What is the difference between a Top-Down and Bottom-Up approach in SOAP Web Services?

Top Down approach in SOAP-

1. Top Down approach involves creating a WSDL and then creating the Web service using the WSDL file.
2. In top-down approach, first you design the implementation of the Web service by creating a WSDL file. You can then create the Web service skeleton Java classes from the wsdl, and add the required code.

Bottom Up approach in SOAP-

1. When creating a web service using Bottom Up approach, first you write the java classes for the web service and then create the WSDL file and publish the web service.
2. Although bottom-up Web service development may be faster and easier, the top-down approach is the recommended way of creating a Web service.

Hi,

To make it more simple-

Top-down means you start with a WSDL and then create all the necessary scaffolding  all the way down.

Bottom-up means you start with a your method, and generate the WSDL from it.

Hope this helps.