You can migrate web services that were developed using
Apache SOAP to Java™ API for XML-based RPC (JAX-RPC)
web services that are developed based on the Web Services for Java Platform, Enterprise Edition (Java EE) specification.
Before you begin
If you have used web services based on Apache SOAP and
now want to develop and implement web services that are Java-based,
you need to migrate client applications developed with all versions
of 4.0, and versions of 5.0 prior to 5.0.2.
About this task
SOAP-Security (XML digital signature) based on Apache
SOAP implementation has been removed. Instead of using SOAP-Security,
migrate and re-configure your application to the JSR-109 implementation
of web services.
To migrate these client applications
according to Java standards:
Procedure
- Plan your migration strategy.
You can port an
Apache SOAP client to a JAX-RPC web services client in one of two
ways:
Because JAX-RPC does not specify a framework for user-written
serializers, the JAX-RPC does not support the use of custom serializers.
If your application cannot conform to the default mapping between Java, WSDL, and XML technology supported by WebSphere® Application Server, do not attempt
to migrate the application.
The remainder of this topic
assumes that you decided to use the JAX-RPC dynamic invocation interface
(DII) APIs.
- Review the GetQuote Sample.
A web services migration Sample is available in
the Samples documentation. This sample is located in the GetQuote.java file,
originally written for Apache SOAP users, and includes an explanation about the changes needed to
migrate to the JAX-RPC DII interfaces. To learn more, see the Samples documentation.
- Convert the client application from Apache SOAP to JAX-RPC
DII
The Apache SOAP API and JAX-RPC DII API structures
are similar. You can instantiate and configure a call object, set
up the parameters, invoke the operation, and process the result in
both.
You can create a generic instance of a Service object with the following
command:
javax.xml.rpc.Service service = ServiceFactory.newInstance().createService(new QName(""));
in JAX-RPC.
- Create the Call object.
An instance of the Call object is created with the following
code:
org.apache.soap.rpc.Call call = new org.apache.soap.rpc.Call ()
in
Apache SOAP.
An instance of the Call object is created by
java.xml.rpc.Call call = service.createCall();
in JAX-RPC.
- Set the endpoint Uniform Resource Identifiers (URI).
The target URI for the operation is passed as a parameter to
call.invoke: call.invoke("http://...", "");
in Apache SOAP.
The
setTargetEndpointAddress method is used as a parameter to
call.setTargetEndpointAddress("http://...");
in JAX-RPC.
Apache SOAP has
a setTargetObjectURI method on the Call object that contains routing information for the request.
JAX-RPC has no equivalent method. The information in the targetObjectURI is included in the
targetEndpoint URI for JAX-RPC.
- Set the operation name.
The operation name is configured on the Call object by
call.setMethodName("opName");
in Apache SOAP.
The setOperationName method,
which accepts a
QName instead of a
String parameter,
is used in JAX-RPC as illustrated in the following
example:
call.setOperationName(new javax.xml.namespace.Qname("namespace", "opName"));
- Set the encoding style.
The encoding style is configured on the Call object by
call.setEncodingStyleURI(org.apache.soap.Constants.NS_URI_SOAP_ENC);
in
Apache SOAP.
The encoding style is set by a property of the Call object
call.setProperty(javax.xml.rpc.Call.ENCODINGSTYLE_URI_PROPERTY, "http://schemas.
xmlsoap.org/soap/encoding/");
in
JAX-RPC.
- Declare the parameters and set the parameter values.
Apache SOAP parameter types and values are described by parameter instances, which are
collected into a vector and set on the Call object before the call, for example:
Vector params = new Vector ();
params.addElement (new org.apache.soap.rpc.Parameter(name, type, value, encodingURI));
// repeat for additional parameters...
call.setParams (params);
For
JAX-RPC, the Call object is configured with parameter names and types without providing their
values, for example:
call.addParameter(name, xmlType, mode);
// repeat for additional parameters
call.setReturnType(type);
Where
- name (type
java.lang.String
) is the name of the
parameter
- xmlType (type
javax.xml.namespace.QName
) is the XML type of
the parameter
- mode (type
javax.xml.rpc.ParameterMode
) the mode of the
parameter, for example, IN, OUT, or INOUT
- Make the call.
The operation is invoked on the Call object by
org.apache.soap.Response resp = call.invoke(endpointURI, "");
in Apache
SOAP.
The parameter values are collected into an array and passed to
call.invoke
as illustrated in the following example:
Object resp = call.invoke(new Object[] {parm1, parm2,...});
in
JAX-RPC.
- Check for faults.
You can check for a SOAP fault on the invocation by checking the response:
if resp.generatedFault then {
org.apache.soap.Fault f = resp.getFault;
f.getFaultCode();
f.getFaultString();
}
in
Apache SOAP.
A
java.rmi.RemoteException
error is displayed in JAX-RPC if a SOAP
fault occurs on the invocation.
try {
... call.invoke(...)
} catch (java.rmi.RemoteException) ...
- Retrieve the result.
In Apache SOAP, if the invocation is successful and returns a result, it can be retrieved from
the Response object:
Parameter result = resp.getReturnValue(); return result.getValue();
In
JAX-RPC, the result of invoke is the returned object when no exception is displayed:
Object result = call.invoke(...);
...
return result;
Results
You have migrated Apache SOAP web services to a JAX-RPC Web
services based on the Java EE specification.
What to do next
Develop a web services client based on the Web Services for Java EE specification.
Test the web services-enabled clients to
make sure that the migration process is successful and you can implement
the web services in a Java EE environment.