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package demo.hw.server;

import org.apache.hello_world_soap_http.Greeter;

@javax.jws.WebService(portName = "SoapPort", serviceName = "SOAPService",
 targetNamespace = "http://apache.org/hello_world_soap_http",
 endpointInterface = "org.apache.hello_world_soap_http.Greeter")

public class GreeterImpl implements Greeter {

 public String greetMe(String me)
{
        System.out.println("Executing operation greetMe");
        System.out.println("Message received: " + me + "\n");
        return "Hello " + me;
     }

 public String sayHi()
{
        System.out.println("Executing operation sayHi\n");
        return "Bonjour";
     }
}

Java First Development

To create a service starting from Java you need to do the following:

1. Create a Service Endpoint Interface (SEI) that defines the methods you wish to expose as a service.

   Tip
   tile Tip
   You can work directly from a Java class, but working from an interface is the recommended approach. Interfaces are better for sharing with the developers who will be responsible for developing the applications consuming your service. The interface is smaller and does not provide any of the service's implementation details.

2. Add the required annotations to your code.
3. Generate the WSDL contract for your service.

   Tip
   title Tip
   If you intend to use the SEI as the service's contract, it is not necessary to generate a WSDL contract

4. Publish the service.

Creating the SEI

The service endpoint interface (SEI) is the piece of Java code that is shared between a service and the consumers that make requests on it. When starting with a WSDL contract, the SEI is generated by the code generators. However, when starting from Java, it is the up to a developer to create the SEI.

There are two basic patterns for creating an SEI:

• Green field development
  You are developing a new service from the ground up. When starting fresh, it is best to start by creating the SEI first. You can then distribute the SEI to any developers that are responsible for implementing the services and consumers that use the SEI.

  Note
  title Note
  The recommended way to do green field service development is to start by creating a WSDL contract that defines the service and its interfaces.

• Service enablement
  In this pattern, you typically have an existing set of functionality that is implemented as a Java class and you want to service enable it. This means that you will need to do two things:
  1. Create an SEI that contains only the operations that are going to be exposed as part of the service.
  2. Modify the existing Java class so that it implements the SEI.

     Note
     title Note
     You can add the JAX-WS annotations to a Java class, but that is not recommended.

Writing the interface

The SEI is a standard Java interface. It defines a set of methods that a class will implement. It can also define a number of member fields and constants to which the implementing class has access.

In the case of an SEI the methods defined are intended to be mapped to operations exposed by a service. The SEI corresponds to a wsdl:portType element. The methods defined by the SEI correspond to wsdl:operation elements in the wsdl:portType element.

#Example2 shows a simple SEI for a stock updating service.

package org.apache.cxf;

public interface quoteReporter
{
  public Quote getQuote(String ticker);
}

Implementing the interface

Because the SEI is a standard Java interface, the class that implements it is just a standard Java class. If you started with a Java class you will need to modify it to implement the interface. If you are starting fresh, the implementation class will need to implement the SEI.

#Example3 shows a class for implementing the interface in #Example2.

package org.apache.cxf;

import java.util.*;

public class stockQuoteReporter implements quoteReporter
{
  ...
public Quote getQuote(String ticker)
  {
    Quote retVal = new Quote();
    retVal.setID(ticker);
    retVal.setVal(Board.check(ticker));[1]
    Date retDate = new Date();
    retVal.setTime(retDate.toString());
    return(retVal);
  }
}

Annotating the Code

JAX-WS relies on the annotation feature of Java 5. The JAX-WS annotations are used to specify the metadata used to map the SEI to a fully specified service definition. Among the information provided in the annotations are the following:

• The target namespace for the service.
• The name of the class used to hold the request message.
• The name of the class used to hold the response message.
• If an operation is a one way operation.
• The binding style the service uses.
• The name of the class used for any custom exceptions.
• The namespaces under which the types used by the service are defined.

  Tip
  title Tip
  Most of the annotations have sensible defaults and do not need to be specified. However, the more information you provide in the annotations, the better defined your service definition. A solid service definition increases the likely hood that all parts of a distributed application will work together.

Required Annotations

In order to create a service from Java code you are only required to add one annotation to your code. You must add the @WebService() annotation on both the SEI and the implementation class.

The @WebService annotation

The @WebService annotation is defined by the javax.jws.WebService interface and it is placed on an interface or a class that is intended to be used as a service. @WebService has the following properties:

Annotating the SEI

The SEI requires that you add the @WebService annotation. Since the SEI is the contract that defines the service, you should specify as much detail as you can about the service in the @WebService annotation's properties.

#Example4 shows the interface defined in #Example2 with the @WebService annotation.

package com.iona.demo;

import javax.jws.*;

@WebService(name="quoteUpdater",
            targetNamespace="http:\\cxf.apache.org",
	    serviceName="updateQuoteService",
            wsdlLocation="http:\\cxf.apache.org\quoteExampleService?wsdl",
            portName="updateQuotePort")
public interface quoteReporter
{
  public Quote getQuote(String ticker);
}

The @WebService annotation in #Example4 does the following:

1. Specifies that the value of the name attribute of the wsdl:portType element defining the service interface is quoteUpdater.
2. Specifies that the target namespace of the service is http:
cxf.apache.org.
3. Specifies that the value of the name of the wsdl:service element defining the published service is updateQuoteService.
4. Specifies that the service will publish its WSDL contract at http:\\cxf.apache.org\quoteExampleService?wsdl.
5. Specifies that the value of the name attribute of the wsdl:port element defining the endpoint exposing the service is updateQuotePort.

Annotating the service implementation

In addition to annotating the SEI with the @WebService annotation, you also have to annotate the service implementation class with the @WebService annotation. When adding the annotation to the service implementation class you only need to specify the endpointInterface property. As shown in #Example5 the property needs to be set to the full name of the SEI.

package org.apache.cxf;

import javax.jws.*;

@WebService(endpointInterface="org.apache.cxf.quoteReporter")
public class stockQuoteReporter implements quoteReporter
{
public Quote getQuote(String ticker)
  {
  ...
  }
}

Optional Annotations

While the @WebService annotation is sufficient for service enabling a Java interface or a Java class, it does not provide a lot of information about how the service will be exposed as an endpoint. The JAX-WS programming model uses a number of optional annotations for adding details about your service, such as the binding it uses, to the Java code. You add these annotations to the service's SEI.

Defining the Binding Properties with Annotations

If you are using a SOAP binding for your service, you can use JAX-WS annotations to specify a number of the bindings properties. These properties correspond directly to the properties you can specify in a service's WSDL contract.

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The @SOAPBinding annotation

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The @SOAPBinding annotation is defined by the javax.jws.soap.SOAPBinding interface. It provides details about the SOAP binding used by the service when it is deployed. If the @SOAPBinding annotation is not specified, a service is published using a wrapped doc/literal SOAP binding.

You can put the @SOAPBinding annotation on the SEI and any of the SEI's methods. When it is used on a method, setting of the method's @SOAPBinding annotation take precedent.

The following table shows the properties for the @SOAPBinding annotation.

#Example6 shows an SEI that uses rpc/literal SOAP messages.

package org.eric.demo;

import javax.jws.*;
import javax.jws.soap.*;
import javax.jws.soap.SOAPBinding.*;

@WebService(name="quoteReporter")
@SOAPBinding(style=Style.RPC, use=Use.LITERAL)
public interface quoteReporter
{
  ...
}

Defining Operation Properties with Annotations

When the runtime maps your Java method definitions into XML operation definitions it fills in details such as:

• what the exchanged messages look like in XML.
• if the message can be optimized as a one way message.
• the namespaces where the messages are defined.

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The @WebMethod annotation

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The @WebMethod annotation is defined by the javax.jws.WebMethod interface. It is placed on the methods in the SEI. The @WebMethod annotation provides the information that is normally represented in the wsdl:operation element describing the operation to which the method is associated.

The following table describes the properties of the @WebMethod annotation.

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The @RequestWrapper annotation

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The @RequestWrapper annotation is defined by the javax.xml.ws.RequestWrapper interface. It is placed on the methods in the SEI. As the name implies, @RequestWrapper specifies the Java class that implements the wrapper bean for the method parameters that are included in the request message sent in a remote invocation. It is also used to specify the element names, and namespaces, used by the runtime when marshalling and unmarshalling the request messages.

The following table describes the properties of the @RequestWrapper annotation.

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The @ResponseWrapper annotation

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The @ResponseWrapper annotation is defined by the javax.xml.ws.ResponseWrapper interface. It is placed on the methods in the SEI. As the name implies, @ResponseWrapper specifies the Java class that implements the wrapper bean for the method parameters that are included in the response message sent in a remote invocation. It is also used to specify the element names, and namespaces, used by the runtime when marshalling and unmarshalling the response messages.

The following table describes the properties of the @ResponseWrapper annotation.

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The @WebFault annotation

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The @WebFault annotation is defined by the javax.xml.ws.WebFault interface. It is placed on methods in the SEI that throw exceptions. The @WebFault annotation is used to map the Java exception to a wsdl:fault element. This information is used to marshall the exceptions into a representation that can be processed by both the service and its consumers.

The following table describes the properties of the @WebFault annotation.

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The @OneWay annotation

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The @OneWay annotation is defined by the javax.jws.OneWay interface. It is placed on the methods in the SEI that will not require a response from the service. The @OneWay annotation tells the run time that it can optimize the execution of the method by not waiting for a response and not reserving any resources to process a response.

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Example

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#Example7 shows an SEI whose methods are annotated.

package org.apache.cxf;

import javax.jws.*;
import javax.xml.ws.*;

@WebService(name="quoteReporter")
public interface quoteReporter
{
  @WebMethod(operationName="getStockQuote")
  @RequestWrapper(targetNamespace="http://demo.iona.com/types",
                  className="java.lang.String")
  @ResponseWrapper(targetNamespace="http://demo.iona.com/types",
                   className="org.eric.demo.Quote")
  public Quote getQuote(String ticker);
}

Defining Parameter Properties with Annotations

The method parameters in the SEI coresspond to the wsdl:message elements and their wsdl:part elements. JAX-WS provides annotations that allow you to describe the wsdl:part elements that are generated for the method parameters.

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The @WebParam annotation

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The @WebParam annotation is defined by the javax.jws.WebParam interface. It is placed on the parameters on the methods defined in the SEI. The @WebParam annotation allows you to specify the direction of the parameter, if the parameter will be placed in the SOAP header, and other properties of the generated wsdl:part.

The following table describes the properties of the @WebParam annotation.

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The @WebResult annotation

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The @WebResult annotation is defined by the javax.jws.WebResult interface. It is placed on the methods defined in the SEI. The @WebResult annotation allows you to specify the properties of the generated wsdl:part that is generated for the method's return value.

The following table describes the properties of the @WebResult annotation.

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Example

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#Example8 shows an SEI that is fully annotated.

package org.apache.cxf;

import javax.jws.*;
import javax.xml.ws.*;
import javax.jws.soap.*;
import javax.jws.soap.SOAPBinding.*;
import javax.jws.WebParam.*;

@WebService(name="quoteReporter")
@SOAPBinding(style=Style.RPC, use=Use.LITERAL)
public interface quoteReporter
{
  @WebMethod(operationName="getStockQuote")
  @RequestWrapper(targetNamespace="http://demo.iona.com/types",
                  className="java.lang.String")
  @ResponseWrapper(targetNamespace="http://demo.iona.com/types",
                   className="org.eric.demo.Quote")
  @WebResult(targetNamespace="http://demo.iona.com/types",
             name="updatedQuote")
  public Quote getQuote(
                        @WebParam(targetNamespace="http://demo.iona.com/types",
                                  name="stockTicker",
                                  mode=Mode.IN)
                        String ticker
  );
}

Generating WSDL

Once you have annotated your code, you can generate a WSDL contract for your service using the java2wsdl command.

Example

#Example9 shows the WSDL contract generated for the SEI shown in #Example8.

<?xml version="1.0" encoding="UTF-8"?>
<wsdl:definitions targetNamespace="http://demo.eric.org/"
                  xmlns:tns="http://demo.eric.org/"
		  xmlns:ns1=""
		  xmlns:xsd="http://www.w3.org/2001/XMLSchema"
		  xmlns:ns2="http://demo.eric.org/types"
		  xmlns:soap="http://schemas.xmlsoap.org/wsdl/soap/"
		  xmlns:wsdl="http://schemas.xmlsoap.org/wsdl/">
  <wsdl:types>
    <xsd:schema>
      <xs:complexType name="quote">
        <xs:sequence>
          <xs:element name="ID" type="xs:string" minOccurs="0"/>
          <xs:element name="time" type="xs:string" minOccurs="0"/>
          <xs:element name="val" type="xs:float"/>
        </xs:sequence>
      </xs:complexType>
    </xsd:schema>
  </wsdl:types>
  <wsdl:message name="getStockQuote">
    <wsdl:part name="stockTicker" type="xsd:string">
    </wsdl:part>
  </wsdl:message>
  <wsdl:message name="getStockQuoteResponse">
    <wsdl:part name="updatedQuote" type="tns:quote">
    </wsdl:part>
  </wsdl:message>
  <wsdl:portType name="quoteReporter">
    <wsdl:operation name="getStockQuote">
      <wsdl:input name="getQuote" message="tns:getStockQuote">
    </wsdl:input>
      <wsdl:output name="getQuoteResponse" message="tns:getStockQuoteResponse">
    </wsdl:output>
    </wsdl:operation>
  </wsdl:portType>
  <wsdl:binding name="quoteReporterBinding" type="tns:quoteReporter">
    <soap:binding style="rpc" transport="http://schemas.xmlsoap.org/soap/http"/>
    <wsdl:operation name="getStockQuote">
      <soap:operation style="rpc"/>
      <wsdl:input name="getQuote">
        <soap:body use="literal"/>
      </wsdl:input>
      <wsdl:output name="getQuoteResponse">
        <soap:body use="literal"/>
      </wsdl:output>
    </wsdl:operation>
  </wsdl:binding>
  <wsdl:service name="quoteReporterService">
    <wsdl:port name="quoteReporterPort" binding="tns:quoteReporterBinding">
      <soap:address location="http://localhost:9000/quoteReporterService"/>
    </wsdl:port>
  </wsdl:service>
</wsdl:definitions>