Send and receive SOAP messages with SAAJ

In this tip, author and developer Nicholas Chase shows you how to use the SOAP with Attachments API for Java (SAAJ) to simplify the process of creating and sending SOAP messages.

The foundation of Web services lies in the sending and receiving of messages in a standard format so that all systems can understand them. Typically, that format is SOAP. A SOAP message can be generated and sent manually, but the SOAP with Attachments API for Java (SAAJ) -- an offshoot of the Java API for XML Messaging (JAXM) -- automates many of the required steps, such as creating connections or creating and sending the actual messages. This tip chronicles the creation and sending of a synchronous SOAP message.

The process involves five steps:

1. Creating a SOAP connection
2. Creating a SOAP message
3. Populating the message
4. Sending the message
5. Retrieving the reply

SAAJ is available as part of the Java Web Services Developer Pack 1.2 (see Resources). This package also includes a copy of the Tomcat Web server (so you can host your own service) and sample applications.