java 计算两个日期之间天数

 

import java.text.ParseException;
import java.text.SimpleDateFormat;


/**
 * @author JavaAlpha
 * @date 2011-8-23
 * @version V 1.0
 */

public class TT {

	/**
	 * @param args
	 */
	public static void main(String[] args) {
		SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd");
	    long to = 0;
		try {
			to = df.parse("2011-4-15").getTime();
		} catch (ParseException e) {
			e.printStackTrace();
		}
	    long from = 0;
		try {
			from = df.parse("2011-8-20").getTime();
		} catch (ParseException e) {
			e.printStackTrace();
		}
	    System.out.println((from - to) / (1000 * 60 * 60 * 24));
	}

}