The org.w3c.dom.ProcessingInstruction Interface

All Super interfaces: org.w3c.dom.Node

Members

Overview

The ProcessingInstruction interface represents a "processing instruction", used in XML as a way to keep processor-specific information in the text of the document.

Example of handling ProcessingInstructions in SAX

Processing instructions within XML are handled in a bit of special case as they are not considered XML elements. SAX defines a specific call back method for handling PIs(Processing Instructions). In a real application that is using XML data, this is where an application should receive instructions and variable values or execute methods to perform application-specific processing. E.g. the apache cocoon publishing framework might set flags to perform transformation on the data once it is parsed or to display the xml as a specific content type.

public void processingInstruction(String target, String data){

   System.out.println("PI: target: "+target+" and Date :"+data);

 }

Example of handling ProcessingInstructions in DOM

The ProcessingInstruction node in the DOM is a little bit of a break from what you have seen so far: to fit the syntax into the Node interface model, the getNodeValue() method returns all data instructions within a PI(ProcessingInstruction) in one String. This allows quick output of the PI. If you were writing an application that received PIs from an XML document, you might prefer to use the actual ProcessingInstruction interface; although it exposes the same data, the method names( getTarget() and getData()) are more in line with a PI’s format. With this understanding, you can add in the code to print out any Pis in supplied document:

            Case Node.PORCESSING_INSTRUCTION_NODE:

                        node.getNodeName();

                        node.getNodeValue();

//Perform your processing here