Chiew,
To actually manipulate your complex objects you would need to add code to your java service to traverse your object hierarchy and construct an IData (document) that your service would put onto the pipeline. Then your Flow services could manipulate this data or transform it into other formats.
One technique that I have used in the past is to build methods that walk one of the objects (say a java List of customer objects) and convert that object into an Idata (document).
I put these helper services into “Source” area of the “Shared” tab in the java service editor. In the main part of the java service I use these helper services to process each part of the complex object and then assemble the resulting document or document lists into a single Idata document that can be returned for further processing.
In the past I tried to construct the IData to match the structure that I eventually wanted to return to my trading partner, but I think an easier approach it to make your document structure resemble the java object hierarchy and then perform any additional structural transformation using Flow. I guess the correct approach depends on how much java code you want to write to produce the document.
The WmSamples package contains some useful examples for walking and creating IData documents.
Mark
#Integration-Server-and-ESB#webMethods#Adapters-and-E-Standards