vacdateutil.java

主要是航空预订系统

package com.air.util;

import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
import java.util.TimeZone;

/**
 * @author Jelly Yang, create on Nov 19, 2008
 *
 * VacDateUtil
 */
public final class VacDateUtil
{
	private final DateFormat formater;
	private final DateFormat dbformater;
	/**
	 * private constructor of VacDateUtil, prevent instantiation
	 */
	private VacDateUtil()
	{
		formater= new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
		formater.setLenient(true);
		dbformater= new SimpleDateFormat("MM/dd/yyyy");
		dbformater.setLenient(true);
	}
	private static class VacDateUtilHolder
	{
		static final VacDateUtil vacDateUtil = new VacDateUtil();
	}
	/**
	 * @return an instance of VacDateUtil
	 */
	public static VacDateUtil getInstance()
	{
		return VacDateUtilHolder.vacDateUtil;
	}
	public Date convertFromString( String datestr )
	{
		Date date = null;
		try
		{
			TimeZone tz = TimeZone.getDefault();
			formater.setTimeZone(tz);
			date = formater.parse(datestr);
		}
		catch( Exception ex )
		{
		}
		return date;
	}
	public Date convertFormStrDate( String datestr )
	{
		Date date = null;
		try
		{
			TimeZone tz = TimeZone.getDefault();
			dbformater.setTimeZone(tz);
			date = dbformater.parse(datestr);
		}
		catch( Exception ex )
		{
		}
		return date;
	}
	public String convertFromDate( Date date )
	{
		return dbformater.format(date);
	}
	public int calcUseddays( Date startdate, Date enddate )
	{
		int useddays = 0;
		try
		{
			long diff = enddate.getTime() - startdate.getTime();
			useddays = ( int )( diff/(24L*60L*60L*1000L));
			DateFormat formater = new SimpleDateFormat("zz");
			String startdatestr = (formater.format(startdate)).trim();
			String enddatestr = (formater.format(enddate)).trim();
			if( !( startdatestr.equalsIgnoreCase(enddatestr)))
			{
				if(("EST").equalsIgnoreCase(startdatestr))
				{
					useddays = useddays + 1;
				}
			}
			useddays = useddays + 1;
		}
		catch( Exception ex )
		{
			
		}
		return useddays;
	}
	public double calcdiffdays( Date startdate, Date enddate )
	{
		int diffdays = calcUseddays( startdate, enddate );
		Double doubleobj = new Double(diffdays);
		return doubleobj.doubleValue();
	}
	public boolean isInDateRange( Date startdate, Date enddate, Date verifydate )
	{
		boolean flag = false;
		if( ( ( verifydate.after( startdate) ) || (verifydate.equals(startdate)) ) && ( ( verifydate.before( enddate) ) || (verifydate.equals(enddate)) ) )
		{
			flag = true;
		}
		return flag;
	}
	public boolean isAfterNow( Date date )
	{
		return date.after(getToday());
	}
	public boolean isBeforeNow( Date date )
	{
		return date.before(getToday());
	}
	public boolean isEqualNow( Date date )
	{
		return date.equals(getToday());
	}
	public Date getToday()
	{
		Calendar calnow = Calendar.getInstance();
		calnow.set( Calendar.HOUR,0);
		calnow.set( Calendar.MINUTE,0);
		calnow.set( Calendar.SECOND,0);
		calnow.set( Calendar.MILLISECOND,0);
		Date today = calnow.getTime();
		return today;
	}
	public int getCurrentYear()
	{
		Calendar calnow = Calendar.getInstance();
		int currentyear = calnow.get( Calendar.YEAR);
		return currentyear;
	}
	public String dbString( Date date)
	{
		String datestr = convertFromDate(date);
		return "to_date('" + datestr + "', 'mm/dd/yyyy')";
	}
}