Java获取某年某月第一天/最后一天 Java实现获取某年某月第一天/最后一天的方法

/**
 * @Title:FisrtDayOfMonth.java
 * @Package:com.you.freemarker.model
 * @Description:获取某年某月的第一天
 * @author:Youhaidong(游海东)
 * @version V1.0
 */
package com.you.freemarker.model;
import java.text.SimpleDateFormat;
import java.util.Calendar;
/**
 * 类功能说明
 * 类修改者 修改日期
 * 修改说明
 * <p>Title:FisrtDayOfMonth.java</p>
 * <p>Description:游海东个人开发</p>
 * <p>Copyright:Copyright(c)2013</p>
 * @author:游海东
 * @version V1.0
 */
public class FisrtDayOfMonth
{
  /**
   * 获取某年某月的第一天
   * @Title:getFisrtDayOfMonth
   * @Description:
   * @param:@param year
   * @param:@param month
   * @param:@return
   * @return:String
   * @throws
   */
  public static String getFisrtDayOfMonth(int year,int month)
  {
    Calendar cal = Calendar.getInstance();
    //设置年份
    cal.set(Calendar.YEAR,year);
    //设置月份
    cal.set(Calendar.MONTH, month-1);
    //获取某月最小天数
    int firstDay = cal.getActualMinimum(Calendar.DAY_OF_MONTH);
    //设置日历中月份的最小天数
    cal.set(Calendar.DAY_OF_MONTH, firstDay);
    //格式化日期
    SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
    String firstDayOfMonth = sdf.format(cal.getTime());
    return firstDayOfMonth;
  }
  /**
   * @Title:main
   * @Description:
   * @param:@param args
   * @return: void
   * @throws
   */
  public static void main(String[] args)
  {
    String firstDay = getFisrtDayOfMonth(2014,5);
    System.out.println("测试结果：");
    System.out.println("获取当前月的第一天：" + firstDay);
  }
}

/**
 * @Title:LastDayOfMonth.java
 * @Package:com.you.freemarker.model
 * @Description:获取某月的最后一天
 * @author:Youhaidong(游海东)
 * @date:2014-5-29 下午10:58:20
 * @version V1.0
 */
package com.you.freemarker.model;
import java.text.SimpleDateFormat;
import java.util.Calendar;
/**
 * 类功能说明
 * 类修改者 修改日期
 * 修改说明
 * <p>Title:LastDayOfMonth.java</p>
 * <p>Description:游海东个人开发</p>
 * <p>Copyright:Copyright(c)2013</p>
 * @author:游海东
 * @version V1.0
 */
public class LastDayOfMonth
{
  /**
   * 获取某月的最后一天
   * @Title:getLastDayOfMonth
   * @Description:
   * @param:@param year
   * @param:@param month
   * @param:@return
   * @return:String
   * @throws
   */
  public static String getLastDayOfMonth(int year,int month)
  {
    Calendar cal = Calendar.getInstance();
    //设置年份
    cal.set(Calendar.YEAR,year);
    //设置月份
    cal.set(Calendar.MONTH, month-1);
    //获取某月最大天数
    int lastDay = cal.getActualMaximum(Calendar.DAY_OF_MONTH);
    //设置日历中月份的最大天数
    cal.set(Calendar.DAY_OF_MONTH, lastDay);
    //格式化日期
    SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
    String lastDayOfMonth = sdf.format(cal.getTime());
    return lastDayOfMonth;
  }
  /**
   * @Title:main
   * @Description:
   * @param:@param args
   * @return: void
   * @throws
   */
  public static void main(String[] args)
  {
    String lastDay = getLastDayOfMonth(2014,5);
    System.out.println("测试结果：");
    System.out.println("获取当前月的最后一天：" + lastDay);
  }
}