dbutilities.java

基于Java的软件信息系统－项目管理

package db;

import java.text.*;
import java.util.*;

public class DBUtilities
{
    // Date utilities

    private static DateFormat s_dateFormatter =
	new SimpleDateFormat ("MM/dd/yy");

    public static String formatDate (java.util.Date date)
    {
	return s_dateFormatter.format (date);
    }

    public static java.util.Date parseDate (String dateString)
	throws ParseException
    {
	return s_dateFormatter.parse (dateString);
    }

    // Utilities for display results from the Reservations table

    public static void displayReservation (Reservation res)
    {
	System.out.println ("Reservation ID: " + res.getId());
	System.out.println ("Customer: " + res.getFirstName() + " " + 
			    res.getLastName());
	System.out.println ("Arrival date: " + 
			    s_dateFormatter.format(res.getDate ()));
	System.out.println ("Staying: " + res.getDays());
	System.out.println ("# of guests: " + res.getGuests());
	System.out.println ("Class of room: " + res.getRoomType());
    }

    public static void displayReservations (List reservations)
    {
	for (Iterator iter = reservations.iterator ();
	     iter.hasNext(); )
       {
	    displayReservation ((Reservation)iter.next());
	    System.out.println ();
	}
    }

    public static List toList (Collection coll)
    {
        List ans = new ArrayList ();
        Iterator iter = coll.iterator ();
        while (iter.hasNext())
            ans.add (iter.next());
        return ans;
    }

    public static String rootPath ()
    {
        try
        {
            Class dbClass = Class.forName ("db.DBUtilities");
            ClassLoader loader = dbClass.getClassLoader();
            java.net.URL url = loader.getResource ("db/DBUtilities.class");
            String classFile = url.getFile();
            StringBuffer rootPathBuffer = new StringBuffer(classFile.substring (0, classFile.lastIndexOf ("/db")));
            rootPathBuffer = rootPathBuffer.deleteCharAt (0);
            replace(rootPathBuffer, "/", "\\");
            replace(rootPathBuffer, "%20", " ");
            return rootPathBuffer.toString();
        } catch (ClassNotFoundException e)
        {
            System.err.println ("DBUtilities class not found. Impossible!");
            System.exit(0);
        }
        return null;
    }

    public static void replace (StringBuffer buf, String oldStr, String newStr)
    {
        int index = 0;
        int oldStrLen = oldStr.length();
        int newStrLen = newStr.length();
        int newIndex = -1;
        while ((newIndex = buf.indexOf (oldStr, index)) > 0)
        {
            buf.delete (newIndex, newIndex+oldStrLen);
            buf.insert (newIndex, newStr);
            index = newIndex + newStrLen;
        }
    }
}