/**********************************************************
 * Newspaper accepts an author name and prints out the article title.
 * Kelli Wiseth
 * 24-October-2004
 * Mid-term Exam
 *
 * XML and Web Services class | NDNU 
 *
 ***********************************************************
 */
 
// Java core packages
import java.io.*;

// Java standard extensions
import javax.xml.parsers.*;
import javax.xml.transform.*;

// third-party libraries
import org.w3c.dom.*;
import org.w3c.dom.traversal.*; 
import org.xml.sax.*;

public class Newspaper 
{
   String author;
   String filename = "newspaper.xml";
   String nodeValue = " ";
   boolean authorExists = false;

   DocumentBuilder newspaperParser;
   Document newspaper;
   Element root;
   Node nodeName;
      
   public Newspaper ( String authorFirst, String authorLast )
   {
   String authorLookup = authorFirst + " " + authorLast;
   
   
   // parse XML, create DOM tree, and find the author
   try 
   {

   // obtain default parser
   DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
   dbf.setValidating( false );

   DocumentBuilder newspaperParser = dbf.newDocumentBuilder();
   Document newspaper = newspaperParser.parse( new File( filename ) );
   newspaper.getDocumentElement().normalize();

   NodeList articles = newspaper.getElementsByTagName("ARTICLE");
   NodeList headlines = newspaper.getElementsByTagName("HEADLINE");
   
   for (int x = 0; x < articles.getLength(); x++)
       {
        Element articleElement = (Element)articles.item(x);
        String authorElement = articleElement.getAttribute("AUTHOR");
        Element headlineElement = (Element)headlines.item(x);
          if (authorElement.equalsIgnoreCase(authorLookup))
          {
             authorExists=true;
             Node headlineText = headlineElement.getFirstChild();
             System.out.println("The author " + authorLookup + " wrote \"" + headlineText.getNodeValue() + ".\"");
           }
        }

   if (!authorExists) 
      System.out.println("No articles for author named " + authorLookup +
                       " found in the newspaper.");

   
   } //close try block
   
   /* The parser exceptions aren't needed, since we're not creating a 
    * DOM structure except by passing in a pre-validated XML file, and
    * we've turned off validation to validate against,  raise any of 
    * these exceptions in this program. The IOException is raised any 
    * time the filename is incorrect.
   */
   
   
   // handle exception thrown by DocumentBuilder
   catch ( ParserConfigurationException parserException ) 
   {
   parserException.printStackTrace();
   }
      
   // handle exception thrown by Parser
   catch ( SAXException saxException ) 
   {
   saxException.printStackTrace();         
   }
      
   // handle exception thrown when reading data from file
   catch ( IOException ioException ) 
   {
   System.out.println();
   System.out.println("Try entering the adddress book filename again. ");
   System.out.println("There's something wrong with the name you entered.");
   System.exit( 1 );
   }
 
  } //close constructor
  
   public static void main( String args[] )
   {
    if ( args.length < 2 ) 
       {
        System.out.print("Syntax: java Newspaper <author> \n");
        System.out.print("Please enter author's first and last name, as in: \n\n");
        System.out.print("              java Newspaper herb caen \n");
        System.exit( 1 );
        }
    Newspaper report = new Newspaper ( args[0], args[1] );
  
   }//close main method
   
} //close class Newspaper