Untitled

import components.simplereader.SimpleReader;
import components.simplereader.SimpleReader1L;
import components.simplewriter.SimpleWriter;
import components.simplewriter.SimpleWriter1L;
import components.xmltree.XMLTree;
import components.xmltree.XMLTree1;

/**
 * Program to convert an XML RSS (version 2.0) feed from a given URL into the
 * corresponding HTML output file.
 *
 * @author Put your name here
 *
 */
public final class RSSReader {

    /**
     * Private constructor so this utility class cannot be instantiated.
     */
    private RSSReader() {
    }

    /**
     * Outputs the "opening" tags in the generated HTML file. These are the
     * expected elements generated by this method:
     *
     * <html>
     * <head>
     * <title>the channel tag title as the page title</title>
     * </head>
     * <body>
     *  <h1>the page title inside a link to the <channel> link<h1>
     *  <p>the channel description</p>
     *  <table>
     *   <tr>
     *    <th>Date</th>
     *    <th>Source</th>
     *    <th>News</th>
     *   </tr>
     *
     * @param channel
     *            the channel element XMLTree
     * @param out
     *            the output stream
     * @updates out.content
     * @requires [the root of channel is a <channel> tag] and out.is_open
     * @ensures out.content = #out.content * [the HTML "opening" tags]
     */
    private static void outputHeader(XMLTree channel, SimpleWriter out) {
        assert channel != null : "Violation of: channel is not null";
        assert out != null : "Violation of: out is not null";
        assert channel.isTag() && channel.label().equals("channel") : ""
                + "Violation of: the label root of channel is a <channel> tag";
        assert out.isOpen() : "Violation of: out.is_open";
        int location = 0;
        out.println("<html>");
        out.println("<head>");
        out.println("<title>" + channel.child(getChildElement(channel, "title")).child(0) +"</title>");
        out.println("</head>");
        out.println("<body>");
        out.println("<h1>");
        location = getChildElement(channel,"link");
        int location2 =  getChildElement(channel,"title");
        out.println("a href =\""   + channel.child(location2).child(0) +"\">" );
        out.print( channel.child(location).child(0)+"</a>");
        out.println("</h1>");

        out.println("<p>");
        location = getChildElement(channel,"description");
        out.println("\""   + channel.child(location).child(0) +"\"" );
        out.println("</p>");
        out.println("<table border=\"1\">");
        out.println("<tbody>");
        out.println("<tr>");
        out.println("<th>Date</th>");
        out.println("<th>Source</th>");
        out.println("<th>News</th>");
        out.println("</tr>");
     // get the tree for each item
        for(int i = 3; i < channel.numberOfChildren(); i++)
        {
        	XMLTree items = channel.child(i);
        	processItem(items,out);
        }

        outputFooter(out);


    }

    /**
     * Outputs the "closing" tags in the generated HTML file.  These are the
     * expected elements generated by this method:
     *
     *  </table>
     * </body>
     * </html>
     *
     * @param out
     *            the output stream
     * @updates out.contents
     * @requires out.is_open
     * @ensures out.content = #out.content * [the HTML "closing" tags]
     */
    private static void outputFooter(SimpleWriter out) {
        assert out != null : "Violation of: out is not null";
        assert out.isOpen() : "Violation of: out.is_open";

        out.println("</tbody>");
        out.println("</table>");
        out.println("</body>");
        out.println("</html>");
    }

    /**
     * Finds the first occurrence of the given tag among the children of the
     * given {@code XMLTree} and return its index; returns -1 if not found.
     *
     * @param xml
     *            the {@code XMLTree} to search
     * @param tag
     *            the tag to look for
     * @return the index of the first child of type tag of the {@code XMLTree}
     *         or -1 if not found
     * @requires [the label of the root of xml is a tag]
     * @ensures <pre>
     * getChildElement =
     *  [the index of the first child of type tag of the {@code XMLTree} or
     *   -1 if not found]
     * </pre>
     */
    private static int getChildElement(XMLTree xml, String tag) {
        assert xml != null : "Violation of: xml is not null";
        assert tag != null : "Violation of: tag is not null";
        assert xml.isTag() : "Violation of: the label root of xml is a tag";
        int index = -1;
        int i = 0;
        int childCount = xml.numberOfChildren();
        if(xml.numberOfChildren() != 0)
        {
        	while(i <= childCount)
        	{
        		if(xml.child(i).label().equals(tag))
        		{
        			index = i;
        		}
        		i++;

        	}
        }

        return index;
    }

    /**
     * Processes one news item and outputs one table row. The row contains three
     * elements: the publication date, the source, and the title (or
     * description) of the item.
     *
     * @param item
     *            the news item
     * @param out
     *            the output stream
     * @updates out.content
     * @requires <pre>
     * [the label of the root of item is an <item> tag] and out.is_open
     * </pre>
     * @ensures <pre>
     * out.content = #out.content *
     *   [an HTML table row with publication date, source, and title of news item]
     * </pre>
     */
    private static void processItem(XMLTree item, SimpleWriter out) {
        assert item != null : "Violation of: item is not null";
        assert out != null : "Violation of: out is not null";
        assert item.isTag() && item.label().equals("item") : ""
                + "Violation of: the label root of item is an <item> tag";
        assert out.isOpen() : "Violation of: out.is_open";
        	String pubDate;
        	String titledesc;
        	String source;
        	String sourceURL = null;
        	String titleURL;

        		// get the pubdate
        		int childIndex = getChildElement(item,"pubDate");
        		if(childIndex > -1)
        		{
        			pubDate = "No date available";
        		}
        		else
        		{
        			pubDate = item.child(childIndex).label();
        		}

        		//get the source
        		int childIndex2 = getChildElement(item,"source");
        		if(childIndex2 > -1)
        		{
        			source = "No source available";
        		}
        		else
        		{
        			source = item.child(childIndex2).label();
        			sourceURL = item.child(childIndex2).attributeValue("url"); // URL FOR SOURCE

        		}
        		// source has attribute url


        		// get the title or description
        		int lIndex = getChildElement(item,"link");
        		titleURL = item.child(lIndex).label(); // URL FOR TITLE/DESCRIPTION
        		if(getChildElement(item,"title") > -1)
        		{
            		int childIndex3 = getChildElement(item,"description");
            		titledesc = item.child(childIndex3).label();
        		}
        		else if(getChildElement(item,"description") > -1)
        		{
        			int childIndex3 = getChildElement(item,"title");
            		titledesc = item.child(childIndex3).label();
        		}
        		else
        		{
        			titledesc = "No title or description available";
        		}

        		out.print("<td>");
        		out.print(pubDate);
        		out.print("</td>");
        		out.println();
        		out.print("<td>");
        		out.print(source);
                out.println("a href =\""   + sourceURL +"\">" );
                out.print( source +"</a>");
        		out.print("</td>");
        		out.println();
        		out.print("<td>");
                out.println("a href =\""   + titleURL +"\">" );
                out.print( titledesc +"</a>");
        		out.print("</td>");


    }

    /**
     * Main method.
     *
     * @param args
     *            the command line arguments; unused here
     */
    public static void main(String[] args) {
        SimpleReader in = new SimpleReader1L();
        SimpleWriter out = new SimpleWriter1L();

        out.println("Please enter the URL of an XML feed");
        String url = in.nextLine();
        XMLTree xml = new XMLTree1(url);
        xml = xml.child(0);

        out.println("Please enter the name of an output file");
        String userOutFile = in.nextLine();
        SimpleWriter outputFile = new SimpleWriter1L(userOutFile);


        outputHeader(xml,outputFile);

        in.close();
        out.close();
    }

}