API学习GregorianCalendar

Bertha 。 2022-06-10 06:45 171阅读 0赞

package com.wonders.api.date;
    
    import java.util.Calendar;
    import java.util.Date;
    import java.util.GregorianCalendar;
    import java.util.SimpleTimeZone;
    import java.util.TimeZone;
    
    /**
     * JDK1.7
     * GregorianCalendar类
     * (1)GregorianCalendar是一个具体的日历子类，它提供了大多数世界使用的标准日历系统
     * (2)GregorianCalendar是一个混合日历，它支持Julian和Gregorian的日历系统，支持单一的不连续性，它对应于公历在公历建立时(在某些国家的1582年10月15日，后来在其他国家)的公历日期。
     * (3)通过调用setGregorianChange()可以对日期进行转换。
     * @author liyongyong
     *
     */
    public class GregorianCalendarTest {
    
    	public static void main(String[] args) {
    		GregorianCalendar g = new GregorianCalendar();
    		/**
    		 * 
    		 */
    		System.out.println(g.getTimeZone());
    		//得到太平洋所支持的标准时间GMT-08:00的ids
    		String[] ids = TimeZone.getAvailableIDs(-8 * 60 * 60 * 1000);
    		//如果数组为空，则说明不存在对应的ids
    		if (ids.length == 0) {
    			System.out.println("不存在对应的ids");
    		}
    		System.out.println("current time");
    		//创建一个太平洋标准时间时区
    		SimpleTimeZone pdt = new SimpleTimeZone(-8 * 60 * 60 * 1000, ids[0]);
    		pdt.setStartRule(Calendar.APRIL, 1, Calendar.SUNDAY, 2 * 60 * 60 * 1000);
    		pdt.setEndRule(Calendar.OCTOBER, -1, Calendar.SUNDAY, 2 * 60 * 60 * 1000);
    		//创建一个与太平洋夏令时区域的GregorianCalendar ,设置当前的日期和时间
    		Calendar calendar = new GregorianCalendar(pdt);
    		Date trialTime = new Date();
    		calendar.setTime(trialTime);
    		
    		 //输出一些信息
    		 System.out.println("ERA: " + calendar.get(Calendar.ERA));
    		 System.out.println("YEAR: " + calendar.get(Calendar.YEAR));
    		 System.out.println("MONTH: " + calendar.get(Calendar.MONTH));
    		 System.out.println("WEEK_OF_YEAR: " + calendar.get(Calendar.WEEK_OF_YEAR));
    		 System.out.println("WEEK_OF_MONTH: " + calendar.get(Calendar.WEEK_OF_MONTH));
    		 System.out.println("DATE: " + calendar.get(Calendar.DATE));
    		 System.out.println("DAY_OF_MONTH: " + calendar.get(Calendar.DAY_OF_MONTH));
    		 System.out.println("DAY_OF_YEAR: " + calendar.get(Calendar.DAY_OF_YEAR));
    		 System.out.println("DAY_OF_WEEK: " + calendar.get(Calendar.DAY_OF_WEEK));
    		 System.out.println("DAY_OF_WEEK_IN_MONTH: "
    		                    + calendar.get(Calendar.DAY_OF_WEEK_IN_MONTH));
    		 System.out.println("AM_PM: " + calendar.get(Calendar.AM_PM));
    		 System.out.println("HOUR: " + calendar.get(Calendar.HOUR));
    		 System.out.println("HOUR_OF_DAY: " + calendar.get(Calendar.HOUR_OF_DAY));
    		 System.out.println("MINUTE: " + calendar.get(Calendar.MINUTE));
    		 System.out.println("SECOND: " + calendar.get(Calendar.SECOND));
    		 System.out.println("MILLISECOND: " + calendar.get(Calendar.MILLISECOND));
    		 System.out.println("ZONE_OFFSET: "
    		                    + (calendar.get(Calendar.ZONE_OFFSET)/(60*60*1000)));
    		 System.out.println("DST_OFFSET: "
    		                    + (calendar.get(Calendar.DST_OFFSET)/(60*60*1000)));
    	
    		 System.out.println("Current Time, with hour reset to 3");
    		 calendar.clear(Calendar.HOUR_OF_DAY); // 没有被重写
    		 calendar.set(Calendar.HOUR, 3);
    		 System.out.println("ERA: " + calendar.get(Calendar.ERA));
    		 System.out.println("YEAR: " + calendar.get(Calendar.YEAR));
    		 System.out.println("MONTH: " + calendar.get(Calendar.MONTH));
    		 System.out.println("WEEK_OF_YEAR: " + calendar.get(Calendar.WEEK_OF_YEAR));
    		 System.out.println("WEEK_OF_MONTH: " + calendar.get(Calendar.WEEK_OF_MONTH));
    		 System.out.println("DATE: " + calendar.get(Calendar.DATE));
    		 System.out.println("DAY_OF_MONTH: " + calendar.get(Calendar.DAY_OF_MONTH));
    		 System.out.println("DAY_OF_YEAR: " + calendar.get(Calendar.DAY_OF_YEAR));
    		 System.out.println("DAY_OF_WEEK: " + calendar.get(Calendar.DAY_OF_WEEK));
    		 System.out.println("DAY_OF_WEEK_IN_MONTH: "
    		                    + calendar.get(Calendar.DAY_OF_WEEK_IN_MONTH));
    		 System.out.println("AM_PM: " + calendar.get(Calendar.AM_PM));
    		 System.out.println("HOUR: " + calendar.get(Calendar.HOUR));
    		 System.out.println("HOUR_OF_DAY: " + calendar.get(Calendar.HOUR_OF_DAY));
    		 System.out.println("MINUTE: " + calendar.get(Calendar.MINUTE));
    		 System.out.println("SECOND: " + calendar.get(Calendar.SECOND));
    		 System.out.println("MILLISECOND: " + calendar.get(Calendar.MILLISECOND));
    		 System.out.println("ZONE_OFFSET: "
    		        + (calendar.get(Calendar.ZONE_OFFSET)/(60*60*1000))); // 小时
    		 System.out.println("DST_OFFSET: "
    		        + (calendar.get(Calendar.DST_OFFSET)/(60*60*1000))); // 小时
    	}
    
    }

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[SouthEast]: /images/20220610/640e872ed2774a9080fcb77eb403f129.png
[SouthEast 1]: /images/20220610/9f29091a1959494aa1d03e6e1a6fb659.png
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