how to use web service API?

Our application is written in Java. Now we are integrating with a different company which offers web service API. This API allows Microsoft.NET or SOAP enabled application to integrate. Please consider me in 开发者_运维知识库this naive. So how do I verify if my application is SOAP enabled or how do I make it? Actually our current plan to integrate is through data transfer between two systems. But some customers want single sign on. So I am thinking of using their API in our application.

There are many web service libraries available for Java. One is included by default in Java 6, and is available for Java 5 here https://metro.dev.java.net/