Class DocFlavor

DocFlavor provides a description of the format in which the print data will be supplied in a print job to the print service.

A doc flavor consists of two parts:

• The MIME type (Multipurpose Internet Mail Extensions types as described in RFC 2045/2046) specifying the media format of the print data.
• The representation class name which is the fully qualified name of the class providing the print data to the print job. For example if the print data is supplied as a byte array the representation class name will be "[B" or for an input stream "java.io.InputStream".

The DocFlavor class is therefore used in several places in the Java Print Service API. A print service provides its supported document flavors as an array of DocFlavor objects and a print job gets the flavor of its data to print from the Doc object provided as a DocFlavor instance.

It has to be differentiated between client formatted and service formatted print data. Client formatted print data is already provided formatted by the client e.g. in an image format or as postscript. For service formatted print data, the Java Print Service instance produces the formatted print data. Here the doc flavor's representation class name does specify an interface instead of the actual print data source. The print service will call the methods of the given implementation of this interface with a special Graphics object capable of producing formatted print data from the graphics routines inside the interface methods.

Client formatted print data document flavors

The print service uses the representation class of the doc flavor to know how to retrieve the print data. If the representation class is a URL it will open the URL to read the print data from it. If it is a byte[] it will directly use the array and send it to the printer. There are predefined doc flavor as inner class for the most common representation class types:

• Character arrays (char[]): The characters of the array represent the print data.
• Character streams (java.io.Reader): The whole characters read from the stream represent the print data.
• String (java.lang.String): The characters of the String represent the print data.
• Byte arrays (byte[]): The bytes of the array represent the print data. Encoding if text content is given in the mime type.
• Byte streams (java.io.InputStream): The whole bytes read from the stream represent the print data. If text content the encoding is specified in the mime type.
• Uniform Resource Locator (java.net.URL): The bytes read from the stream through opening of the URL represent the print data. If text content the encoding is specified in the mime type.

Service formatted print data document flavors

The print service uses the provided object implementing the interface specified by the representation class to produce the formatted print data. The mime type of service formatted data is always "application/x-java-jvm-local-objectref" to signal the local reference to the print data object implementing the interface. Predefined doc flavor classes exist as an inner class for the three available interface to produce print data:

• Pageable object (java.awt.print.Pageable): A pageable object is supplied to the print service. The print service will call the methods of the interface with a Grahics object to produce the formatted print data.
• Printable object (java.awt.print.Printable): A printable object is supplied to the print service. The print service will call the methods of the interface with a Grahics object to produce the formatted print data.
• Renderable Image object (java.awt.image.renderable.RenderableImage): A renderable image object is supplied to the print service. The print service calls methods of this interface to obtain the image to be printed.