Creating a Hello World JBI Binding Component
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NOTE: Before beginning this tutorial, please take the time to read the FAQ entry titled Should I Create My Own JBI Components?. It is very important that you understand the reason for developing a JBI binding component and this FAQ entry will explain this. |
This tutorial describes how to create a very simple Hello World style of JBI binding component. This tutorial is as minimalistic as possible so as to focus on key concepts and not drown in details. The Hello World binding component will respond to all requests with the message:
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The following sections will walk through the creation, packaging, testing and deployment of the Hello World binding component.
Prerequisites
- Maven 2.0.4 7 or higher
- If you have never used Maven previously the Maven Getting Started Guide explains some valuable concepts surrounding Maven
- ServiceMix 3.2.1 -incubating-SNAPSHOT or higher
- See the ServiceMix downloads to grab a nightly build as ServiceMix 3.1 has not yet been released
- A broadband internet connection so Maven can automatically download dependencies
A Very Brief Introduction to Java Business Integration
The Java Business Integration (JBI) spec provides a standards-based, service-oriented approach to application integration through the use of an abstract messaging model, without reference to a particular protocol or wire encoding. JBI introduces the concepts of Binding Components (BCs), Service Engines (SEs) to Service Units (SUs) and Service Assemblies (SAs) to define an architecture for vendor-neutral pluggable components. The purpose of this architecture is to provide standards-based interoperability amongst components/services.
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Now let's move on to creating the Maven projects for the Hello World binding component.
Creating a Maven Project For the JBI BC
The focus of this section is on the creation of a JBI binding component. For this task, a Maven archetype will be used to create a Maven project skeleton to house the component. Maven archetypes are templates for Maven projects that jumpstart project creation via the automation of repetitive tasks by following standard conventions. The result of using an archetype to create a Maven project is a directory structure, a Maven POM file and, depending on the archetype being used, sometimes Java objects and JUnit tests.
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$ mkdir hello-world-smx $ cd hello-world-smx |
2) Use the servicemix-servicebinding-enginecomponent Maven archetype to generate a Maven project for the component.
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$ mvn archetype:create \ |
The command above will create a directory named hello-world-bc-su
that houses a Maven project for the JBI service engine being created here. The name of the directory is taken from the artifactId
parameter.
The first three parameters to the mvn
command (-DarchetypeGroupId=org.apache.servicemix.tooling -DarchetypeArtifactId=servicemix-binding-component -DarchetypeVersion=3.2.1-incubating-SNAPSHOT) identify which Maven archetype to use for the archetype:create
goal, while the last two parameters (-DgroupId=org.apache.servicemix.samples.helloworld.bc -DartifactId=hello-world-bc-su) uniquely identify the Maven project that is being generated. The groupId
is used as the Java package and the artifactId
is used as the project name. Therefore, only alphanumeric characters are valid values for the groupId
and artifactId
parameters.
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The value of the |
The output from executing the archetype:create
goal is shown below:
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[INFO] Scanning for projects... [INFO] ReactorSearching buildrepository order: [INFO] A custom project [INFO] A custom project [INFO] Hello World JBI Component [INFO] Searching repository for plugin with prefix: 'archetype'. [INFO] ---------for plugin with prefix: 'archetype'. [INFO] ------------------------------------------------------------------------------ [INFO] Building HelloMaven WorldDefault JBI ComponentProject [INFO] task-segment: [archetype:create] (aggregator-style) [INFO] ---------------------------------------------------------------------------- [INFO] Setting property: classpath.resource.loader.class => 'org.codehaus.plexus.velocity.ContextClassLoaderResourceLoader'. [INFO] Setting property: velocimacro.messages.on => 'false'. [INFO] Setting property: resource.loader => 'classpath'. [INFO] Setting property: resource.manager.logwhenfound => 'false'. [INFO] ************************************************************** [INFO] Starting Jakarta Velocity v1.4 [INFO] RuntimeInstance initializing. [INFO] Default Properties File: org/apache/velocity/runtime/defaults/velocity.properties [INFO] Default ResourceManager initializing. (class org.apache.velocity.runtime.resource.ResourceManagerImpl) [INFO] Resource Loader Instantiated: org.codehaus.plexus.velocity.ContextClassLoaderResourceLoader [INFO] ClasspathResourceLoader : initialization starting. [INFO] ClasspathResourceLoader : initialization complete. [INFO] ResourceCache : initialized. (class org.apache.velocity.runtime.resource.ResourceCacheImpl) [INFO] Default ResourceManager initialization complete. [INFO] Loaded System Directive: org.apache.velocity.runtime.directive.Literal [INFO] Loaded System Directive: org.apache.velocity.runtime.directive.Macro [INFO] Loaded System Directive: org.apache.velocity.runtime.directive.Parse [INFO] Loaded System Directive: org.apache.velocity.runtime.directive.Include [INFO] Loaded System Directive: org.apache.velocity.runtime.directive.Foreach [INFO] Created: 20 parsers. [INFO] Velocimacro : initialization starting. [INFO] Velocimacro : adding VMs from VM library template : VM_global_library.vm [ERROR] ResourceManager : unable to find resource 'VM_global_library.vm' in any resource loader. [INFO] Velocimacro : error using VM library template VM_global_library.vm : org.apache.velocity.exception.ResourceNotFoundException: Unable to find resource 'VM_global_library.vm' [INFO] Velocimacro : VM library template macro registration complete. [INFO] Velocimacro : allowInline = true : VMs can be defined inline in templates [INFO] Velocimacro : allowInlineToOverride = false : VMs defined inline may NOT replace previous VM definitions [INFO] Velocimacro : allowInlineLocal = false : VMs defined inline will be global in scope if allowed. [INFO] Velocimacro : initialization complete. [INFO] Velocity successfully started. [INFO] [archetype:create] [INFO] Defaulting package to group ID: org.apache.servicemix.samples.helloworld.bc [INFO] ---------------------------------------------------------------------------- [INFO] Using following parameters for creating Archetype: servicemix-binding-component:3.2.1-incubating-SNAPSHOT [INFO] ---------------------------------------------------------------------------- [INFO] Parameter: groupId, Value: org.apache.servicemix.samples.helloworld.bc [INFO] Parameter: packageName, Value: org.apache.servicemix.samples.helloworld.bc [INFO] Parameter: basedir, Value: /Users/bsnyder/src/hello-world-smx [INFO] Parameter: package, Value: org.apache.servicemix.samples.helloworld.bc [INFO] Parameter: version, Value: 1.0-SNAPSHOT [INFO] Parameter: artifactId, Value: hello-world-bc-su [WARNING] org.apache.velocity.runtime.exception.ReferenceException: reference : template = archetype-resources/pom.xml [line 6885,column 16] : ${servicemix-version} is not a valid reference. [WARNING] org.apache.velocity.runtime.exception.ReferenceException: reference : template = archetype-resources/pom.xml [line 7390,column 16] : ${servicemix-version} is not a valid reference. [WARNING] org.apache.velocity.runtime.exception.ReferenceException: reference : template = archetype-resources/pom.xml [line 97115,column 18] : ${xbean-version} is not a valid reference. [INFO] ********************* End of debug info from resources from generated POM *********************** [INFO] Archetype created in dir: /Users/bsnyder/src/hello-world-smx/hello-world-bc-su [INFO] ------------------------------------------------------------------------ [INFO] BUILD SUCCESSFUL [INFO] ------------------------------------------------------------------------ [INFO] Total time: 23 seconds [INFO] Finished at: MonTue JanMar 1506 1318:3527:4408 MST 2007 [INFO] Final Memory: 5M4M/10M8M [INFO] ------------------------------------------------------------------------ |
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The maven-archetype-plugin 1.0-alpha4 or above is required for this tutorial. When an older version is installed, a build error will occur. The version of this plugin can be checked by verifying the name of the following directories:
In case the only version available of the maven-archetype-plugin is an older one, a minimal
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Compiling the Project
Since we just created this project, we should first compile it just to make sure nothing is wrong with what the archetype generated. To compile, package and test the project, execute the following command from the command-line:
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$ cd ./hello-world-bc-su
$ mvn install
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This command should produce the following output:
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[INFO] Scanning for projects... [INFO] artifact org.apache.servicemix.tooling:jbi-maven-plugin: checking for updates from apache.incubating [INFO] -------------------------------------------------------------------------------- [INFO] Building A custom project [INFO] task-segment: [install] [INFO] ---------------------------------------------------------------------------- [INFO] artifact[xbean:mapping {execution: default}] Checking: org.apache.maven.plugins:maven-install-plugin: checking for updates from apache.incubating Downloading: http://people.apache.org/repo/m2-incubating-repository/xml-security/xmlsec/1.3.0/xmlsec-1.3.0.pom [WARNING] Unable to get resource from repository apache.incubating (http://people.apache.org/repo/m2-incubating-repository) Downloading: http://repo.mergere.com/maven2/xml-security/xmlsec/1.3.0/xmlsec-1.3.0.pom [WARNING] Unable to get resource from repository central (http://repo1.maven.org/maven2) Downloading: http://people.apache.org/repo/m2-incubating-repository/wss4j/wss4j/1.5.0/wss4j-1.5.0.pom [WARNING] Unable to get resource from repository apache.incubating (http://people.apache.org/repo/m2-incubating-repository) Downloading: http://repo.mergere.com/maven2/wss4j/wss4j/1.5.0/wss4j-1.5.0.pom [WARNING] Unable to get resource from repository central (http://repo1.maven.org/maven2) [INFO] [xbean:mapping {execution: default}] Checking: org.apache.servicemix.samples.helloworld.MyComponent Checking: org.apache.servicemix.samples.helloworld.MyConsumerEndpoint Checking: org.apache.servicemix.samples.helloworld.MyProviderEndpoint [INFO] Generating META-INF properties .servicemix.samples.helloworld.bc.MyComponent Checking: org.apache.servicemix.samples.helloworld.bc.MyConsumerEndpoint Checking: org.apache.servicemix.samples.helloworld.bc.MyProviderEndpoint [INFO] Generating META-INF properties file: /Users/bsnyder/src/hello-world-smx/hello-world-bc/target/xbean/META-INF/services/org/apache/xbean/spring/http/ org.apache.servicemix.samples.helloworld.bc/1.0 for namespace: http://org.apache.servicemix.samples.helloworld.bc/1.0 [INFO] Generating Spring 2.0 handler mapping: /Users/bsnyder/src/hello-world-smx/hello-world-bc/target/xbean/META-INF/spring.handlers for namespace: http://org.apache.servicemix.samples.helloworld.bc/1.0 [INFO] Generating Spring 2.0 schema mapping: /Users/bsnyder/src/hello-world-smx/hello-world-bc/target/xbean/META-INF/spring.schemas for namespace: http://org.apache.servicemix.samples.helloworld.bc/1.0 [INFO] Generating HTML documentation file: /Users/bsnyder/src/hello-world-smx/hello-world-bc-su/target/xbean/META-INF/services/org/apache/xbean/spring/http/ org.apache.servicemix.samples.helloworld/1.0hello-world-bc.xsd.html for namespace: http://org.apache.servicemix.samples.helloworld.bc/1.0 [INFO] Generating Spring 2.0 handler mapping: XSD file: /Users/bsnyder/src/hello-world-smx/hello-world-bc-su/target/xbean/META-INF/spring.handlers hello-world-bc.xsd for namespace: http://org.apache.servicemix.samples.helloworld.bc/1.0 [INFO] Generating SpringWIKI 2.0 schema mappingdocumentation file: /Users/bsnyder/src/hello-world-smx/hello-world-bc-su/target/xbean/META-INF/spring.schemas hello-world-bc.xsd.wiki for namespace: \http://org.apache.servicemix.samples.helloworld.bc/1.0 [INFO] Generating HTML documentation file: /Users/bsnyder/src/hello-world-smx/hello-world-bc-su/target/xbean/hello-world-bc-su.xsd.html for namespace: http://Warning, could not load class: org.apache.servicemix.samples.helloworld/1.0[INFO] Generating XSD file: /Users/bsnyder/src/hello-world-smx/hello-world-bc-su/target/xbean/hello-world-bc-su.xsd for namespace: http://.bc.MyEndpointType: java.lang.ClassNotFoundException: org.apache.servicemix.samples.helloworld/1.bc.0MyEndpointType [INFO] Generating WIKI documentation file: /Users/bsnyder/src/hello-world-smx/hello-world-bc-su/target/xbean/hello-world-bc-su.xsd.wiki for namespace: http://org.apache.servicemix.samples.helloworld/1.0Warning, could not load class: org.apache.servicemix.samples.helloworld.MyEndpointType: java.lang.ClassNotFoundException: org.apache.servicemix.samples.helloworld.MyEndpointType [INFO] ...done. [INFO] [jbi:generate-jbi-component-descriptor] [INFO] Generating jbi.xml...done. [INFO] [jbi:generate-jbi-component-descriptor] [INFO] Generating jbi.xml [WARNING] Attempting to build MavenProject instance for Artifact of type: jar; constructing POM artifact instead. [WARNING] Attempting to build MavenProject instance for Artifact of type: jar; constructing POM artifact instead. [WARNING] Attempting to build MavenProject instance for Artifact of type: jar; constructing POM artifact instead. [WARNING] Attempting to build MavenProject instance for Artifact of type: jar; constructing POM artifact instead. [INFO] [resources:resources] [INFO] Using default encoding to copy filtered resources. [INFO] [compiler:compile] [INFO] Compiling 5 source files to /Users/bsnyder/src/hello-world-smx/hello-world-bc-su/target/classes [INFO] [resources:testResources] [INFO] Using default encoding to copy filtered resources. [INFO] [compiler:testCompile] [INFO] Compiling 1 source file to /Users/bsnyder/src/hello-world-smx/hello-world-bc-su/target/test-classes [INFO] [surefire:test] [INFO] Surefire report directory: /Users/bsnyder/src/hello-world-smx/hello-world-bc-su//target/surefire-reports ------------------------------------------------------- T E S T S ------------------------------------------------------- Running org.apache.servicemix.samples.helloworld.bc.MySpringComponentTest log4j:WARN No appenders could be found for logger (org.springframework.core.CollectionFactory). log4j:WARN Please initialize the log4j system properly. Tests run: 1, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 1.52431 sec Results : Tests run: 1, Failures: 0, Errors: 0, Skipped: 0 [INFO] [jar:jar] [INFO] Building jar: /Users/bsnyder/src/hello-world-smx/hello-world-bc-su/target/hello-world-bc-su-1.0-SNAPSHOT.jar [INFO] [jbi:jbi-component] [INFO] Generating installer /Users/bsnyder/src/hello-world-smx/hello-world-bc-su/target/hello-world-bc-su-1.0-SNAPSHOT-installer.zip [INFO] Building jar: /Users/bsnyder/src/WARNING] Attempting to build MavenProject instance for Artifact of type: jar; constructing POM artifact instead. [WARNING] Attempting to build MavenProject instance for Artifact of type: jar; constructing POM artifact instead. [WARNING] Attempting to build MavenProject instance for Artifact of type: jar; constructing POM artifact instead. [INFO] Generating installer /Users/bsnyder/src/hello-world-smx/hello-world-bc-su/target/hello-world-bc-1.0-SNAPSHOT-installer.zip [INFO] Building jar: /Users/bsnyder/src/hello-world-smx/hello-world-bc/target/hello-world-bc-su-1.0-SNAPSHOT-installer.zip [INFO] [install:install] [INFO] Installing /Users/bsnyder/src/hello-world-smx/hello-world-bc-su/target/hello-world-bc-su-1.0-SNAPSHOT.jar to /Users/bsnyder/.m2/repository/org/apache/servicemix/samples/helloworld/bc/hello-world-bc-su/1.0-SNAPSHOT/hello-world-bc-su-1.0-SNAPSHOT.jar [INFO] Installing /Users/bsnyder/src/hello-world-smx/hello-world-bc-su/target/xbean/hello-world-bc-su.xsd to /Users/bsnyder/.m2/repository/org/apache/servicemix/samples/helloworld/bc/hello-world-bc-su/1.0-SNAPSHOT/hello-world-bc-su-1.0-SNAPSHOT.xsd [INFO] Installing /Users/bsnyder/src/hello-world-smx/hello-world-bc-su/target/xbean/hello-world-bc-su.xsd.html to /Users/bsnyder/.m2/repository/org/apache/servicemix/samples/helloworld/bc/hello-world-bc-su/1.0-SNAPSHOT/hello-world-bc-su-1.0-SNAPSHOT-schema.html [INFO] Installing /Users/bsnyder/src/hello-world-smx/hello-world-bc-su/target/hello-world-bc-su-1.0-SNAPSHOT-installer.zip to /Users/bsnyder/.m2/repository/org/apache/servicemix/samples/helloworld/bc/hello-world-bc-su/1.0-SNAPSHOT/hello-world-bc-su-1.0-SNAPSHOT-installer.zip [INFO] ------------------------------------------------------------------------ [INFO] BUILD SUCCESSFUL [INFO] ------------------------------------------------------------------------ [INFO] Total time: 1615 seconds [INFO] Finished at: MonTue JanMar 1506 2118:4729:51 MST 2007 [INFO] Final Memory: 13M/31M28M [INFO] ------------------------------------------------------------------------ |
Your output may look slightly different because Maven will download the required artifacts. Again, the key here is to make sure you see BUILD SUCCESSFUL. This means that the project skeleton created by the archetype was compiled, packaged and tested successfully. Now we just need to add some custom functionality.
Creating the JBI Component
Before we create any custom functionality, let's first examine some of the items generated by the servicemix-servicebinding-engine component Maven archetype in this simple component we're developing. These classes extend class from either the JBI spec APIs or from the servicemix-common
package.
pom.xml
- This is the Maven POM] file. This XML file contains all the metadata related to the project so Maven can carry out its functionality.
src/main/java/org/apache/servicemix/samples/bc/MyBootstrap.java
- Implementsjavax.jbi.component.Boostrap
which is called by the JBI container as part of the component lifecycle (i.e.g, when the component is installed and uninstalled). This is where you place logic to set up and tear down things when the component is started and stopped. This class is no longer needed.
src/main/java/org/apache/servicemix/samples/bc/MyComponent.java
- Extends theDefaultComponent
, a convenience class that makes creating JBI components much easier and provides some additional lifecycle management of components for the BC when it's deployed to the JBI container. This class should be fleshed out by overriding methods in theDefaultComponent
to configure and initialize the component.
MyConsumerEndpointsrc/main/java/org/apache/servicemix/samples/bc/MyConsumerEndpoint.java
- ExtendsConsumerEndpoint
and implementsMyEndpointType
. If you'd like to create a BC that fulfills the consumer role, implement theprocess()
method in this class.
src/main/java/org/apache/servicemix/samples/bc/MyEndpointType.java
- This class is simply an interface marker for Apache XBean so it can generate an XML schema document.
src/main/java/org/apache/servicemix/samples/bc/MyProviderEndpoint.java
- ExtendsProviderEndpoint
and implementsMyEndpointType
. If you'd like to create a BC that fulfills the provider role, depending on the MEP being supported, you will need to implement theprocessInOnly()
method or theprocessInOut()
method in this class.
src/main/java/org/apache/servicemix/samples/bc/MyEndpointType.java
- This is a marker interface used by XBean so it can generate a XML schema.
src/test/java/org/apache/servicemix/samples/bc/MySpringComponentTest.java
- A simple JUnit test class that extends a helper classMySpringComponentTest.java
- A simple JUnit test class that extends a helper class to make configuring ServiceMix very easy.
src/test/resources/spring.xml
- The A very simple and generic ServiceMix configuration file for use with theMySpringComponentTest
.
Now that we've gotten a bird's eye view of what we're working with, let's proceed to adding the custom functionality.
Adding Custom Functionality
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It is at this stage that you should employ the use of an IDE. An IDE can dramatically reduce the work necessary to import clases, override methods and so much more. Because Maven can generate project files for Eclipse and IntelliJ IDEA, either one can be used. Throughout this tutorial, Eclipse will be used. To generate project files for Eclipse, execute the Maven |
This is a work in progress. I will finish this up very soon.
Testing the Hello World Binding Component
Thanks to the archetype, testing the component is very easy because it already created a test. The only change we'll make is to the string being sent by the client code. In the src/test/java
directory is the org.apache.servicemix.samples.helloworld.bc.MySpringComponentTest
test. Simply open this test and change line #36 from this:
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me.getInMessage().setContent(new StringSource("<hello>world</hello>"));
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to something more meaningful, like this:
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me.getInMessage().setContent(new StringSource("<hello>Ski Colorado!</hello>"));
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To execute the test, simply run the Maven install
goal from within the hello-world-bc-su
directory like so:
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$ mvn install
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Below is the output that will print to the console:
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Before creating custom functionality for the BC, you need to understand the role of a JBI BC. A BC is simply a binding to a service that is external to the JBI normalized message router (NMR) using some type of communications protocol (e.g., FTP, HTTP, JMS, etc.). It's also the responsibility of the BC to handle any conversion of the message format into a normalized message so that can be sent along to the NMR. This is known as message normalization.
Just as an example, if we were to create a BC that uses SNMP as the application layer protocol, the SNMP RFC specifies the message format to be used with particular versions of SNMP. It would be the responsibility of the BC to handle not only the communication via the SNMP protocol but also to handling the marshalling of SNMP messages to/from JBI normalized messages. The BC would simply be a binding to a service external to the NMR that speaks SNMP messages via the SNMP protocol.
More on this later in the tutorial. For now, let's proceed with the custom functionality.
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It is at this stage that you should employ the use of an IDE. An IDE can dramatically reduce the work necessary to import clases, override methods and so much more. Because Maven can easily generate project files for Eclipse or IntelliJ IDEA, either one can be used. Throughout this tutorial, Eclipse will be used. To generate project files for Eclipse, execute the Maven |
The creation of a binding component is dependent upon the role that it will play. BCs are consumers, providers or both. Below are definitions of the two roles as they pertain to BCs:
- Consumer - A consumer BC receives requests from a service external to the JBI container and publishes those requests to the NMR.
- Provider - A provider BC receives requests from the NMR and publishes those requests to a service that is external to the JBI container.
This is why both the MyConsumerEndpoint.java
and the MyProviderEndpoint.java
files exist when using the servicemix-binding-component archetype to create a Maven project. This way the BC that you're creating can play either the consumer role or the provider role or both. For the sake of this tutorial, we will implement the provider role. Let's proceed to implement the provider functionality. To do so, open MyProviderEndpoint.java
and let's take a look at he processInOut()
method as shown below:
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protected void processInOut(MessageExchange exchange, NormalizedMessage in, NormalizedMessage out) throws Exception {
throw new UnsupportedOperationException("Unsupported MEP: " + exchange.getPattern());
}
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One important item of note before we get started is that this tutorial will not actually be accessing any services external to the JBI container. The reason for this is that setting up a service external to the JBI container would dramatically increase the complexity of this tutorial. Instead, we will just simulate such functionality by hard-coding some text to be returned.
The processInOut()
method is just a stub that needs to be populated with our custom functionality. Below is the method body that can be copied and pasted into the method stub add some custom functionality. Following the display of this method, we will pick apart this method a bit to explain the various pieces of logic:
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protected void processInOut(MessageExchange exchange, NormalizedMessage in, NormalizedMessage out) throws Exception {
// Grab the in message
SourceTransformer sourceTransformer = new SourceTransformer();
DOMSource inMessageXml = (DOMSource) sourceTransformer.toDOMSource(in);
// Parse out the actual message content
CachedXPathAPI xpath = new CachedXPathAPI();
Node inMessageNode = xpath.selectSingleNode(inMessageXml.getNode(), "/hello");
String inMessage = inMessageNode.getTextContent();
// Create the out message and set it
String outMessage = "<hello>Message [" + inMessage + "] contains [" + inMessage.getBytes().length + "] bytes</hello>";
out.setContent(new StringSource(outMessage));
}
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Adding this method will require the import of the following classes:
javax.xml.transform.dom.DOMSource
org.apache.servicemix.jbi.jaxp.SourceTransformer
org.apache.servicemix.jbi.jaxp.StringSource
org.apache.xpath.CachedXPathAPI
org.w3c.dom.Node
All of these classes can be found in either the servicemix-core project or its transitive dependencies. If you're using Eclipse, you can tell Eclipse to automatically import them by selecting Source->Organize Imports.
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This tutorial will not be accessing any services external to the JBI container. Instead, we will just simulate such functionality by hard-coding some text to be returned. |
Now let's move on to testing this component and then we'll compile and test it.
Testing the Hello World Binding Component
Thanks to the Maven archetype, testing the component is very easy because it already created a test. The only change we'll make is to the string being sent by the client code. In the src/test/java
directory is the org.apache.servicemix.samples.helloworld.bc.MySpringComponentTest
test. Simply open this test and change line #36 from this:
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me.getInMessage().setContent(new StringSource("<hello>world</hello>"));
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to something more meaningful, like this:
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me.getInMessage().setContent(new StringSource("<hello>Ski Colorado!</hello>"));
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Also, add the following block of code to line # 40 below the comment:
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if (me.getStatus() == ExchangeStatus.ERROR) {
if (me.getError() != null) {
throw me.getError();
} else {
fail("Received ERROR status");
}
} else if (me.getFault() != null) {
fail("Received fault: " + new SourceTransformer().toString(me.getFault().getContent()));
}
System.err.println(new SourceTransformer().toString(me.getOutMessage().getContent()));
client.done(me);
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Though there are no asserts in the test, it is more about seeing visual confirmation of the message being output to the console when running the test. So to compile the source and to execute the test, simply run the Maven install
goal on the command line from within the hello-world-bc
directory like so:
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$ mvn install
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Below is the output that will print to the console:
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[INFO] Scanning for projects...
[INFO] ----------------------------------------------------------------------------
[INFO] Building A custom project
[INFO] task-segment: [install]
[INFO] ----------------------------------------------------------------------------
[INFO] [xbean:mapping {execution: default}]
Checking: org.apache.servicemix.samples.helloworld.bc.MyComponent
Checking: org.apache.servicemix.samples.helloworld.bc.MyConsumerEndpoint
Checking: org.apache.servicemix.samples.helloworld.bc.MyProviderEndpoint
[INFO] Generating META-INF properties file:
/Users/bsnyder/src/hello-world-smx/hello-world-bc/target/xbean/META-INF/services/org/apache/xbean/spring/http/org.apache.servicemix.samples.helloworld.bc/1.0
for namespace: http://org.apache.servicemix.samples.helloworld.bc/1.0
[INFO] Generating Spring 2.0 handler mapping: /Users/bsnyder/src/hello-world-smx/hello-world-bc/target/xbean/META-INF/spring.handlers
for namespace: http://org.apache.servicemix.samples.helloworld.bc/1.0
[INFO] Generating Spring 2.0 schema mapping: /Users/bsnyder/src/hello-world-smx/hello-world-bc/target/xbean/META-INF/spring.schemas
for namespace: http://org.apache.servicemix.samples.helloworld.bc/1.0
[INFO] Generating HTML documentation file: /Users/bsnyder/src/hello-world-smx/hello-world-bc/target/xbean/hello-world-bc.xsd.html
for namespace: http://org.apache.servicemix.samples.helloworld.bc/1.0
[INFO] Generating XSD file: /Users/bsnyder/src/hello-world-smx/hello-world-bc/target/xbean/hello-world-bc.xsd
for namespace: http://org.apache.servicemix.samples.helloworld.bc/1.0
[INFO] Generating WIKI documentation file: /Users/bsnyder/src/hello-world-smx/hello-world-bc/target/xbean/hello-world-bc.xsd.wiki
for namespace: http://org.apache.servicemix.samples.helloworld.bc/1.0
[INFO] ...done.
[INFO] [jbi:generate-jbi-component-descriptor]
[INFO] Generating jbi.xml
[WARNING] Attempting to build MavenProject instance for Artifact of type: jar; constructing POM artifact instead.
[WARNING] Attempting to build MavenProject instance for Artifact of type: jar; constructing POM artifact instead.
[WARNING] Attempting to build MavenProject instance for Artifact of type: jar; constructing POM artifact instead.
[WARNING] Attempting to build MavenProject instance for Artifact of type: jar; constructing POM artifact instead.
[INFO] [resources:resources]
[INFO] Using default encoding to copy filtered resources.
[INFO] [compiler:compile]
[INFO] Nothing to compile - all classes are up to date
[INFO] [resources:testResources]
[INFO] Using default encoding to copy filtered resources.
[INFO] [compiler:testCompile]
[INFO] Nothing to compile - all classes are up to date
[INFO] [surefire:test]
[INFO] Surefire report directory: /Users/bsnyder/src/hello-world-smx/hello-world-bc/target/surefire-reports
-------------------------------------------------------
T E S T S
-------------------------------------------------------
Running org.apache.servicemix.samples.helloworld.bc.MySpringComponentTest
log4j:WARN No appenders could be found for logger (org.springframework.core.CollectionFactory).
log4j:WARN Please initialize the log4j system properly.
<?xml version="1.0" encoding="UTF-8"?>
<hello>Message [Ski Colorado!] contains [13] bytes</hello>
Tests run: 1, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 1.635 sec
Results :
Tests run: 1, Failures: 0, Errors: 0, Skipped: 0
[INFO] [jar:jar]
[INFO] Building jar: /Users/bsnyder/src/hello-world-smx/hello-world-bc/target/hello-world-bc-1.0-SNAPSHOT.jar
[INFO] [jbi:jbi-component]
[WARNING] Attempting to build MavenProject instance for Artifact of type: jar; constructing POM artifact instead.
[WARNING] Attempting to build MavenProject instance for Artifact of type: jar; constructing POM artifact instead.
[WARNING] Attempting to build MavenProject instance for Artifact of type: jar; constructing POM artifact instead.
[INFO] Generating installer /Users/bsnyder/src/hello-world-smx/hello-world-bc/target/hello-world-bc-1.0-SNAPSHOT-installer.zip
[INFO] Building jar: /Users/bsnyder/src/hello-world-smx/hello-world-bc/target/hello-world-bc-1.0-SNAPSHOT-installer.zip
[INFO] [install:install]
[INFO] Installing /Users/bsnyder/src/hello-world-smx/hello-world-bc/target/hello-world-bc-1.0-SNAPSHOT.jar to
/Users/bsnyder/.m2/repository/org/apache/servicemix/samples/helloworld/bc/hello-world-bc/1.0-SNAPSHOT/hello-world-bc-1.0-SNAPSHOT.jar
[INFO] Installing /Users/bsnyder/src/hello-world-smx/hello-world-bc/target/xbean/hello-world-bc.xsd to
/Users/bsnyder/.m2/repository/org/apache/servicemix/samples/helloworld/bc/hello-world-bc/1.0-SNAPSHOT/hello-world-bc-1.0-SNAPSHOT.xsd
[INFO] Installing /Users/bsnyder/src/hello-world-smx/hello-world-bc/target/xbean/hello-world-bc.xsd.html to
/Users/bsnyder/.m2/repository/org/apache/servicemix/samples/helloworld/bc/hello-world-bc/1.0-SNAPSHOT/hello-world-bc-1.0-SNAPSHOT-schema.html
[INFO] Installing /Users/bsnyder/src/hello-world-smx/hello-world-bc/target/hello-world-bc-1.0-SNAPSHOT-installer.zip to
/Users/bsnyder/.m2/repository/org/apache/servicemix/samples/helloworld/bc/hello-world-bc/1.0-SNAPSHOT/hello-world-bc-1.0-SNAPSHOT-installer.zip
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESSFUL
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 15 seconds
[INFO] Finished at: Tue Mar 06 19:59:50 MST 2007
[INFO] Final Memory: 13M/25M
[INFO] ------------------------------------------------------------------------
|
Notice that not only do we see that the build was successful, but also note the text in the output above that was printed by the test:
<?xml version="1.0" encoding="UTF-8"?><hello>Message [Ski Colorado!] contains [13] bytes</hello>
This is the message we were expecting to be output from the test. So if you see this, you just wrote a JBI component and tested your first JBI BC successfully.
Now let's look at how this component is deployed to ServiceMix.
Deploying the BC to ServiceMix
Thanks to Maven, this BC has already been packaged properly to be deployed to ServiceMix. Just take a look in the target directory of the project and you will see the zip file:
Panel |
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$ ls -l ./target | awk {'print $9'} classes |
This zip file contains everything needed to deploy the BC to ServiceMix. This can be done by simply copying the zip file to the ServiceMix component installation directory. By default, this is a directory named install. However, this does not complete the deployment of the BC.
In order to actually make use of the BC, you will need to create a JBI service unit (SU) that uses the BC. A SU is really just a configuration for a JBI component to tell it how to behave. Just like all the JBI components that come with ServiceMix, in order to use one, you will need to create a SU that configures it, telling the JBI container how the component should behave. But the situation with this component is a bit different. Because the Hello World BC contains a hard-coded message, there's not much configuration to be done other than just stating that it should be used. So let's create the SU for the Hello World BC and then we'll move on to testing it.
Creating a Hello World BC Service Unit
This is a work in progress Notice that not only do we see that the build was successful, but also note the text in the output above that was printed by the test (*<hello>Hello World! Message \[<hello>Ski Colorado!</hello>\] contains \[28\] bytes.</hello>*). This is the message we were expecting to be output from the test. So if you see this, you just wrote a JBI component and tested it successfully. Now this SU needs to be wrapped in a SA so it can be deployed to the JBI container. Wiki Markup
Wrapping the Service Unit in a Service Assembly
The component we created above and packaged as a SU cannot be directly deployed to a JBI container until it's wrapped in a SA. This can be done by creating a SA with a dependency on the SA. From within the hello-world-smx
directory, execute the following commands to create the project for the SA:
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$ pwd /Users/bsnyder/src/hello-world-smx/hello-world-bc-su $ cd .. $ mvn archetype:create \ -DarchetypeGroupId=org.apache.servicemix.tooling \ -DarchetypeArtifactId=servicemix-service-assembly \ -DarchetypeVersion=3.2.1-incubating-SNAPSHOT \ -DgroupId=org.apache.servicemix.samples.helloworld \ -DartifactId=hello-world-sa |
...
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[INFO] Scanning for projects... [INFO] Searching repository for plugin with prefix: 'archetype'. [INFO] ---------------------------------------------------------------------------- [INFO] Building Maven Default Project [INFO] task-segment: [archetype:create] (aggregator-style) [INFO] ---------------------------------------------------------------------------- [INFO] Setting property: classpath.resource.loader.class => 'org.codehaus.plexus.velocity.ContextClassLoaderResourceLoader'. [INFO] Setting property: velocimacro.messages.on => 'false'. [INFO] Setting property: resource.loader => 'classpath'. [INFO] Setting property: resource.manager.logwhenfound => 'false'. [INFO] ************************************************************** [INFO] Starting Jakarta Velocity v1.4 [INFO] RuntimeInstance initializing. [INFO] Default Properties File: org/apache/velocity/runtime/defaults/velocity.properties [INFO] Default ResourceManager initializing. (class org.apache.velocity.runtime.resource.ResourceManagerImpl) [INFO] Resource Loader Instantiated: org.codehaus.plexus.velocity.ContextClassLoaderResourceLoader [INFO] ClasspathResourceLoader : initialization starting. [INFO] ClasspathResourceLoader : initialization complete. [INFO] ResourceCache : initialized. (class org.apache.velocity.runtime.resource.ResourceCacheImpl) [INFO] Default ResourceManager initialization complete. [INFO] Loaded System Directive: org.apache.velocity.runtime.directive.Literal [INFO] Loaded System Directive: org.apache.velocity.runtime.directive.Macro [INFO] Loaded System Directive: org.apache.velocity.runtime.directive.Parse [INFO] Loaded System Directive: org.apache.velocity.runtime.directive.Include [INFO] Loaded System Directive: org.apache.velocity.runtime.directive.Foreach [INFO] Created: 20 parsers. [INFO] Velocimacro : initialization starting. [INFO] Velocimacro : adding VMs from VM library template : VM_global_library.vm [ERROR] ResourceManager : unable to find resource 'VM_global_library.vm' in any resource loader. [INFO] Velocimacro : error using VM library template VM_global_library.vm : org.apache.velocity.exception.ResourceNotFoundException: Unable to find resource 'VM_global_library.vm' [INFO] Velocimacro : VM library template macro registration complete. [INFO] Velocimacro : allowInline = true : VMs can be defined inline in templates [INFO] Velocimacro : allowInlineToOverride = false : VMs defined inline may NOT replace previous VM definitions [INFO] Velocimacro : allowInlineLocal = false : VMs defined inline will be global in scope if allowed. [INFO] Velocimacro : initialization complete. [INFO] Velocity successfully started. [INFO] [archetype:create] [INFO] Defaulting package to group ID: org.apache.servicemix.samples.helloworld [INFO] ---------------------------------------------------------------------------- [INFO] Using following parameters for creating Archetype: servicemix-service-assembly:3.2.1-incubating-SNAPSHOT [INFO] ---------------------------------------------------------------------------- [INFO] Parameter: groupId, Value: org.apache.servicemix.samples.helloworld [INFO] Parameter: packageName, Value: org.apache.servicemix.samples.helloworld [INFO] Parameter: basedir, Value: /Users/bsnyder/src/hello-world-smx [INFO] Parameter: package, Value: org.apache.servicemix.samples.helloworld [INFO] Parameter: version, Value: 1.0-SNAPSHOT [INFO] Parameter: artifactId, Value: hello-world-sa [WARNING] org.apache.velocity.runtime.exception.ReferenceException: reference : template = archetype-resources/pom.xml [line 71,column 18] : ${servicemix-version} is not a valid reference. [INFO] ********************* End of debug info from resources from generated POM *********************** [INFO] Archetype created in dir: /Users/bsnyder/src/hello-world-smx/hello-world-sa [INFO] ------------------------------------------------------------------------ [INFO] BUILD SUCCESSFUL [INFO] ------------------------------------------------------------------------ [INFO] Total time: 2 seconds [INFO] Finished at: Fri Jan 05 23:40:32 MST 2007 [INFO] Final Memory: 4M/8M [INFO] ------------------------------------------------------------------------ |
...
Code Block |
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$ ls
hello-world-sa hello-world-bc-su
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If you see the above directories, proceed to the next step below. If instead you see the BUILD FAILED output, you'll need to analyze the rest of the output to troubleshoot the issue. Assistance with any issue you might experience is available from the ServiceMix community via the ServiceMix mailing lists archive.
Now that we have a project for the SA, we need to edit the POM so that the project depends upon the JBI component we created above. This can be done by editing the POM for the SA to add a dependency upon the hello-world-bc-su
as listed below:
Code Block |
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<dependency> <groupId>org.apache.servicemix.samples.helloworld.bc</groupId> <artifactId>hello-world-bc-su<bc</artifactId> <version>1.0-SNAPSHOT</version> </dependency> |
...
Code Block |
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$ cd hello-world-sa $ mvn install |
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Incorporating the Projects Into a Top Level POM
Now that we have created the SU and SA projects, a top level pom.xml
must be manually created and made aware of each subproject. This will allow all the projects to be built automatically without having to build each project in order manually. Maven will discover all the projects and build them in the proper order. In the hello-world-bc-susmx
directory, create a file named pom.xml
containing the following content:
Code Block |
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<?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd"> <modelVersion>4.0.0</modelVersion> <groupId>org.apache.servicemix.samples.helloworld</groupId> <artifactId>hello-world-smx</artifactId> <packaging>pom</packaging> <version>1.0-SNAPSHOT</version> <name>Hello World JBI Component</name> <modules> <module>hello-world-sa</module> <module>hello-world-bc-su<bc</module> </modules> </project> |
...
Code Block |
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$ ls
hello-world-sa hello-world-bc-su pom.xml
|
All projects can now be built using the following command on the command-line from the top level hello-world-smx
directory:
...
As long as you see the BUILD SUCCESSFUL message in the output continue to the next section to give each project a unique name.
Give Each of the Maven Subprojects a Name
Notice in the output above that there are a two projects named A custom project. This is because the archetypes create projects with this generic name. Let's give each project a unique name via each component's pom.xml
file. This name will allow Maven's output to denote a component's name in its output making our development work a bit easier. To name each project, simply edit each pom.xml
and replace <name>A custom project</name>
with an appropriate name. Below are the instructions for naming each component's project:
- Edit
hello-world-sa/pom.xml
and replace<name>A custom project</name>
with<name>Hello World Service Assembly</name>
- Edit
hello-world-bc-su/pom.xml
and replace<name>A custom project</name>
with<name>Hello World BC Service Unit</name>
Now when the projects are built you will no longer see a project named A custom project. Instead you'll now see Hello World SE Service Unit and Hello World Service Assembly. Rebuild the projects again using the mvn clean install
command on the command-line to see the change.
Deploying the Component
Now that the SA is built, we're ready to deploy it to the JBI container.
...
Note | ||
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The default implementation of the component accepts InOut MEPs (ADD OUTLINE for further work:
Classpath for SU to include manually till v3.1, see mail manually editing http://goopen.org/confluence/display/SM/Working+with+Service+Units INS When to use this JBI Component provide exact position in the SVN! maybe moving the content of overlapping existing docus to this new tut and - where appropriate - delete the old ones (only leaving a redirect). This shall already include everything stated at provide additional reading |