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Developing Client Applications to Use a Web Service

(The WSDL Basic Profile 1.0 does not support 

javax.xml.transform.Source

objects as mime types. As a result, you should avoid this usage until it is sup 

ported by a future WSDL version.) A service may also return complex types, and

these are mapped to Java 

Object

 representations. For more information, see

 Parameter Types for Web Service Operations  on page 72. 

When stubs are used, the JAX RPC WSDL to Java mapping tool maps

parameter, exception, and return value types into the generated classes using

information contained in the developer provided WSDL document. Complex

types defined within a WSDL document are represented by individual Java classes,

as are faults. A WSDL to Java mapping tool included with the JAX RPC runtime

also generates classes to serialize and deserialize these values to XML. The JAX 

RPC runtime uses these generated classes to serialize parameter values into a

SOAP message and deserialize return values and exceptions.

E

Use WSDL to Java tools to generate support classes, even if using the dynamic 

proxy or DII approach.

Whenever possible, developers should try to use a tool to do the WSDL to 

Java mapping, since a tool correctly handles the WSDL format and mapping

semantics. Note that the Java objects generated by these mapping tools contain

empty constructors and get and set methods for elements. You should use the

empty constructor to create an instance of the object and set any field or element

values using the corresponding set methods. JAX RPC does not guarantee that it

will correctly map values created as part of the constructor to the corresponding

fields. 

Although not advisable, it is possible for a developer to work without the

benefit of a mapping tool, if none are available. However, without such mapping

tools the scope of the developer's work greatly expands. For example, just to

compile the client code, the developer must understand the WSDL for a service

and generate by hand Java classes that match the parameter and return types

defined in the WSDL document or, in the case of a dynamic proxy, the client side

representation of the service endpoint interface. These classes must be set up prop 

erly so that the JAX RPC runtime can match SOAP message types to the corre 

sponding Java objects.