SAAJ stands for SOAP with Attachments API for Java - contains APIs for creating and populating SOAP messages, which may or may not contain attachments. It also contains APIs for sending point-to-point, non-provider-based, request and response SOAP messages.
SOAP message is made of SOAP Envelope with zero or more attachments. The SOAP Envelope is then made of SOAP Header and SOAP Body. SOAP attachment allows the SOAP message to contain not only the XML data but also non-XML data such as JPG file. Each attachment is defined by a MIME type and can assume any content represented as a byte stream. SOAP's attachment feature is vary useful when a client wants to transmit binary data, such as an image or audio data, to a Web service.
SAAJ provides a convenient library to construct and
read SOAP messages, and also lets you send and receive SOAP messages across the
network. SAAJ defines the namespace
The process involves five steps:
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