gcc/libjava/javax/swing/SpinnerDateModel.java

/* SpinnerDateModel.java --
   Copyright (C) 2002, 2004 Free Software Foundation, Inc.

This file is part of GNU Classpath.

GNU Classpath is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
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General Public License for more details.

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02111-1307 USA.

Linking this library statically or dynamically with other modules is
making a combined work based on this library.  Thus, the terms and
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As a special exception, the copyright holders of this library give you
permission to link this library with independent modules to produce an
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package javax.swing;

import java.io.Serializable;
import java.util.Calendar;
import java.util.Date;

/**
 * SpinnerDateModel
 *
 * Implements a SpinnerModel for dates, rotating a calendar field such as 
 * month, year, day, week, hour, minute.
 *
 * @author Sven de Marothy
 * @version 0.1 (first implementation)
 */
public class SpinnerDateModel extends AbstractSpinnerModel
  implements Serializable
{
  private Calendar date;
  private Comparable start;
  private Comparable end;
  private int calendarField;

  /**
   * For compatability with Sun's JDK
   * FIXME: what's the number? And which fields should be serialized?
   */
  private static final long serialVersionUID = 1L;

  /**
   * Constructs a SpinnerDateModel using the current date,
   * no start or end limit, and Calendar.DAY_OF_MONTH as the calendar field.
   */
  public SpinnerDateModel()
  {
    this(new Date(), null, null, Calendar.DAY_OF_MONTH);
  }

  /**
   * Constructs a SpinnerDateModel which spins a given calendar field,
   * using a given date and start and end date limits.
   * @param value - the initial Date value
   * @param start - start limit, as a Date object, or <code>null</code>
   * for no lower limit.
   * @param end - end limit, or <code>null</code> for no upper limit.
   * @param calendarField - the <code>Calendar</code> field to spin,
   * (Calendar.ZONE_OFFSET and Calendar.DST_OFFSET are invalid)
   */
  public SpinnerDateModel(Date value, Comparable start, Comparable end,
                          int calendarField)
  {
    date = Calendar.getInstance();
    date.setTime(value);
    this.start = start;
    this.end = end;
    setCalendarField(calendarField);
  }

  /**
   * Returns the value of the Calendar field to spin.
   */
  public int getCalendarField()
  {
    return calendarField;
  }

  /**
   * Returns the current date in the sequence.
   * @return a <code>Date</code> object.
   */
  public Date getDate()
  {
    return date.getTime();
  }

  /**
   * Returns the starting limit of the SpinnerModel.
   * @return a Date object, or <code>null</code> if there is no limit.
   */
  public Comparable getStart()
  {
    return start;
  }

  /**
   * Returns the end limit of the SpinnerModel.
   * @return a Date object, or <code>null</code> if there is no limit.
   */
  public Comparable getEnd()
  {
    return end;
  }

  /**
   * Returns the current date in the sequence,
   * this method returns the same as <code>getDate()</code>.
   * @return a <code>Date</code> object.
   */
  public Object getValue()
  {
    return date.getTime();
  }

  /**
   * Returns the next date in the sequence, or <code>null</code> if the
   * next date is equal to or past the end limit.
   * @return a Date object, or <code>null</code>.
   */
  public Object getNextValue()
  {
    Calendar nextCal = Calendar.getInstance();
    nextCal.setTime(date.getTime());
    nextCal.roll(calendarField, true);
    Date nextDate = nextCal.getTime();
    if (end != null)
      if (end.compareTo(nextDate) < 0)
	return null;
    return nextDate;
  }

  /**
   * Returns the previous date in the sequence, or <code>null</code> if the
   * next date is equal to or past the end limit.
   * @return a Date object, or <code>null</code>.
   */
  public Object getPreviousValue()
  {
    Calendar prevCal = Calendar.getInstance();
    prevCal.setTime(date.getTime());
    prevCal.roll(calendarField, false);
    Date prevDate = prevCal.getTime();
    if (end != null)
      if (end.compareTo(prevDate) > 0)
	return null;
    return prevDate;
  }

  /**
   * Sets the date field to change. It must be a valid Calendar field,
   * excluding Calendar.ZONE_OFFSET and Calendar.DST_OFFSET.
   * @param calendarField - the calendar field to set.
   */
  public void setCalendarField(int calendarField)
  {
    if (calendarField < 0 || calendarField >= Calendar.FIELD_COUNT
        || calendarField == Calendar.ZONE_OFFSET
        || calendarField == Calendar.DST_OFFSET)
      throw new IllegalArgumentException("Illegal calendarField");

    if (this.calendarField != calendarField)
      {
	this.calendarField = calendarField;
	fireStateChanged();
      }
  }

  /**
   * Sets the starting date limit for the sequence.
   *
   * @param start - a Date object of the limit date,
   * or <code>null</code> for no limit.
   */
  public void setStart(Comparable start)
  {
    if (this.start != start)
      {
	this.start = start;
	fireStateChanged();
      }
  }

  /**
   * Sets the end date limit for the sequence.
   *
   * @param end - a Date object of the limit date,
   * or <code>null</code> for no limit.
   */
  public void setEnd(Comparable end)
  {
    if (this.end != end)
      {
	this.end = end;
	fireStateChanged();
      }
  }

  /**
   * Sets the current date in the sequence.
   *
   * @param value - a Date object.
   */
  public void setValue(Object value)
  {
    if (! (value instanceof Date) || value == null)
      throw new IllegalArgumentException("Value not a date.");
    date.setTime((Date) value);
    fireStateChanged();
  }
}