java 获取当前年份 月份,当月第一天和最后一天

java 获取当前年份、月份以及当月第一天和最后一天：

package com.bsoft.test;

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

public class CalendarTest {
	public static void main(String[] args) {
		//1、 获取当前年份、月份、日期
		Calendar cale = null;
		cale = Calendar.getInstance();
		int year = cale.get(Calendar.YEAR);
		int month = cale.get(Calendar.MONTH) + 1;
		int day = cale.get(Calendar.DATE);
		int hour = cale.get(Calendar.HOUR_OF_DAY);
		int minute = cale.get(Calendar.MINUTE);
		int second = cale.get(Calendar.SECOND);
		int dow = cale.get(Calendar.DAY_OF_WEEK);
		int dom = cale.get(Calendar.DAY_OF_MONTH);
		int doy = cale.get(Calendar.DAY_OF_YEAR);

		System.out.println("Current Date: " + cale.getTime());
		System.out.println("Year: " + year);
		System.out.println("Month: " + month);
		System.out.println("Day: " + day);
		System.out.println("Hour: " + hour);
		System.out.println("Minute: " + minute);
		System.out.println("Second: " + second);
		System.out.println("Day of Week: " + dow);
		System.out.println("Day of Month: " + dom);
		System.out.println("Day of Year: " + doy);

		// 2、获取前月第一天和最后一天
		SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd");
		String firstday, lastday;
		// 获取前月的第一天
		cale = Calendar.getInstance();
		cale.add(Calendar.MONTH, 0);
		cale.set(Calendar.DAY_OF_MONTH, 1);
		firstday = format.format(cale.getTime());
		// 获取前月的最后一天
		cale = Calendar.getInstance();
		cale.add(Calendar.MONTH, 1);
		cale.set(Calendar.DAY_OF_MONTH, 0);
		lastday = format.format(cale.getTime());
		System.out.println("前月第一天和最后一天分别是 ： " + firstday + " and " + lastday);

		// 获取当前日期字符串
		Date d = new Date();
		System.out.println("当前日期字符串1：" + format.format(d));
		System.out.println("当前日期字符串2：" + year + "/" + month + "/" + day + " "
				+ hour + ":" + minute + ":" + second);

                //3、获取指定年月份的第一天和最后一天
                  int year = 2014;
		  int month = 5;
		  Calendar cal = Calendar.getInstance();
		  // 不加下面2行，就是取当前时间前一个月的第一天及最后一天
		  cal.set(Calendar.YEAR,year);
		  cal.set(Calendar.MONTH, month);
		  cal.set(Calendar.DAY_OF_MONTH, 1);
		  cal.add(Calendar.DAY_OF_MONTH, -1);
		  Date lastDate = cal.getTime();
		  System.out.println(format.format(lastDate));
		  
		  cal.set(Calendar.DAY_OF_MONTH, 1);
		  Date firstDate = cal.getTime();
		  System.out.println(format.format(firstDate));
	}

}