. skeletons).Default is off | |
-sd : Generate service descriptor (i.e. axis2.xml).Default is off.Valid with -ss</pre> | |
<p>We will use the tool with the following parameters and generate the | |
skeleton and the other required classes.</p> | |
<p>Windows users can use the following command in the console </p> | |
<pre style="margin-bottom: 0.2in">WSDL2Java -uri ..\samples\wsdl\Axis2SampleDocLit.wsdl -ss -sd -o ..\samples\src -p org.apache.axis2.userguide</pre> | |
<p>Linux users should switch the file seperator</p> | |
<pre style="margin-bottom: 0.2in">WSDL2Java -uri ../samples/wsdl/Axis2SampleDocLit.wsdl -ss -sd -o ../samples/src -p org.apache.axis2.userguide</pre> | |
<p>This will generate the required classes in the <b>src</b> directory inside | |
samples. This will also generate the schema classes in a directory named | |
<b>schema</b> and please note that these are not source files and should be | |
availed in the class path in order to compile the generated classes</p> | |
<h4>Implement the Business Logic</h4> | |
<p>Locate the skeleton class that can be found under src/userguide directory | |
with the name "Axis2SampleDocLitPortTypeSkeleton.java". This is the skeleton | |
for our web service and we can easily fill the business logic now. The WSDL | |
we have used has three operations as follows.</p> | |
<ul> | |
<!--<li><p style="margin-bottom: 0in">echoVoid - Operation that does not | |
accept any input parameters and also provide no out put parameters. Just | |
perform some task </p> | |
</li>--> | |
<li><p style="margin-bottom: 0in">echoString - Operation that echos a | |
String value </p> | |
</li> | |
<li><p style="margin-bottom: 0in">echoStringArray - Operation that accept | |
string array as the input and echos them back</p> | |
</li> | |
<li><p>echoStruct - Operation that accept a Struct as the input and echos | |
them back.</p> | |
</li> | |
</ul> | |
<!--<h4>echoVoid </h4> | |
<p>Locate the following code segment in the | |
"Axis2SampleDocLitPortTypeSkeleton.java" and fill the business logic. For | |
the explanation purpose we do not need anything to be implemented here.</p> | |
<pre>public void echoVoid(){ | |
//Todo fill this with the necessary business logic | |
}</pre> --> | |
<h4>echoString </h4> | |
<p>Locate the following code segment in the | |
"Axis2SampleDocLitPortTypeSkeleton.java" and fill the business logic as | |
shown below.</p> | |
<pre> public org.soapinterop.xsd.EchoStringArrayReturnDocument | |
echoStringArray(org.soapinterop.xsd.EchoStringArrayParamDocument param2){ | |
//Todo fill this with the necessary business logic | |
return null; | |
}</pre> | |
<p>Once filled with the business logic it will be as follows. The code is | |
simple and the explanations are given in the comments.</p> | |
<pre>public org.soapinterop.xsd.EchoStringReturnDocument | |
echoString(org.soapinterop.xsd.EchoStringParamDocument param6) { | |
//Use the factory to create the output document. | |
EchoStringReturnDocument retDoc = EchoStringReturnDocument.Factory.newInstance(); | |
//send the string back. | |
retDoc.setEchoStringReturn(param6.getEchoStringParam()); | |
return retDoc; | |
}</pre> | |
<p>Similarly following code fragments shows how you can fill the business | |
logic for our first web service.</p> | |
<h4>echoStringArray</h4> | |
<pre>public org.soapinterop.xsd.EchoStringArrayReturnDocument | |
echoStringArray(org.soapinterop.xsd.EchoStringArrayParamDocument param2) { | |
//Use the factory to create the output document. | |
EchoStringArrayReturnDocument retDoc = EchoStringArrayReturnDocument.Factory.newInstance(); | |
//Get the String array from the input parameters. | |
String[] inParams = param2.getEchoStringArrayParam().getStringArray(); | |
ArrayOfstringLiteral retParams = ArrayOfstringLiteral.Factory.newInstance(); | |
//Set the input parameters to the output parameters for echoing. | |
for (int i = 0; i < inParams.length; i++) { | |
retParams.addString(inParams[i]); | |
} | |
//return the output document. | |
retDoc.setEchoStringArrayReturn(retParams); | |
return retDoc; | |
}</pre> | |
<h4>echoStruct</h4> | |
<pre>public org.soapinterop.xsd.EchoStructReturnDocument | |
echoStruct(org.soapinterop.xsd.EchoStructParamDocument param4) { | |
//Use the factory to create the output document. | |
EchoStructReturnDocument retDoc = EchoStructReturnDocument.Factory.newInstance(); | |
//Get the SOAPStrcut from the incoming parameters | |
SOAPStruct inStruct = param4.getEchoStructParam(); | |
//Struct for the sending back | |
SOAPStruct outStruct = SOAPStruct.Factory.newInstance(); | |
//Fill the outgoing struct | |
outStruct.setVarFloat(inStruct.getVarFloat()); | |
outStruct.setVarInt(inStruct.getVarInt()); | |
outStruct.setVarString(inStruct.getVarString()); | |
//Set the outgoing document. | |
retDoc.setEchoStructReturn(outStruct); | |
return retDoc; | |
}</pre> | |
<h4>services.xml</h4> | |
<p> Axis2 uses "services.xml" to hold the configuretions for a particular web | |
service deployed in the Axis2 engine. When we generate the skeleton using the | |
WSDL2Java tool, it will also generate the required services.xml for this web | |
service as well and it can be found in the same directory as the skeleton. | |
The generated services.xml is as follows.</p> | |
<pre><!--Auto generated Axis Service XML--> | |
<service name="Axis2SampleDocLitPortTypeSkeletonTest"> | |
<parameter locked="xsd:false" name="ServiceClass">userguide.Axis2SampleDocLitPortTypeSkeleton</parameter> | |
<!--Mounting the method echoStringArray--> | |
<operation name="echoStringArray"> | |
<messageReceiver class="userguide.Axis2SampleDocLitPortTypeMessageReceiver"/> | |
</operation> | |
<!--Mounting the method echoStruct--> | |
<operation name="echoStruct"> | |
<messageReceiver class="userguide.Axis2SampleDocLitPortTypeMessageReceiver"/> | |
</operation> | |
<!--Mounting the method echoString--> | |
<operation name="echoString"> | |
<messageReceiver class="userguide.Axis2SampleDocLitPortTypeMessageReceiver"/> | |
</operation> | |
</service></pre> | |
<p>As it can be seen, first line of the "services.xml" gives the name of the | |
Web Service. This is used in the URL to the service as the service name. Next | |
comes the description and the service class. The next xml tags describe the | |
operations that are available in this service with respective message | |
receivers.</p> | |
<h4>Packaging</h4> | |
<p>Next step in the process is to package the classes in a .aar (axis2 | |
archive) and deploy it in Axis2. When the WSDL2Java tool generate the | |
skeleton it will also generate the required data binding classes as well. | |
These schema related classes are located in the <b>schema </b>directory of | |
the generated code. Copy this to your class path and compile the skeleton and | |
the supporting classes. In order to create the .aar file, let's create the | |
following directory structure with the required files and then simply use jar | |
command to package it.</p> | |
<p><img src="images/userguide/DirectoryStructure.JPG" name="Graphic3" | |
align="bottom" width="164" height="142" border="0"></p> | |
<p>Go to the top level directory where you can find the class files for the | |
above service (i.e. one level up in the directory structure shown above) and | |
type the following command in a command line.</p> | |
<pre style="margin-bottom: 0.2in">jar -cf Axis2SampleDocLitPortType.aar .</pre> | |
<p>Deploying the service is just a matter of dropping the ".aar" in to | |
"services" directory that can be found in the "\webapps\axis2\WEB-INF" of | |
your servlet container and hence please copy the "echo.aar" into the | |
"<b>services</b>" directory. Once these steps are completed, please start the | |
servlet container (if you have not already started) and check the link "List | |
Available services" in the page http://localhost:8080/axis2/index.jsp and see | |
whether the Axis2SampleDocLitPortType is deployed properly. If everything is | |
ok, you will see the following out put..</p> | |
<p align="center"><img src="images/userguide/ServiceDeployed.JPG" | |
name="Graphic4" align="bottom" width="734" height="764" border="0"></p> | |
<p>If you can see the above output then you have successfully deployed | |
Axis2SampleDocLitPortType on Axis2. Now let's see how we can write Web | |
Service client to use this services. Axis2 provides an easy way to deploy a | |
Web Services using, index.jsp. (See the installation guide for more | |
information on this)</p> | |
<h2><a name="Web_Service_Clients_Using_Axis2"></a>Web Service Clients Using Axis2</h2> | |
<p>Web services can be used to provide wide range of functionality to the | |
users ranging from simple less time consuming operations such as | |
"getStockQuote" to time consuming business services. When we utilize (invoke | |
using client applications) these Web Service we cannot use some simple | |
generic invocation paradigm that suites all the timing complexities involved | |
in the service operations. For example, if we use a single transport channel | |
(such as HTTP) to invoke a Web Service with and IN-OUT operation, that take | |
long time to complete, then in most of the time we may end up with | |
"connection time outs". On the other hand, if there are simultaneous service | |
invocations that we need to perform from a single client application, then | |
the use of a "blocking" client API will degrade the performance of the client | |
application. Similarly there are various other consequences such as One-Way | |
transports that come in to play when we need 's try<< to analyze some | |
common service invocation paradigms.</p> | |
<p>Many web service engines provide the users with a Blocking and | |
Non-Blocking client APIs.</p> | |
<ul> | |
<li><p style="margin-bottom: 0in"><b>Blocking API</b> -Once the service | |
invocation is called, the client application hangs and gets the control | |
back only when the operation completes and the client receives a response | |
or a fault. This is the simplest way of invoking Web Services and suites | |
many business situations.</p> | |
</li> | |
<li><p><b>Non-Blocking API </b>- A callback or polling based API and hence | |
once a service invocation is called, the client application immediately | |
gets the control back and the response is retrieved using the callback | |
object provided. This approach provides the flexibility to the client | |
application to invoke several Web Services simultaneously with out | |
blocking on the operation already invoked.</p> | |
</li> | |
</ul> | |
<p>Both these mechanism works in the API level and let's name the | |
asynchronous behavior that we can get using the Non-Blocking API as <b>API | |
Level Asynchrony.</b></p> | |
<p>Both these mechanisms use single transport connection to send the request | |
and to receive the response. They severely lags the capability of using two | |
transport connections for the request and the response (either One-Way of | |
Two-Way). So both of these mechanisms fail to address the problem of long | |
running transactions (the transport connection may times-out before the | |
operation completes). A possible solution would be to use two separate | |
transport connections for request and response. The asynchronous behavior | |
that we gain using can be called, <b>Transport Level Asynchrony</b>.</p> | |
<p>By combining the two we can obtain four different invocation patterns for | |
web services as shown in the following table.</p> | |
<a name="table1"></a> | |
<table width="100%" border="1" cellpadding="0" cellspacing="0"> | |
<tbody> | |
<tr> | |
<td width="33%" height="19"><p>API (Blocking/Non-Blocking)</p> | |
</td> | |
<td width="33%"><p> Dual Transports (Yes/No)</p> | |
</td> | |
<td width="33%"><p>Description</p> | |
</td> | |
</tr> | |
<tr> | |
<td width="33%" height="19"><p>Blocking</p> | |
</td> | |
<td width="33%"><p>No</p> | |
</td> | |
<td width="33%"><p>Simplest and the familiar invocation pattern</p> | |
</td> | |
</tr> | |
<tr> | |
<td width="33%" height="19"><p>Non-Blocking</p> | |
</td> | |
<td width="33%"><p>No</p> | |
</td> | |
<td width="33%"><p>Using callbacks or polling</p> | |
</td> | |
</tr> | |
<tr> | |
<td width="33%" height="19"><p>Blocking</p> | |
</td> | |
<td width="33%"><p>Yes</p> | |
</td> | |
<td width="33%"><p>This is useful when the service operation is IN-OUT | |
in nature but the transport used is One-Way (e.g. SMTP)</p> | |
</td> | |
</tr> | |
<tr> | |
<td width="33%" height="19"><p>Non-Blocking</p> | |
</td> | |
<td width="33%"><p>Yes</p> | |
</td> | |
<td width="33%"><p>This is can be used to gain the maximum asynchronous | |
behavior. No blocking in the API level and also in the transport | |
level</p> | |
</td> | |
</tr> | |
</tbody> | |
</table> | |
<p>Axis2 provides the user with all these possibilities to invoke Web | |
Services. In addition Axis2 provides a data binding support making the life | |
easy for developers writing Web Service client applications. In this user | |
guide we will first see how we can write Web Service clients using the | |
Axis2's primary APIs and later we will see how we can use generated stubs to | |
simply write Web Service Clients.</p> | |
<h3>Using Axis2's Primary APIs</h3> | |
<h3>EchoBlockingClient</h3> | |
<p>Axis2 provides the user with several invocation patterns for Web Services, | |
ranging from pure blocking single channel invocations to a non-blocking dual | |
channel invocations. First let's see how we can write a client to invoke | |
"echo" operation of "MyService" using the simplest good old blocking | |
invocation. The client code that you need to write will be as follows.</p> | |
<pre> try { | |
OMElement payload = ClientUtil.getEchoOMElement(); | |
<font color="#33cc00"> Options options = new Options(); | |
options.setTo(targetEPR); | |
options.setListenerTransportProtocol(Constants.TRANSPORT_HTTP); | |
options.setUseSeparateListener(false); | |
Call call = new Call(); | |
call.setClientOptions(options);</font> | |
<font color="#33cc00"> OMElement result = (OMElement) call.invokeBlocking("echo", payload);</font> | |
StringWriter writer = new StringWriter(); | |
result.serializeWithCache(new OMOutput(XMLOutputFactory.newInstance().createXMLStreamWriter(writer))); | |
writer.flush(); | |
System.out.println(writer.toString()); | |
} catch (AxisFault axisFault) { | |
axisFault.printStackTrace(); | |
} catch (XMLStreamException e) { | |
e.printStackTrace(); | |
} | |
}</pre> | |
<p>The green lines shows the set of operations that you need to perform | |
in-order to invoke a web service while the rest is used to create the | |
OMElement that needs to be sent and to display the response OMElement. To | |
test this client you can use the provided ant build file that can be found in | |
the "Axis2Home/samples" directory. Run the "testEchoBlockingClient" target . | |
if you can see the response OMElement printed in your command line then you | |
have successfully tested the client as well. </p> | |
<h3>PingClient</h3> | |
<p>In the Web Service "MyService" we had a IN-ONLY operation with the name | |
"ping" (see Web Services Using Axis2). So let's write a client to invoke this | |
operation as well. The client code will be as follows.</p> | |
<pre> try { | |
OMElement payload = ClientUtil.getPingOMElement(); | |
MessageSender msgSender = new MessageSender(); | |
Options options = new Options();<br> msgSender.setClientOptions(options);<br> options.setTo(targetEPR); | |
msgSender.send("ping", payload); | |
} catch (AxisFault axisFault) { | |
axisFault.printStackTrace(); | |
}</pre> | |
<p>Since we are accessing a IN-ONLY operation we can directly use the | |
"MessageSender" to invoke this operation. As it can be seen in the above code | |
, it is very straight forward to invoke this type of operation. MessageSender | |
will not block the invocation, hence it will return the control immediately | |
back to the client. You can test this client by running the target | |
"testPingClient" of the ant build file at "Axis2Home/samples".</p> | |
<p>Ok, we have invoked the two operations in our service, Are we done? No!, | |
there are lot more to explore, Let's see some other ways to invoke the same | |
operations.</p> | |
<h3>EchoNonBlockingClient</h3> | |
<p>In the EchoBlockingClient once the "call.invokeBlocking("echo", payload);" | |
is called, the client is blocked till the operation is completed. This | |
behavior is not desirable when there are many Web Service invocations to be | |
done in a single client application. A solution, would be to use a | |
Non-Blocking API to invoke web services. Axis2 provides a callback based | |
non-blocking API for users.</p> | |
<p>A sample client for this can be found under | |
"Axis2Home/samples/userguide/src/userguide/clients" with the name | |
EchoNonBlockingClient. If we consider the changes that the user may have to | |
do with respect to the "EchoBlockingClient" that we have already seen, it | |
will be as follows.</p> | |
<pre style="margin-bottom: 0.2in">call.invokeNonBlocking("echo", payload, callback);</pre> | |
<p>The invocation accepts a callback object as a parameter. Axis2 client API | |
provides an abstract Callback with the following methods.</p> | |
<pre>public abstract void onComplete(AsyncResult result); | |
public abstract void reportError(Exception e); | |
public boolean isComplete() {}</pre> | |
<p>The user is expected to implement the "onComplete " and "reportError " | |
methods of their extended call back class. Axis2 engine calls the onComplete | |
method once the Web Service response is received by the Axis2 Client API | |
(Call). This will eliminate the blocking nature of the Web Service | |
invocations and provides the user with the flexibility to use Non Blocking | |
API for Web Service Clients.</p> | |
<p>To run the sample client ( EchoNonBlockingClient) you can simply use the | |
"testEchoNonBlockingClient" target of the ant file found at the | |
"Axis2Home/samples" directory.</p> | |
<h3>EchoNonBlockingDualClient</h3> | |
<p>The solution provided by the Non-Blocking API has one limitation when it | |
comes to Web Service invocations which takes long time to complete. The | |
limitation is due to the use of single transport connection to invoke the Web | |
Service and to retrieve the response. In other words, client API provides a | |
non blocking invocation mechanism for the users, but the request and the | |
response comes in a single transport connection (needs two way transports | |
like HTTP). Long running Web Service invocations or Web Service invocations | |
using One-Way transports (like SMTP) cannot be utilized by simply using a non | |
blocking invocation. </p> | |
<p>The trivial solution is to use separate transport connections (either | |
One-Way or Two-Way) for the request and response. The next problem that needs | |
to be solved is the correlation (correlating the request and the response). | |
<a href="http://www.w3.org/Submission/ws-addressing/">WS-Addressing</a> | |
provides a neat solution to above using <wsa:MessageID> and | |
<wsa:RelatesTo> headers. Axis2 provides support for addressing based | |
correlation mechanism and a complying Client API to invoke Web Services with | |
two transport connections. (core of Axis2 does not depend on WS-Addressing, | |
and it is the addressing like properties, hence Axis2 has the flexibility to | |
use different versions of addressing)</p> | |
<p>Users can select between Blocking or Non-Blocking APIs for the Web Service | |
clients with two transport connections. By simply using a boolean flag, the | |
same API can be used to invoke web services (IN-OUT operations) using two | |
separate transport connections. Let's see how we can do it using an example. | |
Following code fragment shows how to invoke the same "echo" operation, using | |
Non-Blocking API with two transport connections<strong>. The ultimate | |
asynchrony!!</strong></p> | |
<pre> try { | |
OMElement payload = ClientUtil.getEchoOMElement(); | |
Options options = new Options();<br> options.setTo(targetEPR);<br> options.setListenerTransportProtocol(Constants.TRANSPORT_HTTP); | |
//The boolean flag informs the axis2 engine to use two separate transport connection | |
//to retrieve the response.<br> options.setUseSeparateListener(true); | |
Call call = new Call();<br> call.setClientOptions(options); | |
</pre> | |
<pre> | |
//Callback to handle the response | |
Callback callback = new Callback() { | |
public void onComplete(AsyncResult result) { | |
try { | |
StringWriter writer = new StringWriter(); | |
result.serializeWithCache(new OMOutput(XMLOutputFactory.newInstance() | |
.createXMLStreamWriter(writer))); | |
writer.flush(); | |
System.out.println(writer.toString()); | |
} catch (XMLStreamException e) { | |
reportError(e); | |
} | |
} | |
public void reportError(Exception e) { | |
e.printStackTrace(); | |
} | |
}; | |
//Non-Blocking Invocation | |
call.invokeNonBlocking("echo", payload, callback); | |
//Wait till the callback receives the response. | |
while (!callback.isComplete()) { | |
Thread.sleep(1000); | |
} | |
<font color="#33cc00">call.close();</font> | |
} catch (AxisFault axisFault) { | |
axisFault.printStackTrace(); | |
} catch (Exception ex) { | |
ex.printStackTrace(); | |
}</pre> | |
<p><font | |
color="#0000ff"><font color="#000000">The boolean flag (value true) in | |
the "<b>call.setUseSeparateListener(...)</b>" method informs the Axis2 engine to use | |
separate transport connections for request and response. Finally | |
"<b>call.close()</b>" informs the Axis2 engine to stop the client side | |
listener started to retrieve the response.</font></font></p> | |
<p>Before we run the sample client we need one more step to perform. As | |
mentioned earlier Axis2 uses addressing based correlation mechanism and hence | |
we need to "engage" addressing module in the server side as well. According | |
to the Axis2 architecture addressing module is deployed in the | |
"<strong>pre-dispatch</strong>" phase (See <a | |
href="file:///G:/Documents and Settings/Jaliya/Desktop/Axis2ArchitectureGuide.html">Architecture | |
Guide</a> for more details about phases) and hence "engaging" means simply | |
adding module reference in the "axis2.xml" (NOT the "services.xml"). Please | |
add the following line to the "axis2.xml" that you can find in the | |
"/webapps/axis2/WEB-INF" directory in the servlet container. </p> | |
<pre style="margin-bottom: 0.2in"> <module ref="addressing"/></pre> | |
<p>Note: Please note that<font color="#000000"> once you change the | |
"axis2.xml" you need to restart the servlet container.</font></p> | |
<p>This will enable the addressing in the server side and now you can test | |
the "TestEchoNonBlockingDualClient" using the "testEchoNonBlockingDualClient" | |
target of the ant file found at "Axis2Home/samples" directory. If you can see | |
the response OMElement printed in the client side, that means you have | |
successfully tested the Non Blocking API with two transport channels at the | |
client side.</p> | |
<h3>EchoBlockingDualClient</h3> | |
<p>This is again a two transport request/response client, but this time, we | |
use a Blocking API in the client code. Sample code for this can be found in | |
the "Axis2Home/samples/userguide/src/userguide/clients/" directory and the | |
explanation is similar to the EchoNonBlockingDualClient, except that here we | |
do not use a callback object to handle response. This is a very useful | |
mechanism when the service invocation is IN-OUT in nature and the transports | |
are One-Way (e.g. SMTP). For the sample client we use two HTTP connections | |
for request and response. User can test this client using the | |
"echoBlockingDualClient" target of the ant build file found in the | |
"Axis2Home/samples" directory.</p> | |
<p>See <a href="#configTransport">Configuring Transports</a> for use | |
different transports.</p> | |
<h3>With Data Binding</h3> | |
<p>Axis2 provides the data binding support for Web Service client as well. | |
The user can generate the required stubs from a given WSDL with the other | |
supporting classes. Let's see how we can generate the stubs for the WSDL we | |
have used earlier to generate the skeleton for the | |
"Axis2SampleDocLitPortType". Simply run the WSDL2Java tool that can be found | |
in the bin directory of the Axis2 distribution using the following | |
command.</p> | |
<pre style="margin-bottom: 0.2in">WSDL2Java -uri ..\samples\wsdl\Axis2SampleDocLit.wsdl -o ..\samples\src -p org.apache.axis2.userguide</pre> | |
<p>This will generate the required stub "Axis2SampleDocLitPortTypeStub.java" | |
that can be used to invoke the Web Service Axis2SampleDocLitPortType. Let's | |
see how we can use this stub to write Web Service clients to utilize the Web | |
Service Axis2SampleDocLitPortType (the service that we have already | |
deployed).</p> | |
<h3>Client for echoVoid Operation</h3> | |
<p>Following code fragment shows the necessary code for utilizing the | |
echoVoid operation of the Axis2SampleDocLitPortType that we have already | |
deployed. In this operation, a blank SOAP body element is sent to the Web | |
Service and the same SOAP envelope is echoed back.</p> | |
<pre> try { | |
//Create the stub by passing the AXIS_HOME and target EPR. | |
//We pass null to the AXIS_HOME and hence the stub will use the current directory sa the AXIS_HOME | |
Axis2SampleDocLitPortTypeStub stub = new Axis2SampleDocLitPortTypeStub(null, | |
"http://localhost:8080/axis2/services/Axis2SampleDocLitPortType"); | |
stub.echoVoid(); | |
} catch (Exception e) { | |
e.printStackTrace(); | |
}</pre> | |
<h3>Client for echoString Operation</h3> | |
<p>Following code fragment shows the necessary code for utilizing the | |
echoString operation of the Axis2SampleDocLitPortType that we have already | |
deployed. The code is very simple to understand and the explanations are | |
given in the comments.</p> | |
<pre>try { | |
//Create the stub by passing the AXIS_HOME and target EPR. | |
//We pass null to the AXIS_HOME and hence the stub will use the current directory sa the AXIS_HOME | |
Axis2SampleDocLitPortTypeStub stub= new Axis2SampleDocLitPortTypeStub(null, | |
"http://localhost:8080/axis2/services/Axis2SampleDocLitPortType"); | |
//Create the request document to be sent. | |
EchoStringParamDocument reqDoc= EchoStringParamDocument.Factory.newInstance(); | |
reqDoc.setEchoStringParam("Axis2 Echo"); | |
//invokes the web service. | |
EchoStringReturnDocument resDoc=stub.echoString(reqDoc); | |
System.out.println(resDoc.getEchoStringReturn()); | |
} catch (Exception e) { | |
e.printStackTrace(); | |
}</pre> | |
<p>Similarly following code fragments shows client side code for | |
echoStringArray operation and echoStruct operation respectively.</p> | |
<h3>Client for echoStringArray Operation</h3> | |
<pre>try { | |
//Create the stub by passing the AXIS_HOME and target EPR. | |
//We pass null to the AXIS_HOME and hence the stub will use the current directory sa the AXIS_HOME | |
Axis2SampleDocLitPortTypeStub stub = new Axis2SampleDocLitPortTypeStub(null, | |
"http://localhost:8080/axis2/services/Axis2SampleDocLitPortType"); | |
//Create the request document to be sent. | |
EchoStringArrayParamDocument reqDoc = EchoStringArrayParamDocument.Factory.newInstance(); | |
ArrayOfstringLiteral paramArray = ArrayOfstringLiteral.Factory.newInstance(); | |
paramArray.addString("Axis2"); | |
paramArray.addString("Echo"); | |
reqDoc.setEchoStringArrayParam(paramArray); | |
EchoStringArrayReturnDocument resDoc = stub.echoStringArray(reqDoc); | |
//Get the response params | |
String[] resParams = resDoc.getEchoStringArrayReturn().getStringArray(); | |
for (int i = 0; i < resParams.length; i++) { | |
System.out.println(resParams[i]); | |
} | |
} catch (Exception e) { | |
e.printStackTrace(); | |
}</pre> | |
<h3>Client for echoStruct Operation</h3> | |
<pre>try { | |
//Create the stub by passing the AXIS_HOME and target EPR. | |
//We pass null to the AXIS_HOME and hence the stub will use the current directory sa the AXIS_HOME | |
Axis2SampleDocLitPortTypeStub stub = new Axis2SampleDocLitPortTypeStub(null, | |
"http://localhost:8080/axis2/services/Axis2SampleDocLitPortType"); | |
//Create the request Document | |
EchoStructParamDocument reqDoc = EchoStructParamDocument.Factory.newInstance(); | |
//Create the complex type | |
SOAPStruct reqStruct = SOAPStruct.Factory.newInstance(); | |
reqStruct.setVarFloat(100.50F); | |
reqStruct.setVarInt(10); | |
reqStruct.setVarString("High"); | |
reqDoc.setEchoStructParam(reqStruct); | |
//Service invocation | |
EchoStructReturnDocument resDoc = stub.echoStruct(reqDoc); | |
SOAPStruct resStruct = resDoc.getEchoStructReturn(); | |
System.out.println("floot Value :" + resStruct.getVarFloat()); | |
System.out.println("int Value :" + resStruct.getVarInt()); | |
System.out.println("String Value :" + resStruct.getVarString()); | |
} catch (Exception e) { | |
e.printStackTrace(); | |
}</pre> | |
<h2><a name="Modules"></a>Modules</h2> | |
<p>Axis2 provides an extended support for modules (See <a | |
href="file:///G:/Documents and Settings/Jaliya/Desktop/Axis2ArchitectureGuide.html">Architecture | |
Guide</a> for more details about modules in axis2). Let's see how we can | |
create a custom module and deploy it to the MyService that we have created | |
earlier. Following steps shows the actions that needs to be performed to | |
deploy a custom module for a given Web Service.</p> | |
<ol> | |
<li><p style="margin-bottom: 0in">Create the Module Implementation</p> | |
</li> | |
<li><p style="margin-bottom: 0in">Create the Handlers</p> | |
</li> | |
<li><p style="margin-bottom: 0in">Create the module.xml</p> | |
</li> | |
<li><p style="margin-bottom: 0in">Modify the "axis2.xml" (if you need | |
custom phases)</p> | |
</li> | |
<li><p style="margin-bottom: 0in">Modify the "services.xml" to engage | |
modules at the deployment time.</p> | |
</li> | |
<li><p style="margin-bottom: 0in">Package in a ".mar" (Module Archive)</p> | |
</li> | |
<li><p>Deploy the module in Axis2</p> | |
</li> | |
</ol> | |
<h3>MyService with a Logging Module</h3> | |
<p>Let's write a simple logging module for our sample. This module contains | |
one handler that just logs the message that is passed though it. Axis2 uses | |
."mar" (Module Archive) to deploy modules in Axis2. Following diagram shows | |
the file structure inside that needs to be there in the ".mar" archive. Let's | |
create all these and see how it works.</p> | |
<p><img src="images/userguide/ModuleView.jpg" name="Graphic5" align="bottom" | |
width="185" height="120" border="0"></p> | |
<h4>Step1 : LoggingModule Class</h4> | |
<p>LoggingModule is the implementation class of the Axis2 module. Axis2 | |
modules should implement the "org.apache.axis2.modules.Module" interface with | |
the following methods.</p> | |
<pre>public void init(AxisConfiguration axisSystem) throws AxisFault;//Initialize the module | |
public void shutdown(AxisConfiguration axisSystem) throws AxisFault;//End of module processing</pre> | |
<p>These methods can be used to control the module initialization and the | |
termination. With the input parameter AxisConfiguration, the user is provided | |
with the complete configuration hierarchy and this can be used to fine tune | |
the module behavior by the module writers. For the simple logging service, we | |
can keep these methods blank in our implementation class.</p> | |
<h4>Step2 : LogHandler</h4> | |
<p>A module in axis2 can contain, one or more handlers that perform various | |
SOAP header processing at different phases. (See<a | |
href="file:///G:/Documents and Settings/Jaliya/Desktop/Axis2ArchitectureGuide.html"> | |
Architecture Guide</a> for more information about phases). For the logging | |
module we will write a handle with the following methods. "public void | |
invoke(MessageContext ctx);" is the method that is called by the Axis2 engine | |
when the control is passed to the handler. "public void revoke(MessageContext | |
ctx);" is called when the handlers are revoked by the Axis2 engine.</p> | |
<pre>public class LogHandler extends AbstractHandler implements Handler { | |
private Log log = LogFactory.getLog(getClass()); | |
private QName name; | |
public QName getName() { | |
return name; | |
} | |
public void invoke(MessageContext msgContext) throws AxisFault { | |
log.info(msgContext.getEnvelope().toString()); | |
} | |
public void revoke(MessageContext msgContext) { | |
log.info(msgContext.getEnvelope().toString()); | |
} | |
public void setName(QName name) { | |
this.name = name; | |
} | |
}</pre> | |
<h4>Step3 : module.xml</h4> | |
<p>"module.xml" contains the deployment configurations for a particular | |
module. It contains details such as Implementation class of the module (in | |
this example it is the "LoggingModule" class and the various handlers that | |
will run in different phases. "module.xml" for the logging module will be as | |
follows.</p> | |
<pre><module name="logging" class="userguide.loggingmodule.LoggingModule "> | |
<inflow> | |
<handler name="InFlowLogHandler" class="userguide.loggingmodule.LogHandler"> | |
<order phase="loggingPhase" /> | |
</handler> | |
</inflow> | |
<outflow> | |
<handler name="OutFlowLogHandler" class="userguide.loggingmodule.LogHandler"> | |
<order phase="loggingPhase"/> | |
</handler> | |
</outflow> | |
<Outfaultflow> | |
<handler name="FaultOutFlowLogHandler" class="userguide.loggingmodule.LogHandler"> | |
<order phase="loggingPhase"/> | |
</handler> | |
</Outfaultflow> | |
<INfaultflow> | |
<handler name="FaultInFlowLogHandler" class="userguide.loggingmodule.LogHandler"> | |
<order phase="loggingPhase"/> | |
</handler> | |
</INfaultflow> | |
</module></pre> | |
<p>As it can be seen there are four phases defined in this "module.xml"</p> | |
<ol> | |
<li><p style="margin-bottom: 0in">inflow - Represents the | |
handler chain that will run when a message is coming in. </p> | |
</li> | |
<li><p style="margin-bottom: 0in">outflow - Represents the | |
handler chain that will run when the message is going out. </p> | |
</li> | |
<li><p style="margin-bottom: 0in">Outfaultflow - Represents the | |
handler chain that will run when there is a fault and the fault is going | |
out </p> | |
</li> | |
<li><p>INfaultflow - Represents the handler chain that will run when | |
there is a fault and the fault is coming in </p> | |
</li> | |
</ol> | |
<p>Following set of tags describe the name of the handler, handler class and | |
the phase in which this handler going to run."InFlowLogHandler" is the name | |
given for the particular instance of this handler. The property, class is the | |
actual implementation class for this handler. Since we are writing logging | |
handler, we can reuse the same handler in all these phases, however this may | |
not be the same for all the modules. "<order phase="loggingPhase" />" | |
describes the phase in which this handler runs.</p> | |
<pre><handler name="InFlowLogHandler" class="userguide.loggingmodule.LogHandler"> | |
<order phase="loggingPhase" /> | |
</handler></pre> | |
<h4>Step 4: Modify the "axis2.xml"</h4> | |
<p>In this handler the phase "loggingPhase" is defined by the module writer. | |
It is not a pre-defined handler phase and hence the module writer should | |
introduce it to the "axis2.xml" (NOT the services.xml) so that Axis2 engine | |
knows where to place the handler in different "flows" (<br> | |
InFlow, OutFlow, etc...). Following xml lines shows the respective changes to | |
the "axis2.xml" in order for us to deploy this logging module in Axis2 | |
engine. This is an extract of the phase section of the "axis2.xml".</p> | |
<pre><!-- ================================================= --> | |
<!-- Phases --> | |
<!-- ================================================= --> | |
<phaseOrder type="inflow"> | |
<!-- System pre defined phases --> | |
<phase name="TransportIn"/> | |
<phase name="PreDispatch"/> | |
<phase name="Dispatch"/> | |
<phase name="PostDispatch"/> | |
<!-- System pre defined phases --> | |
<!-- After Postdispatch phase module author or or service author can add any phase he want --> | |
<phase name="<font color="#33cc00">loggingPhase</font>"/> | |
</phaseOrder> | |
<phaseOrder type="outflow"> | |
<!-- user can add his own phases to this area --> | |
<phase name="<font color="#33cc00">loggingPhase</font>"/> | |
</phaseOrder> | |
<phaseOrder type="INfaultflow"> | |
<!-- user can add his own phases to this area --> | |
<phase name="<font color="#33cc00">loggingPhase</font>"/> | |
</phaseOrder> | |
<phaseOrder type="Outfaultflow"> | |
<!-- user can add his own phases to this area --> | |
<phase name="<font color="#33cc00">loggingPhase</font>"/> | |
</phaseOrder></pre> | |
<p>Shown in green, the custom phase "loggingPhase" is placed in all the | |
flows, and hence that phase will be called in all the message flows in the | |
engine. Since our module is associated with this phase, the LogHandler is now | |
have a phase for it to get executed.</p> | |
<h4>Step5 : Modify the "services.xml"</h4> | |
<p>Up to this point we have created the required classes and the | |
configuration descriptions for the logging module and by changing the | |
"axis2.xml" we have created the required phases for the logging module. Now | |
the next step is to "<b>engage</b>" (use) this module in one of our services. | |
For this, let's use the same Web Service that we have used throughout the | |
user guide, the MyService. However, since we need to modify the | |
"services.xml" of the MyService in order for us engage this module, we use a | |
separate Web Service, but with the similar operations. The code for this | |
service can be found in the | |
"Axis2Home/samples/userguide/src/userguide/example2" directory. The simple | |
changes that we have done to he "services.xml' are shown in the green color | |
in the following lines of xml.</p> | |
<pre><service name="<font color="#33cc00">MyServiceWithModule</font>"> | |
<description> | |
This is a sample Web Service with a logging module engaged. | |
</description> | |
<font color="#33cc00"><module ref="logging"/></font> | |
<parameter name="ServiceClass" locked="xsd:false">userguide.example2.MyService</parameter> | |
<operation name="echo"> | |
<messageReceiver class="org.apache.axis2.receivers.RawXMLINOutMessageReceiver"/> | |
</operation> | |
<operation name="ping"> | |
<messageReceiver class="org.apache.axis2.receivers.RawXMLINOutMessageReceiver"/> | |
</operation> | |
</service></pre> | |
<p>In this example we have changed the service name (the implementation class | |
is very similar to what we have used earlier although it is in a different | |
package). In addition we have added the line <b>"<module | |
ref="logging"/>"</b> to the "services.xml". This informs the Axis2 engine | |
that the module "logging" should be engaged for this service. The handler in | |
side the module will be executed in their respective phases as described by | |
the "module.xml".</p> | |
<p><b>Step6 : Packaging</b></p> | |
<p>Before deploying the module we need to create the ".mar" file for this | |
module. This can be done, using the "jar" command and then renaming the | |
created jar file, or you can find the "Logging.mar" that is already created | |
for you in the "Axis2Home/samples/userguide" directory.</p> | |
<h4>Step7 : Deploy the Module in Axis2</h4> | |
<p>Deploying a module in Axis2 require the user to create a directory with | |
the name "modules" in the "webapps/axis2/WEB-INF" directory of their servlet | |
container and then copying the ".mar" file to that directory. So let's first | |
create the "modules" directory and drop the "LoggingModule.mar" in to this | |
directory.</p> | |
<p>Although the required changes to the "services.xml" is very little, we | |
have created a separate service archive (MyServiceWithModule.aar) for users | |
to just deploy and see. Please deploy this service using the same steps that | |
you use to deploy "MyService" and copy the "LoggingModule.mar" file to the | |
"modules" directory. Then by using the "TestWebServiceWithModuleClient.bat" | |
and "TestWebServiceWithModuleClient.sh" in the | |
"Axis2Home/samples/userguide/src/userguide/clients/bin" directory.</p> | |
<p>Note: To see the logs, the user needs to modify the "log4j.properties" to | |
log INFO as well. The property file is located in | |
"webapps\axis2\WEB-INF\classes" of your servlet container. Change the line | |
"log4j.rootCategory= ERROR, LOGFILE" to "log4j.rootCategory=INFO, ERROR, | |
LOGFILE".</p> | |
<h2> </h2> | |
<h2><a name="Other_Samples"></a>Other Samples</h2> | |
<p>To show the power and usage of Axis2, three standard samples are shipped | |
with the binary distribution. These are meant to interact with outside web | |
services and prove the capabilities of the Axis2 system.</p> | |
<p>The included samples are</p> | |
<ul> | |
<li><p style="margin-bottom: 0in">Google spell checker sample<!--<li>Google search sample</li> --> | |
</p> | |
</li> | |
<li><p>Amazon queuing sample</p> | |
</li> | |
</ul> | |
<p>Following is a simple introduction to each of the samples. Each sample | |
contains it's own help document that says about the usage and the advanced | |
operations of that particular sample.</p> | |
<h4>Google spell checker sample</h4> | |
<p>This includes a spell checker program that uses the Google spell checking | |
service. It demonstrates the blocking and non-blocking modes of calling the | |
service. This sample can be found at the samples\googleSpellcheck folder and | |
can be easily started using either the batch file or the shell script.</p> | |
<h4>Google search sample</h4> | |
<p>This includes a search program that uses the familiar Google search over | |
the SOAP API. It utilizes the non-blocking mode of the client API. This | |
sample can be found at the samples\googleSearch folder and can be easily | |
started using either the batch file or the shell script.</p> | |
<h4>Amazon queuing service</h4> | |
<p>Amazon queuing service sample shows how to use the Amazon queuing service. | |
it has two user interfaces , one to enqueue and the other dequeue. This | |
sample is included in the samples\amazonQS and also contains the batch/shell | |
scripts to run.</p> | |
<h3>Where are these samples ?</h3> | |
<p>The most obvious place to look for the samples are the binary | |
distribution. all these samples are included in the samples directory in the | |
binary distribution. The shell scripts and the batch files are in fact | |
written to use the binary distributions root directory as the home to find | |
the libraries.</p> | |
<p>The other way is to build the samples from source. Moving to the | |
modules/samples and running maven will create the samples in the | |
target/samples directory. However if the samples need to be started using the | |
shell scripts (or the batch files) then the AXIS_HOME environment need to be | |
set.( the "guessed" AXIS_HOME would not be correct in this case)</p> | |
<h2><a name="Tools"></a>Tools</h2> | |
<p>Axis2 is shipped with two standard tools. Both the tools are Eclipse | |
plug-ins, the Codegen tool even has the accompanying Ant task and the command | |
line tool.</p> | |
<p>Documentation for the code generator tool is available for the <a | |
href="CodegenToolReference.html">Codegen wizard</a> and the <a | |
href="ServiceArchiveToolReference.html">Service Archiver</a>.</p> | |
<p> </p> | |
<h2><a name="Advanced_Topics"></a>Advanced Topics</h2> | |
<ul> | |
<li><p style="margin-bottom: 0in"><a href="rest-ws.html">RESTful Web | |
Services</a></p> | |
</li> | |
<li><p style="margin-bottom: 0in"><a href="tcp-transport.html">TCP | |
transport</a></p> | |
</li> | |
<li><p style="margin-bottom: 0in"><a href="mail-transport.html">Mail | |
Transport</a></p> | |
</li> | |
<li><p style="margin-bottom: 0in"><a href="http-transport.html">HTTP | |
Transports</a></p> | |
</li> | |
<li><p><a href="mtom-guide.html">MTOM with Axis2</a></p> | |
</li> | |
<li><p><a href="security-module.html">Securing SOAP Messages with WSS4J</a></p> | |
</li> | |
</ul> | |
</body> | |
</html> |