java 获取当前年份 月份,当月第一天和最后一天

/** * 项目名称：dream_user * 项目包名：org.fore.integration.service.impl * 创建时间：2017年12月1日上午11:41:52 * 创建者：Administrator * 创建地点： */package org.fore.integration.service.impl;import java.text.SimpleDateFormat;import java.util.Calendar;import java.util.Date;/** * 描述： * @author songfayuan * 2017年12月1日上午11:41:52 */public class test {/** * 描述： * @param args * @author songfayuan * 2017年12月1日上午11:41:52 */public static void main(String[] args) {// 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);            // 获取当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("本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);  }}