# The Java EE 7 Tutorial

# 34.3 A Web Service Example: helloservice

This example demonstrates a simple web service that generates a response based on information received from the client. `HelloServiceBean` is a stateless session bean that implements a single method: `sayHello`. This method matches the `sayHello` method invoked by the client described in A Simple JAX-WS Application Client.

## 34.3.1 The Web Service Endpoint Implementation Class

`HelloServiceBean` is the endpoint implementation class, typically the primary programming artifact for enterprise bean web service endpoints. The web service endpoint implementation class has the following requirements.

- The class must be annotated with either the `javax.jws.WebService` or the `javax.jws.WebServiceProvider` annotation.

- The implementing class may explicitly reference an SEI through the `endpointInterface` element of the `@WebService` annotation but is not required to do so. If no `endpointInterface` is specified in `@WebService`, an SEI is implicitly defined for the implementing class.

- The business methods of the implementing class must be public and must not be declared `static` or `final`.

- Business methods that are exposed to web service clients must be annotated with `javax.jws.WebMethod`.

- Business methods that are exposed to web service clients must have JAXB-compatible parameters and return types. See the list of JAXB default data type bindings at Types Supported by JAX-WS.

- The implementing class must not be declared `final` and must not be `abstract`.

- The implementing class must have a default public constructor.

- The endpoint class must be annotated `@Stateless`.

- The implementing class must not define the `finalize` method.

- The implementing class may use the `javax.annotation.PostConstruct` or `javax.annotation.PreDestroy` annotations on its methods for lifecycle event callbacks.

  The `@PostConstruct` method is called by the container before the implementing class begins responding to web service clients.

  The `@PreDestroy` method is called by the container before the endpoint is removed from operation.

## 34.3.2 Stateless Session Bean Implementation Class

The `HelloServiceBean` class implements the `sayHello` method, which is annotated `@WebMethod`. The source code for the `HelloServiceBean` class is as follows:

    package javaeetutorial.helloservice.ejb;

    import javax.ejb.Stateless;
    import javax.jws.WebMethod;
    import javax.jws.WebService;

    @Stateless
    @WebService
    public class HelloServiceBean {
        private final String message = "Hello, ";

        public void HelloServiceBean() {}

        @WebMethod
        public String sayHello(String name) {
            return message + name + ".";
        }
    }

## 34.3.3 Running the helloservice Example

You can use either NetBeans IDE or Maven to build, package, and deploy the `helloservice` example. You can then use the Administration Console to test the web service endpoint methods.

### 34.3.3.1 To Build, Package, and Deploy the helloservice Example Using NetBeans IDE

1. Make sure that GlassFish Server has been started (see Starting and Stopping GlassFish Server).

2. From the File menu, choose Open Project.

3. In the Open Project dialog box, navigate to:

       tut-install/examples/ejb

4. Select the `helloservice` folder.

5. Click Open Project.

6. In the Projects tab, right-click the `helloservice` project and select Build.

   This builds and packages the application into `helloservice.ear`, located in tut-install`/examples/ejb/helloservice/target/`, and deploys this EAR file to GlassFish Server.

### 34.3.3.2 To Build, Package, and Deploy the helloservice Example Using Maven

1. Make sure that GlassFish Server has been started (see Starting and Stopping GlassFish Server).

2. In a terminal window, go to:

       tut-install/examples/ejb/helloservice/

3. Enter the following command:

       mvn install

   This compiles the source files and packages the application into an EJB JAR file located at tut-install`/examples/ejb/helloservice/target/helloservice.jar`. Then the EJB JAR file is deployed to GlassFish Server.

   Upon deployment, GlassFish Server generates additional artifacts required for web service invocation, including the WSDL file.

### 34.3.3.3 To Test the Service without a Client

The GlassFish Server Administration Console allows you to test the methods of a web service endpoint. To test the `sayHello` method of `HelloServiceBean`, follow these steps.

1. Open the Administration Console by opening the following URL in a web browser:

       http://localhost:4848/

2. In the navigation tree, select the Applications node.

3. In the Applications table, click the `helloservice` link.

4. In the Modules and Components table, click the View Endpoint link.

5. On the Web Service Endpoint Information page, click the Tester link:

       /HelloServiceBeanService/HelloServiceBean?Tester

6. On the Web Service Test Links page, click the non-secure link (the one that specifies port 8080).

7. On the HelloServiceBeanService Web Service Tester page, under Methods, enter a name as the parameter to the `sayHello` method.

8. Click sayHello.

   The sayHello Method invocation page opens. Under Method returned, you'll see the response from the endpoint.