INTERACTIVE WEB SERVICES WITH JAVA

Using SOAP

Using SOAP typically means:

when sending messages, put them into a SOAP envelope
when receiving messages, take them out of the SOAP envelope

An envelope is a wrapper containing:

a header - information to intermediaries (network nodes on the message path)
a body - the actual contents (depending on the application)

Example document-style SOAP message (from the SOAP primer):

<?xml version='1.0' ?> <env:Envelope xmlns:env="http://www.w3.org/2002/06/soap-envelope"> <env:Header> <m:reservation xmlns:m="http://travelcompany.example.org/reservation" env:role="http://www.w3.org/2002/06/soap-envelope/role/next" env:mustUnderstand="true"> <m:reference>uuid:093a2da1-q345-739r-ba5d-pqff98fe8j7d</m:reference> <m:dateAndTime>2001-11-29T13:20:00.000-05:00</m:dateAndTime> </m:reservation> <n:passenger xmlns:n="http://mycompany.example.com/employees" env:role="http://www.w3.org/2002/06/soap-envelope/role/next" env:mustUnderstand="true"> <n:name>John Q. Public</n:name> </n:passenger> </env:Header> <env:Body> <p:itinerary xmlns:p="http://travelcompany.example.org/reservation/travel"> <p:departure> <p:departing>New York</p:departing> <p:arriving>Los Angeles</p:arriving> <p:departureDate>2001-12-14</p:departureDate> <p:departureTime>late afternoon</p:departureTime> <p:seatPreference>aisle</p:seatPreference> </p:departure> <p:return> <p:departing>Los Angeles</p:departing> <p:arriving>New York</p:arriving> <p:departureDate>2001-12-20</p:departureDate> <p:departureTime>mid-morning</p:departureTime> <p:seatPreference/> </p:return> </p:itinerary> <q:lodging xmlns:q="http://travelcompany.example.org/reservation/hotels"> <q:preference>none</q:preference> </q:lodging> </env:Body> </env:Envelope>

<?xml version='1.0' ?> <env:Envelope xmlns:env="http://www.w3.org/2002/06/soap-envelope"> <env:Header> <m:reservation xmlns:m="http://travelcompany.example.org/reservation" env:role="http://www.w3.org/2002/06/soap-envelope/role/next" env:mustUnderstand="true"> <m:reference>uuid:093a2da1-q345-739r-ba5d-pqff98fe8j7d</m:reference> <m:dateAndTime>2001-11-29T13:20:00.000-05:00</m:dateAndTime> </m:reservation> <n:passenger xmlns:n="http://mycompany.example.com/employees" env:role="http://www.w3.org/2002/06/soap-envelope/role/next" env:mustUnderstand="true"> <n:name>John Q. Public</n:name> </n:passenger> </env:Header> <env:Body> <p:itinerary xmlns:p="http://travelcompany.example.org/reservation/travel"> <p:departure> <p:departing>New York</p:departing> <p:arriving>Los Angeles</p:arriving> <p:departureDate>2001-12-14</p:departureDate> <p:departureTime>late afternoon</p:departureTime> <p:seatPreference>aisle</p:seatPreference> </p:departure> <p:return> <p:departing>Los Angeles</p:departing> <p:arriving>New York</p:arriving> <p:departureDate>2001-12-20</p:departureDate> <p:departureTime>mid-morning</p:departureTime> <p:seatPreference/> </p:return> </p:itinerary> <q:lodging xmlns:q="http://travelcompany.example.org/reservation/hotels"> <q:preference>none</q:preference> </q:lodging> </env:Body> </env:Envelope>

boldface parts are SOAP data, the rest is application-specific
the next role means that the header blocks are targeted at the next SOAP node encountered en route
mustUnderstand="true" means that the header blocks cannot be ignored

The big question: What value does SOAP add?