librarysystem.java

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import java.io.*;
import java.util.*;

/**
 * This class implements a library system.
 *
 * @author author name
 * @version 1.1.0
 * @see CatalogItem
 * @see Book
 * @see Recording
 * @see Catalog
 * @see Borrower
 * @see BorrowerDatabase
 * @see BorrowersFormatter
 * @see PlainTextBorrowersFormatter
 * @see HTMLBorrowersFormatter
 * @see XMLBorrowersFormatter
 */
public class LibrarySystem  {

    private static BufferedReader  stdIn =
        new  BufferedReader(new  InputStreamReader(System.in));
    private static PrintWriter  stdOut =
        new  PrintWriter(System.out, true);
    private static PrintWriter  stdErr =
        new  PrintWriter(System.err, true);

    private BorrowerDatabase borrowerDB;

    private BorrowersFormatter borrowersFormatter;

    /**
     * Loads a library catalog and borrower database and then
     * starts the application.
     *
     * @param args  String arguments.  Not used.
     * @throws IOException if there are errors in the input.
     */
    public static void  main(String[]  args) throws IOException {

        LibrarySystem  app = new  LibrarySystem();

        app.run();
    }

    /**
     * Creates a <code>LibrarySystem</code> object.
     */
    private LibrarySystem() {

        borrowerDB = loadBorrowers(loadCatalog());
        borrowersFormatter =
            PlainTextBorrowersFormatter.getSingletonInstance();
    }

    /**
     * Loads catalog data.
     */
    private Catalog loadCatalog() {

        Catalog catalog = new Catalog();

        catalog.addItem(new Book("B001",
                                 "Effective Java Programming", 2001,
                                 "Joshua Bloch", 252));
        catalog.addItem(new Book("B002",
                                 "Design Patterns", 1995,
                                 "Erich Gamma et al", 395));
        catalog.addItem(new Book("B003",
                                 "Refactoring", 1999,
                                 "Martin Fowler", 431));
        catalog.addItem(new Book("B004",
                                 "The Mythical Man-Month", 1995,
                                 "Frederick P. Brooks", 322));
        catalog.addItem(new Book("B005",
                                 "Code Complete", 1993,
                                 "Steve C McConnell", 857));
        catalog.addItem(new Book("B006",
                                 "The Psychology of Comp. Progr.", 1998,
                                 "Gerald M. Weinberg", 360));
        catalog.addItem(new Book("B007",
                                 "Programming Pearls ", 1999,
                                 "Jon Bentley", 239));
        catalog.addItem(new Book("B008",
                                 "The Practice of Programming", 1999,
                                 "Brian W. Kernighan", 257));
        catalog.addItem(new Book("B009",
                                 "Peopleware", 1999,
                                 "Tom Demarco", 245));
        catalog.addItem(new Book("B010",
                                 "The Java Programming Language", 2000,
                                 "Ken Arnold", 595));
        catalog.addItem(new Book("B011",
                                 "Core J2EE Patterns", 2001,
                                 "Deepak Alur", 496));
        catalog.addItem(new Book("B012",
                                 "Rapid Development", 1996,
                                 "Steve C McConnell", 680));
        catalog.addItem(new Book("B013",
                                 "Applying UML and Patterns", 2001,
                                 "Craig Larman", 656));
        catalog.addItem(new Book("B014",
                                 "The Little Schemer", 1995,
                                 "Daniel P. Friedman", 216));
        catalog.addItem(new Book("B015",
                                 "Agile Software Development", 2001,
                                 "Alistair Cockburn", 256));
        catalog.addItem(new Recording("R001",
                                      "Getz/Gilberto", 1963,
                                      "Stan Getz and Joo Gilberto", "CD"));
        catalog.addItem(new Recording("R002",
                                      "Kind of Blue", 1997,
                                      "Miles Davis", "CD"));
        catalog.addItem(new Recording("R003",
                                      "Supernatural", 1999, "Santana",
                                      "Tape"));
        catalog.addItem(new Recording("R004",
                                      "Private Collection", 1983,
                                      "Jon & Vangelis", "Tape"));
        catalog.addItem(new Recording("R005",
                                      "Abbey Road", 1969,
                                      "Beatles", "CD"));
        catalog.addItem(new Recording("R006",
                                      "Joshua Tree", 1990,
                                      "U2", "CD"));

        return catalog;
    }

    /**
     * Loads a borrower database.
     */
    private BorrowerDatabase loadBorrowers(Catalog catalog) {

        BorrowerDatabase borrowerDB = new BorrowerDatabase();

        Borrower borrower = new Borrower("ID001", "James Addy");

        borrower.getBorrowedItems().addItem(
            catalog.getItem("B003"));
        borrower.getBorrowedItems().addItem(
            catalog.getItem("R001"));
        borrower.getBorrowedItems().addItem(
            catalog.getItem("B012"));
        borrowerDB.addBorrower(borrower);

        borrower = new Borrower("ID002", "John Doust");
        borrowerDB.addBorrower(borrower);

        borrower = new Borrower("ID003", "Constance Foster");
        borrower.getBorrowedItems().addItem(
            catalog.getItem("B006"));
        borrowerDB.addBorrower(borrower);

        borrower = new Borrower("ID004", "Harold Gurske");
        borrower.getBorrowedItems().addItem(
            catalog.getItem("B002"));
        borrowerDB.addBorrower(borrower);

        borrower = new Borrower("ID005", "Mary A. Rogers");
        borrowerDB.addBorrower(borrower);

        borrower = new Borrower("ID006", "Laura Novelle");
        borrower.getBorrowedItems().addItem(
            catalog.getItem("B007"));
        borrower.getBorrowedItems().addItem(
            catalog.getItem("B009"));
        borrowerDB.addBorrower(borrower);

        borrower = new Borrower("ID007", "David M. Prescott");
        borrower.getBorrowedItems().addItem(
            catalog.getItem("B011"));
        borrowerDB.addBorrower(borrower);

        borrower = new Borrower("ID008", "Francis Matthews");
        borrower.getBorrowedItems().addItem(
            catalog.getItem("R003"));
        borrower.getBorrowedItems().addItem(
            catalog.getItem("B005"));
        borrowerDB.addBorrower(borrower);

        borrower = new Borrower("ID009", "Thomas Ferris");
        borrowerDB.addBorrower(borrower);

        borrower = new Borrower("ID010", "John Johnson");
        borrower.getBorrowedItems().addItem(
            catalog.getItem("B004"));
        borrowerDB.addBorrower(borrower);

        return borrowerDB;
    }

    /**
     * Presents the user with a menu of options and executes the
     * selected task.
     */
    private void run() throws IOException  {

        int  choice = getChoice();

        while (choice != 0)  {

            if (choice == 1)  {
                setBorrowersFormatter(
                    PlainTextBorrowersFormatter.getSingletonInstance());
            } else if (choice == 2)  {
                setBorrowersFormatter(
                    HTMLBorrowersFormatter.getSingletonInstance());
            } else if (choice == 3)  {
                setBorrowersFormatter(
                    XMLBorrowersFormatter.getSingletonInstance());
            }
            displayBorrowers();

            choice = getChoice();
        }
    }

    /**
     * Displays a menu of options and verifies the user's choice.
     *
     * @return an integer in the range [0,3]
     */
    private int  getChoice() throws IOException  {

        int  input;

        do  {
            try  {
                stdErr.println();
                stdErr.print("[0]  Quit\n"
                             + "[1]  Display Plain Text\n"
                             + "[2]  Display HTML\n"
                             + "[3]  Display XML\n"
                             + "choice> ");
                stdErr.flush();

                input = Integer.parseInt(stdIn.readLine());

                stdErr.println();

                if (0 <= input && 3 >= input)  {
                    break;
                } else {
                    stdErr.println("Invalid choice:  " + input);
                }
            } catch (NumberFormatException  nfe)  {
                stdErr.println(nfe);
            }
        }  while (true);

        return  input;
    }

    /**
     * Changes the format in which the borrower database will be
     * displayed.
     *
     * @param newFormatter format in which the borrower database will
     *                     be displayed.
     */
    private void setBorrowersFormatter(
        BorrowersFormatter newFormatter) {

        borrowersFormatter = newFormatter;
    }

    /**
     * Displays the borrowers in the current format.
     */
    private void displayBorrowers() {

        stdOut.println(
            borrowersFormatter.formatBorrowers(borrowerDB));
    }
}