streamrepresentation.java

BEA WebLogic Server 8.1大全 = BEA webLogic server 8.1 unleashed (美) Mark Artiges等著 袁毅 ... [等] 译 eng

/* 
 * WebLogic Server Unleashed
 * 
 */
package com.wlsunleashed.xml.xpath;

import java.io.FileInputStream;
import java.io.FileNotFoundException;

import weblogic.xml.stream.Attribute;
import weblogic.xml.stream.AttributeIterator;
import weblogic.xml.stream.EndElement;
import weblogic.xml.stream.StartElement;
import weblogic.xml.stream.XMLEvent;
import weblogic.xml.stream.XMLInputStream;
import weblogic.xml.stream.XMLInputStreamFactory;
import weblogic.xml.stream.XMLStreamException;
import weblogic.xml.xpath.StreamXPath;
import weblogic.xml.xpath.XPathException;
import weblogic.xml.xpath.XPathStreamFactory;
import weblogic.xml.xpath.XPathStreamObserver;


/**
 * This class Processes a given XML using WebLogic Streaming API
 * and dumps the contents on the screen
 * 
 * @version 1.0
 */
public class StreamRepresentation {
    /** The XML file to be processed */
    private String fileName = null;

    /**
     * Creates a new StreamRepresentation object.
     *
     * @param file The XML file to be processed
     *
     */
    public StreamRepresentation(String file) {
        fileName = file;
    }

    /**
     * The entry point into this class - pass the XML file as 
     * parameter
     *
     * @param args Command line arguments
     */
    public static void main(String[] args) {
        if (args.length != 1) {
            System.out.println("Usage: StreamRepresentation <XML file>.xml");
            System.exit(1);
        }

        try {
            StreamRepresentation xmlProcessor = new StreamRepresentation(args[0]);

            xmlProcessor.process();
        } catch (Exception ex) {
            ex.printStackTrace();
        }
    }


	
    /**
     * Processes the given file
     *
     * @exceptions FileNotFoundException The file input was not found
     * @exceptions XMLStreamException Problem while parsing.
     */
    private void process()
                  throws FileNotFoundException, XMLStreamException, XPathException {
		
		StreamXPath recipientsXPath = new StreamXPath("email/to");      
		XPathStreamFactory factory = new XPathStreamFactory();
		factory.install(recipientsXPath, 
			new XPathStreamObserver() {
		      public void observe(XMLEvent event) {
		      	System.out.println("Observing Event " + event.getName());
		      	processEvent(event);
		      }
		      public void observeAttribute(StartElement e, Attribute a) {
		      	System.out.println("Observing Attribute " + a.getName() + " on element " + e.getName());
		      } 
		      public void observeNamespace(StartElement e, Attribute a) {
		      	System.out.println("Observing Namespace " + a.getName() + " on element " + e.getName());
		      } 
				
			});            	
        XMLInputStreamFactory streamFactory = XMLInputStreamFactory.newInstance();

        XMLInputStream inputStream = streamFactory.newInputStream(
                                             new FileInputStream(fileName));

		XMLInputStream searchStream = factory.createStream(inputStream);
        while (searchStream.hasNext()) {
            XMLEvent anEvent = searchStream.next();
        }
    }

    /**
     * Method processEvent.
     *
     * @param anEvent
     */
    private void processEvent(XMLEvent anEvent) {
        switch(anEvent.getType()) {
        case XMLEvent.START_ELEMENT:
            StartElement startElem = (StartElement) anEvent;
            System.out.println(" In Start Element: ");
            System.out.println("  -- name = " + startElem.getName());
            AttributeIterator attrs = startElem.getAttributes();
            while (attrs.hasNext()) {
                Attribute anAttr = attrs.next();
                System.out.println("  -- Attr name = " + anAttr.getName());
                System.out.println("  -- -- Attr value = " + anAttr.getValue());
            }
			break;
			
        case XMLEvent.END_ELEMENT:

            EndElement endElem = (EndElement) anEvent;
            System.out.println(" In End Element: ");
            System.out.println("  -- name = " + endElem.getName());
			break;
			
		default:
			System.out.println(" type = " + anEvent.getTypeAsString());
			break;
    }
    }
}