message: This section details about the message formats (or the documents)
exchanged.
portType: The PortType can be looked at as the abstract interface definition
for the exposed service.
binding: The PortType has to be mapped to specific data formats and
protocols, which will be detailed out in the binding section.
port: The port gives the URL representation of the service endpoint.
service: Service can contain a collection of port elements.
Since JBI is based on WSDL, we will deal with many WSDL instances in the
subsequent chapters.
SOAP
In web services, data is transmitted over the wire in SOAP. SOAP is an XML-based
messaging protocol. SOAP defines a set of rules for structuring messages that can
be used for simple one-way messaging and is useful for performing RPC-style
interactions. Even though SOAP is not tied to any particular transport protocol,
HTTP is the popular one.
A SOAP-encoded RPC dialogue contains both a request message and a response
message. Let us consider a simple service method that takes a String parameter and
returns a String type:
public String hello(String param);
??? ??? ??? ??? ??? ???
Chapter 2
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The respective SOAP request is shown as follows:
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