JAXB, Web Services, and Binary Data

When an instance of a class is used with a Web Service, the JAX-WS implementation can choose to handle fields/properties that hold binary data as SOAP attachment.  An attachment is a means to send the data outside of the XML message, this is done as an optimization since binary data encoded as a xs:base64Binary string could be quite large.  JAXB offers a couple of annotations to control this behaviour:

• @XmlInlineBinaryData
  This specifies that the binary data for this field/property must be written to the XML document as xs:base64Binary and not sent as an attachment.
  
• @XmlMimeType
  For properties of type java.awt.Image or javax.xml.transform.Source, this annotation allows the mime type to be specified that will be used for encoding the data as bytes.