BookRank.java Source code

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Here is the source code for BookRank.java

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/*
 * Copyright (c) Ian F. Darwin, http://www.darwinsys.com/, 1996-2002.
 * All rights reserved. Software written by Ian F. Darwin and others.
 * $Id: LICENSE,v 1.8 2004/02/09 03:33:38 ian Exp $
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS''
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 * 
 * Java, the Duke mascot, and all variants of Sun's Java "steaming coffee
 * cup" logo are trademarks of Sun Microsystems. Sun's, and James Gosling's,
 * pioneering role in inventing and promulgating (and standardizing) the Java 
 * language and environment is gratefully acknowledged.
 * 
 * The pioneering role of Dennis Ritchie and Bjarne Stroustrup, of AT&T, for
 * inventing predecessor languages C and C++ is also gratefully acknowledged.
 */

import java.io.BufferedReader;
import java.io.FileWriter;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.URL;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Properties;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

/**
 * Graph of a book's sales rank on a given bookshop site.
 * 
 * @author Ian F. Darwin, http://www.darwinsys.com/, Java Cookbook author,
 *         originally translated fairly literally from Perl into Java.
 * @author Patrick Killelea <p@patrick.net>: original Perl version, from the 2nd
 *         edition of his book "Web Performance Tuning".
 * @version $Id: BookRank.java,v 1.8 2004/03/20 20:48:03 ian Exp $
 */
public class BookRank {
    public final static String DATA_FILE = "book.sales";

    public final static String GRAPH_FILE = "book.png";

    /** Grab the sales rank off the web page and log it. */
    public static void main(String[] args) throws Exception {

        Properties p = new Properties();
        String title = p.getProperty("title", "NO TITLE IN PROPERTIES");
        // The url must have the "isbn=" at the very end, or otherwise
        // be amenable to being string-catted to, like the default.
        String url = p.getProperty("url", "http://test.ing/test.cgi?isbn=");
        // The 10-digit ISBN for the book.
        String isbn = p.getProperty("isbn", "0000000000");
        // The RE pattern (MUST have ONE capture group for the number)
        String pattern = p.getProperty("pattern", "Rank: (\\d+)");

        // Looking for something like this in the input:
        //    <b>QuickBookShop.web Sales Rank: </b>
        //    26,252
        //    </font><br>

        Pattern r = Pattern.compile(pattern);

        // Open the URL and get a Reader from it.
        BufferedReader is = new BufferedReader(new InputStreamReader(new URL(url + isbn).openStream()));
        // Read the URL looking for the rank information, as
        // a single long string, so can match RE across multi-lines.
        String input = "input from console";
        // System.out.println(input);

        // If found, append to sales data file.
        Matcher m = r.matcher(input);
        if (m.find()) {
            PrintWriter pw = new PrintWriter(new FileWriter(DATA_FILE, true));
            String date = // `date +'%m %d %H %M %S %Y'`;
                    new SimpleDateFormat("MM dd hh mm ss yyyy ").format(new Date());
            // Paren 1 is the digits (and maybe ','s) that matched; remove comma
            Matcher noComma = Pattern.compile(",").matcher(m.group(1));
            pw.println(date + noComma.replaceAll(""));
            pw.close();
        } else {
            System.err.println("WARNING: pattern `" + pattern + "' did not match in `" + url + isbn + "'!");
        }

        // Whether current data found or not, draw the graph, using
        // external plotting program against all historical data.
        // Could use gnuplot, R, any other math/graph program.
        // Better yet: use one of the Java plotting APIs.

        String gnuplot_cmd = "set term png\n" + "set output \"" + GRAPH_FILE + "\"\n" + "set xdata time\n"
                + "set ylabel \"Book sales rank\"\n" + "set bmargin 3\n" + "set logscale y\n"
                + "set yrange [1:60000] reverse\n" + "set timefmt \"%m %d %H %M %S %Y\"\n" + "plot \"" + DATA_FILE
                + "\" using 1:7 title \"" + title + "\" with lines\n";

        Process proc = Runtime.getRuntime().exec("/usr/local/bin/gnuplot");
        PrintWriter gp = new PrintWriter(proc.getOutputStream());
        gp.print(gnuplot_cmd);
        gp.close();
    }
}