使用DOMParser 解析xml的Java代码

import java.io.*;
import java.net.*;
import org.w3c.dom.*;
import org.w3c.dom.Node.*;

import oracle.xml.parser.v2.*;

/**
 * -----------------------------------------------------------------------------
 * Demonstrate how to use DOM.
 *
 * @version 1.0
 * @author  Jeffrey M. Hunter  ([email?protected])
 * @author  http://www.idevelopment.info
 * -----------------------------------------------------------------------------
 */

public class DOMExample {

    /*
     * +---------------------------------------------+
     * | METHOD: main                                |
     * +---------------------------------------------+
     */
    static public void main(String[] argv) {
        try {

            if (argv.length != 1) {
                // must pass in the name of the XML file
                System.err.println("Usage: java DOMExample filename");
                System.exit(1);
            }

            // Get an instance of the parser
            DOMParser parser = new DOMParser();

            // Generate a URL from the filename
            URL url = createURL(argv[0]);

            // Set various parser options; validation on,// warnings shown,error stream set to stderr.
            parser.setErrorStream(System.err);
            parser.setValidationMode(true);
            parser.showWarnings(true);
            // parse the document
            parser.parse(url);

            // Obtain the document
            XMLDocument doc = parser.getDocument();

            // print document elements
            System.out.print("The elements are: ");
            printElements(doc);

            // print document elements attributes
            System.out.println("The attributes of each element are: ");
            printElementAttributes(doc);

        } catch (Exception e) {
            System.out.println(e.toString());
        }
    }

    /*
     * +---------------------------------------------+
     * | METHOD: printElements                       |
     * +---------------------------------------------+
     */
    static void printElements(Document doc) {

        NodeList nodelist = doc.getElementsByTagName("*");
        Node     node;

        for (int i=0; i<nodelist.getLength(); i++) {
            node = nodelist.item(i);
            System.out.print(node.getNodeName() + " ");
        }

        System.out.println();

    }

    /*
     * +---------------------------------------------+
     * | METHOD: printElementAttributes              |
     * +---------------------------------------------+
     */
    static void printElementAttributes(Document doc) {

        NodeList      nodelist = doc.getElementsByTagName("*");
        Node          node;
        Element       element;
        NamedNodeMap  nnm = null;

        String attrname;
        String attrval;
        int    i,len;

        len = nodelist.getLength();

        for (int j=0; j < len; j++) {
            element = (Element)nodelist.item(j);
            System.out.println(element.getTagName() + ":");
            nnm = element.getAttributes();
        }

        if (nnm != null) {
            for (i=0; i<nnm.getLength(); i++) {
                node = nnm.item(i);
                attrname = node.getNodeName();
                attrval  = node.getNodeValue();
                System.out.println(" " + attrname + " = " + attrval);
            }
        }

        System.out.println();

    }

    /*
     * +---------------------------------------------+
     * | METHOD: createURL                           |
     * +---------------------------------------------+
     */
    static URL createURL(String filename) {

        URL url = null;

        try {
            url = new URL(filename);
        } catch (MalformedURLException ex) {
            try {
                File f = new File(filename);
                url = f.toURL();
            } catch (MalformedURLException e) {
                System.out.println("Cannot create URL for: " + filename);
                System.exit(0);
            }
        }

        return url;

    }

}