<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<html>
<head>
  <meta http-equiv="content-type" content="">
  <title>Axis2 integration with the Spring Framework</title>
  <link href="../css/axis-docs.css" rel="stylesheet" type="text/css" media="all" />
</head>

<body lang="en">
<h1>Axis2 Integration With The Spring Framework</h1>

<p>This document is a guide on how to use Axis2 with the Spring Framework</p>

<h2>Content</h2>
<ul>
  <li><a href="#1">Introduction</a></li>
  <li><a href="#2">Configuring Axis2 to be Spring aware</a>
    <ul>
      <li><a href="#21">Programming Model</a></li>
      <li><a href="#22">Simple Spring config example</a></li>
      <li><a href="#23">With a ServletContext </a></li>
      <li><a href="#24">Without a ServletContext</a></li>
      <li><a href="#25">Putting it all together</a></li>
      <li><a href="#26">Spring inside an AAR </a>
        <ul>
          <li><a href="#261">The Spring inside an AAR layout</a></li>
          <li><a href="#262">The Spring inside an AAR init class</a></li>
          <li><a href="#263">Known issues running Spring inside the AAR</a></li>
        </ul>
      </li>
    </ul>
  </li>
</ul>
<a name="1"></a>

<h2>Introduction</h2>

<p>The idea behind Axis2 and Spring integration is that Axis2 simply needs to
have Spring supply one of its pre-loaded beans to the Axis2 Message
Receiver defined in the AAR services.xml . While Axis2 typically uses
reflection to instantiate the ServiceClass defined in the services.xml that
the Message Receiver will use, alternatively one can define a
ServiceObjectSupplier that will supply the Object.</p>

<p>This guide will show how to use two separate ServiceObjectSupplier classes
that are part of the Axis2 standard distribution: One for use with a ServletContext, 
and one without. Once configured, the web service itself acts like
any other Spring wired bean. These Spring beans can be loaded any way desired, 
as Axis2 has no configuration file dependencies from Spring. Spring 
versions 1.2.6, 1.2.8 and 2.0 have been tested, but probably any version would 
work as only core functionality is required.</p>

<p>This guide assumes some basic knowledge of Axis2. See the <a
href="userguide.html">User's Guide</a> for more information.</p>
<a name="2"></a>

<h2>Configuring Axis2 to be Spring Aware</h2>
<a name="21"></a>

<h3>Programming Model</h3>

<p>From an Axis2 standpoint, two hooks are needed to be placed into the AAR
services.xml: The ServiceObjectSupplier that hooks Axis2 and Spring together,
and the name of Spring bean that Axis2 will use as the service. All Message
Receivers are currently supported, as would be any Message Receiver that
extends org.apache.axis2.receivers.AbstractMessageReceiver .</p>
<a name="22"></a>

<h3>Simple Spring Config Example</h3>

<p>For the purpose of this example, and for no other reason besides
simplicity, we'll configure Spring via a WAR file's web.xml. Lets add a
context-param and a listener:</p>
<pre>&lt;listener&gt;
        &lt;listener-class&gt;org.springframework.web.context.ContextLoaderListener&lt;/listener-class&gt;
&lt;/listener&gt;
&lt;context-param&gt;
      &lt;param-name&gt;contextConfigLocation&lt;/param-name&gt;
      &lt;param-value&gt;/WEB-INF/applicationContext.xml&lt;/param-value&gt;
    &lt;/context-param&gt;</pre>

<p>Next we will show two examples of Spring's /WEB-INF/applicationContext.xml
referenced in the web.xml listener -  one using a ServletContext, and one
without.</p>
<a name="23"></a>

<h3>With a ServletContext</h3>

<p>This 'with a ServletContext' example applicationContext.xml should be
familiar to any Spring user:</p>
<pre> &lt;?xml version="1.0" encoding="UTF-8"?&gt;
&lt;!DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN//EN" "http://www.springframework.org/dtd/spring-beans.dtd"&gt;

&lt;beans&gt;
  &lt;!-- Axis2 Web Service, but to Spring, its just another bean that has dependencies --&gt;
  &lt;bean id="springAwareService" class="spring.SpringAwareService"&gt;
    &lt;property name="myBean" ref="myBean"/&gt;
  &lt;/bean&gt;

  &lt;!-- just another bean / interface with a wired implementation, that's injected by Spring
          into the Web Service --&gt;
   &lt;bean id="myBean" class="spring.MyBeanImpl"&gt;
     &lt;property name="val" value="Spring, emerge thyself" /&gt;
  &lt;/bean&gt;
&lt;/beans&gt;</pre>

<p>If the service is running in a Servlet Container, i.e., Axis2 will be able
to get a hold of ServletContext, the services.xml for the example would be
using SpringServletContextObjectSupplier such as:</p>
<pre> &lt;service name="SpringAwareService"&gt;
    &lt;description&gt;
        simple spring example
    &lt;/description&gt;
    &lt;parameter name="ServiceObjectSupplier" locked="false"&gt;org.apache.axis2.extensions.spring.receivers.SpringServletContextObjectSupplier&lt;/parameter&gt;
    &lt;parameter name="SpringBeanName" locked="false"&gt;springAwareService&lt;/parameter&gt;
    &lt;operation name="getValue"&gt;
        &lt;messageReceiver class="org.apache.axis2.receivers.RawXMLINOutMessageReceiver"/&gt;
    &lt;/operation&gt;
&lt;/service&gt; </pre>

<p>While the above example uses RawXMLINOutMessageReceiver as its
messageReceiver class, all Message Receivers are currently supported, as
would be any Message Receiver that extends
org.apache.axis2.receivers.AbstractMessageReceiver .</p>
<a name="24"></a>

<h3>Without a ServletContext</h3>

<p>In the case Axis2 can't get a ServletContext, ie another transport or running inside the AAR etc, 
you have the option of defining a bean that takes advantage of Spring's internal abilities
(ApplicationContextAware interface, specifically) to provide an Application
Context to Axis2, with a bean ref 'applicationContext' :</p>
<pre>&lt;?xml version="1.0" encoding="UTF-8"?&gt;
&lt;!DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN//EN" "http://www.springframework.org/dtd/spring-beans.dtd"&gt;

&lt;beans&gt;
  &lt;!-- Configure spring to give a hook to axis2 without a ServletContext --&gt;
  &lt;bean id="applicationContext" 
    class="org.apache.axis2.extensions.spring.receivers.ApplicationContextHolder" /&gt;

  &lt;!-- Axis2 Web Service, but to Spring, its just another bean that has dependencies --&gt;
  &lt;bean id="springAwareService"
        class="spring.SpringAwareService"&gt;
    &lt;property name="myBean" ref="myBean" /&gt;
  &lt;/bean&gt;

  &lt;!-- just another bean with a wired implementation, that's injected by Spring 
          into the Web Service --&gt;
   &lt;bean id="myBean"
        class="spring.MyBeanImpl"&gt;
     &lt;property name="val" value="Spring, emerge thyself" /&gt;
  &lt;/bean&gt;
&lt;/beans&gt;</pre>

<p>If the service is _NOT_ running in a Servlet Container, i.e., Axis2 will
_NOT_ be able to get a hold of ServletContext or you prefer not to, the services.xml for the
example would be using SpringAppContextAwareObjectSupplier such as:</p>
<pre> &lt;service name="SpringAwareService"&gt;
    &lt;description&gt;
        simple spring example
    &lt;/description&gt;
    &lt;parameter name="ServiceObjectSupplier" locked="false"&gt;org.apache.axis2.extensions.spring.receivers.SpringAppContextAwareObjectSupplier&lt;/parameter&gt;
    &lt;parameter name="SpringBeanName" locked="false"&gt;springAwareService&lt;/parameter&gt;
    &lt;operation name="getValue"&gt;
        &lt;messageReceiver class="org.apache.axis2.receivers.RawXMLINOutMessageReceiver"/&gt;
    &lt;/operation&gt;
&lt;/service&gt; </pre>

<p>While the above example uses RawXMLINOutMessageReceiver as its
messageReceiver class, all Message Receivers are currently supported, as
would be any Message Receiver that extends
org.apache.axis2.receivers.AbstractMessageReceiver .</p>

<p>In a 'without a ServletContext' environment, one way you could load the
applicationContext.xml file is in a place that will be run once, upon
start-up, execute:</p>
<pre>import org.springframework.context.support.ClassPathXmlApplicationContext;

 public void createSpringAppCtx(ClassLoader cl)
            throws Exception {

    ClassPathXmlApplicationContext ctx = new
      ClassPathXmlApplicationContext(new String[] {Constants.MY_PATH +
      "spring/applicationContext.xml"}, false);
           ctx.setClassLoader(cl);
           ctx.refresh();</pre>
} <a name="25"></a>

<h3>Putting It All Together</h3>

<p>From here, its just standard Axis2 coding, only now the service has Spring
wiring capabilities. The implementation is the same whether using either
SpringServletContextObjectSupplier or SpringAppContextAwareObjectSupplier.
The service is below:</p>
<pre>package spring;

import org.apache.axiom.om.OMAbstractFactory;
import org.apache.axiom.om.OMElement;
import org.apache.axiom.om.OMFactory;
import org.apache.axiom.om.OMNamespace;
import org.apache.axiom.om.OMText;

public class SpringAwareService {

    private MyBean myBean = null;

    //spring 'injects' this implementation
    public void setMyBean(MyBean myBean) {
            this.myBean = myBean;
    }

    // The web service
    public OMElement getValue(OMElement ignore) {
            OMFactory factory=
                OMAbstractFactory.getOMFactory();
            OMNamespace payloadNs= factory.createOMNamespace(
                "http://springExample.org/example1", "example1");
            OMElement payload =
                factory.createOMElement("string", payloadNs);
            OMText response = factory.createOMText(this.myBean.emerge());
            payload.addChild(response);
            return payload;
    }
} </pre>

<p>For those new to Spring, one of the ideas is that you program to an
Interface, and the implementation is pluggable. This idea is referenced in
the Spring config file above. Below is the interface:</p>
<pre>package spring;

/** Interface for Spring aware Bean */
public interface MyBean {
         String emerge();
}</pre>

<p>Here's the implementation:</p>
<pre>/** Spring wired implementation */
public class MyBeanImpl implements MyBean {

    String str = null;
    // spring 'injects' this value
    public void setVal(String s) {
        str = s;
    }
    // web service gets this value
    public String emerge() {
        return str;
    }
}</pre>

<p>Lastly here's the client - not really necessary for the example, other
than for completeness:</p>
<pre>package client;

import java.io.StringWriter;

import javax.xml.stream.XMLOutputFactory;

import org.apache.axiom.om.OMAbstractFactory;
import org.apache.axiom.om.OMElement;
import org.apache.axiom.om.OMFactory;
import org.apache.axiom.om.OMNamespace;
import org.apache.axis2.addressing.EndpointReference;
import org.apache.axis2.client.Options;
import org.apache.axis2.client.ServiceClient;

public class TestClient {
    private static EndpointReference targetEPR =
        new EndpointReference(
               "http://localhost:8080/axis2/services/SpringAwareService");

    /**
     * Simple axis2 client.
     *
     * @param args Main
     */
    public static void main(String[] args) {
        try {
            OMFactory factory = OMAbstractFactory.getOMFactory();
            OMNamespace omNs = factory.createOMNamespace(
                        "http://springExample.org/example1", "example1");

            OMElement method = factory.createOMElement("getValue", omNs);
            OMElement value = factory.createOMElement("Text", omNs);
            value.addChild(factory.createOMText(value, "Some String "));
            method.addChild(value);

            ServiceClient serviceClient = new ServiceClient();

            Options options = new Options();
            serviceClient.setOptions(options);
            options.setTo(targetEPR);

            //Blocking invocation
            OMElement result = serviceClient.sendReceive(method);

            StringWriter writer = new StringWriter();
            result.serialize(XMLOutputFactory.newInstance()
                    .createXMLStreamWriter(writer));
            writer.flush();

            System.out.println("Response: " + writer.toString());
        } catch (Exception ex) {
            ex.printStackTrace();
        }
    }
} </pre>

<p>The examples above assumes that both the spring framework jar and the axis2-spring-*.jar 
are under WEB-INF/lib. In such a case, the classes shown in this tutorial need to be placed 
in a JAR under WEB-INF/lib. In this example the JAR layout is:</p>
    <source><pre>./mySpring.jar
./META-INF
./META-INF/MANIFEST.MF
./spring
./spring/MyBean.class
./spring/MyBeanImpl.class
./spring/SpringAwareService.class
</pre> </source>

<p>Since all the user classes are in mySpring.jar in this example, the AAR merely contains the 
services.xml file:</p>

    <source>
    <pre>./springExample.aar
./META-INF
./META-INF/MANIFEST.MF
./META-INF/services.xml
</pre> </source>

<p>To run this example, make sure you have the axis2-spring*.jar that comes
from the axis2-std-*-bin distro in the server side WEB-INF/lib, as well as
the appropriate Spring jar - most will use the full spring.jar, but the
minimum requirements are spring-core, spring-beans, spring-context and
spring-web. Running the client, you should see this output:</p>
<pre>Response: &lt;example1:string xmlns:example1="http://springExample.org/example1" 
  xmlns:tns="http://ws.apache.org/axis2"&gt;Spring, emerge thyself&lt;/example1:string&gt;</pre>
<a name="26"></a>

<h3>Spring Inside an AAR</h3>

<p>Frequently Axis2 users wish to run Spring inside the AAR. Here we show you
how. There are four points to be aware of:</p>

<p>(A) You need to configure Spring to use the Axis2 Service Classloader. See the 
  <a href="#263">Known issues running Spring inside the AAR</a> area. </p>

<p>(B) Its up to you to load Spring, though we give an example below.</p>

<p>(C) For reasons such as classloader isolation the
SpringAppContextAwareObjectSupplier is the best choice.</p>

<p>(D) The springframework jar and axis2-spring-*.jar will be placed inside
the AAR under the lib directory. Please MOVE the axis2-spring-*.jar from WEB-INF/lib to inside 
the AAR, as shown below - it will NOT work otherwise. </p>
<ul>
  <li><strong><a name="261"></a>The Spring inside an AAR layout</strong>
</ul>
    <source>
    <pre>./springExample.aar
./META-INF
./META-INF/MANIFEST.MF
./META-INF/services.xml
./applicationContext.xml
./lib
./lib/axis2-spring-SNAPSHOT.jar
./lib/spring.jar
./spring
./spring/MyBean.class
./spring/MyBeanImpl.class
./spring/SpringAwareService.class
./spring/SpringInit.class </pre> </source>

<p>As explained in the <a href="#24">Without a ServletContext</a> section, likewise the
'Spring inside an AAR' config needs to hook Axis2 and Spring together via a Spring bean. 
Place the following in your Spring config file:</p>
<pre>
  &lt;!-- Configure spring to give a hook to axis2 without a ServletContext --&gt;
  &lt;bean id="applicationContext" 
    class="org.apache.axis2.extensions.spring.receivers.ApplicationContextHolder" /&gt;
</pre>
<ul>
  <li><strong><a name="262"></a>The Spring inside an AAR init class</strong></li>
</ul>
<p>One way to initialize Spring inside the AAR is to use the 
org.apache.axis2.engine.ServiceLifeCycle interface. Here we give an example:</p>
    <source><pre>package spring;

import org.apache.axis2.engine.ServiceLifeCycle;
import org.apache.axis2.context.ConfigurationContext;
import org.apache.axis2.description.AxisService;
import org.springframework.context.support.ClassPathXmlApplicationContext;

public class SpringInit implements ServiceLifeCycle {
	
    /**
     * This will be called during the deployement time of the service. 
     * irrespective
     * of the service scope this method will be called
     */
    public void startUp(ConfigurationContext ignore, AxisService service) {
 
        try {
            System.out.println("Starting spring init");
            ClassLoader classLoader = service.getClassLoader();
            ClassPathXmlApplicationContext appCtx = new
            ClassPathXmlApplicationContext(new String[] {"applicationContext.xml"}, false);
                appCtx.setClassLoader(classLoader);
                appCtx.refresh();
            System.out.println("spring loaded");
        } catch (Exception ex) {
            ex.printStackTrace();
        }
    }

    /**
     * This will be called during the system shut down time. 
     * irrespective
     * of the service scope this method will be called
     */
    public void shutDown(ConfigurationContext ctxIgnore, AxisService ignore) {
    }
}</pre>
    </source>
    <p>Here's the services.xml that now includes SpringInit and the SpringAwareService 
    shown above. There is also the composite parameter which is needed when loading 
    Spring in the AAR - see the <a href="#263">Known issues running Spring inside the AAR</a>
    area. </p>
    <source><pre>&lt;serviceGroup&gt;
  &lt;!-- Invoke SpringInit on server startup and shutdown --&gt;
  &lt;service name="SpringAwareService" class="spring.SpringInit"&gt;
    &lt;description&gt;
         simple spring example - inside the AAR
    &lt;/description&gt;
    &lt;!-- need the TCCL param when using spring inside the AAR --&gt;
    &lt;parameter name="ServiceTCCL" locked="false"&gt;composite&lt;/parameter&gt;
    &lt;parameter name="ServiceObjectSupplier" locked="false"&gt;org.apache.axis2.extensions.spring.receivers.SpringAppContextAwareObjectSupplier&lt;/parameter&gt;
    &lt;parameter name="SpringBeanName" locked="false"&gt;springAwareService&lt;/parameter&gt;
    &lt;operation name="getValue"&gt;
        &lt;messageReceiver class="org.apache.axis2.receivers.RawXMLINOutMessageReceiver"/&gt;
    &lt;/operation&gt;
  &lt;/service&gt;
&lt;/serviceGroup&gt;</pre>
</source>
<ul>
  <li>
    <strong><a name="263"></a>Known issues running Spring inside the AAR</strong>
  </li>
</ul>
    <p>The Axis2 classloader strategy by default does not permit Spring to run inside the AAR. To 
    allow Spring to run inside the AAR, the 'composite' parameter is used in the services.xml as 
    shown in the example above. The behavior of 'composite' was the default in the development 
    cycle in between 1.0 and 1.1, but it resulted in the JIRA issue AXIS2-1214 - essentially 
    problems with getting an initContext.lookup() handle inside the AAR. Spring users typically 
    have little desire to use initContext.lookup() however, as they get their Datasources via 
    org.springframework.jdbc.datasource.DriverManagerDataSource in an xml file or with annotations. 
    For ejb home references and the like, Spring provides JndiObjectFactoryBean. While fully testing 
    JndiObjectFactoryBean with ejb has not been done yet - if you do, please send a message 
    to the axis users list - Datasources via Spring inside the AAR have been tested. Basically 
    it works as typically done with Spring, though if you are passing Hibernate XML files you need 
    to put them in a place where Spring will find them. The most flexible way is as follows, using 
    logging in DEBUG mode to see where Spring will look in your jar / class locations: </p>
    <source><pre>
    &lt;bean id="mySessionFactory" class="org.springframework.orm.hibernate3.LocalSessionFactoryBean"&gt;
                &lt;property name="mappingLocations"&gt;
                   &lt;value&gt;classpath*:**/MyEntity.hbm.xml&lt;/value&gt;
                &lt;/property&gt;
                ...
    &lt;/bean&gt; 
</pre> </source>
</body>
</html>