Using JAX-WS and AWS Elastic Beanstalk to Design, Develop and Deploy Java Web Services
Web services are technology neutral web based components or applications that use XML-based open standards to enable interoperability in integration. Java introduced Java API for XML Web Services (JAX-WS) for creating web services. JAX-WS API is part of the Java EE platform and supports annotations. It simplifies the development of web service providers and web service clients.
Our goal is to locally design, develop and test a web service and finally deploy it to the AWS Elastic Beanstalk. We will develop a simple web service with top-down approach meaning we will design our web service interface first and then implement it using JAX-WS. To generate Java classes from XML schemas and WSDL, we will use Apache CXF framework. We will also follow best practices while designing and developing our web service.
Let’s design generic XML schemas and a simple, generic, WS-I compliant WSDL. A good practice is to design business objects and messages that envelope business object in web service operations, separately and in different namespaces.
First, we create a library project (general project in Eclipse IDE) and design two business schemas and three messages for our operation:
Now, we can design a web service interface (WSDL) with a single “doSomething” operation with an input, output and business fault. Best practice is to use envelope messages for input, output and fault. In our case we use three messages – request, response and fault message defined above.
To ensure true interoperability and be compliant with WS-I we should follow best practices and use document/literal SOAP binding. You can read about WSDL styles here.
Now we can start with top-down development of our web service. To enable this, we must configure our environment. We use:
In Eclipse we generate a new Dynamic Web Project with configured Apache CXF and Tomcat 7.0 runtime (make sure your web service runtime is also set to Tomcat 7.0 and Apache CXF). Note we use jdk 1.6.
We add a new top-down web service, select our WSDL from the library project and let Apache CXF and wsdl2java to generate JAX-WS stubs and JAXB Java classes we can use in the implementation.
If we take a look at the generated classes we can see they are annotated with JAXB and JAX-WS annotations. We can implement our service in the MyServiceImpl.java class. In the interface we can cleary see the JAX-WS annotations.
The service endpoint is defined in the copied WSDL in the WebContent/wsdl foler. In our case the service looks like this:
To test it we deploy it locally on the Tomcat 7.0 server and use SoapUI to test it.
Now we are ready to deploy our web service on the AWS Elastic Beanstalk that automatically handles the deployment, capacity provisioning, load balancing, auto-scaling and application health monitoring. It supports Apache Tomcat 6 and 7, Microsoft IIS 7.5 and 8, PHP 5.3, Phyton, Ruby 1.8.7 and 1.9.3.
To deploy our application on the AWS Elastic Beanstalk from Eclipse we need the AWS Toolkit for Eclipse. When we configure our AWS credentials (access key ID and secret key are accessible in the AWS portal) in the AWS toolkit, we add a new Server > Amazon Web Services > AWS Elastic Beanstalk for Tomcat 7.0. We choose the region (in our case – Ireland) and configure our application and environment.
Next, we can deploy the application with specific key pair, enable SSL, assign CNAME to the server, set the application health check URL and assign the email address for notifications. In our case, we will leave all fields empty. Then we add the project on the server, start it and wait (in our case it took about 8 minutes).
After the deployment we can take a look at our AWS Managemen Conolse > Elastic Beanstalk. Here we can manage our AWS Elastic Beanstalk applications.
Our application is hosted in the AWS S3 bucket in the same region as the AWS Elastic Beanstalk application.
WSDL of our web service is located on:
Finally, we can test the web service, running on AWS Elastic Beanstalk using SoapUI.
You can download the sample here.