MIDP中对日期时间的简单转换

MIDP的Date和Calendar类都是J2SE的精简版，也没有SimpleDateFormat之类的格式化类，因此，写了一个简单的DateTime类实现本地日期和时间的格式化。

package com.crackj2ee.midp.util;

import Java.util.*;

public final class DateTime {

private static String[] WEEKDAYS = {"SUN", "MON", "TUE", "WED", "THU", "FRI", "SAT"};

public final String timeZone;

public final int year;

public final int month;

public final int day;

public final int weekday;

public final int hour;

public final int minute;

public final int second;

public DateTime(Date date, String timeZone) {

this.timeZone = timeZone;

Calendar c = timeZone==null ? Calendar.getInstance() : Calendar.getInstance(TimeZone.getTimeZone(timeZone));

c.setTime(date);

year = c.get(Calendar.YEAR);

month = c.get(Calendar.MONTH);

day = c.get(Calendar.DAY_OF_MONTH);

weekday = c.get(Calendar.DAY_OF_WEEK);

hour = c.get(Calendar.HOUR_OF_DAY);

minute = c.get(Calendar.MINUTE);

second = c.get(Calendar.SECOND);

}

public DateTime(long time, String timeZone) {

this(new Date(time), timeZone);

}

public Date toDate() {

Calendar c = Calendar.getInstance(TimeZone.getTimeZone(timeZone));

c.set(Calendar.YEAR, year);

c.set(Calendar.MONTH, month);

c.set(Calendar.DAY_OF_MONTH, day);

c.set(Calendar.HOUR_OF_DAY, hour);

c.set(Calendar.MINUTE, minute);

c.set(Calendar.SECOND, second);

return c.getTime();

}

public String toDateString() {

return year + "-" + (month+1) + "-" + day + "(" + WEEKDAYS[weekday-1] + ")";

}

public String toTimeString() {

return hour + ":" + minute + ":" + second;

}

public String toString() {

return toDateString() + " " + toTimeString();

}

}

示例：

输出当前日期和时间：new DateTime(new Date(), "GMT+8").toString();

转换到Date对象：toDate();

注意，要指定时区，否则时间永远是GMT标准时间。可以在Windows时区设置中查询，北京时间是"GMT+8"

（出处：http://www.knowsky.com）