处理java日期的一些操作

川长思鸟来 2022-07-14 04:58 129阅读 0赞

package yyf.java.util.DateTest;
    
    import java.text.DateFormat;
    import java.text.SimpleDateFormat;
    import java.util.Calendar;
    import java.util.Date;
    
    import org.junit.Test;
    
    /**
     * 对日期类的一些操作
     * 
     * @author Yu Yufeng
     *
     */
    public class DateUse {
    	@Test
    	public void test() {
    		System.out.println("DateUse.test()");
    	}
    	
    	/**
    	 * 日期格式
    	 */
    	@Test
    	public void testFormate() {
    		Date date = new Date();
    		DateFormat f = new SimpleDateFormat("yyyy-MM-dd");
    		String dateStr = f.format(date);
    		System.out.println(dateStr);
    	}
    
    	/**
    	 * 对时间的加减
    	 */
    	@Test
    	public void testDateModify() {
    		Date date = new Date();
    		Calendar cNow = Calendar.getInstance();
    		cNow.setTime(date);
    		System.out.println(cNow);
    		cNow.add(Calendar.DATE, -1);
    		Date now = cNow.getTime();
    		System.out.println(now);
    
    	}
    
    	/**
    	 * 得到一天的时间 0~24
    	 */
    	@Test
    	public void testGetOneDay() {
    		Date date = new Date();//当前一天
    		Date res;
    		Calendar cNow = Calendar.getInstance();
    		cNow.setTime(date);
    		res = cNow.getTime();
    		cNow.set(Calendar.HOUR_OF_DAY, 0);
    		cNow.set(Calendar.SECOND, 0);
    		cNow.set(Calendar.MINUTE, 0);
    		cNow.set(Calendar.MILLISECOND, 0);
    		res = cNow.getTime();
    		System.out.println(res);
    		cNow.add(Calendar.DATE, -1);
    		res = cNow.getTime();
    		System.out.println(res);
    
    	}/**
    	 * 得到一天之前七天
    	 */
    	@Test
    	public void testGet7DaysBefore() {
    		Date date = new Date();//当前一天
    		Date res;
    		Calendar cNow = Calendar.getInstance();
    		cNow.setTime(date);
    		res = cNow.getTime();
    		cNow.set(Calendar.HOUR_OF_DAY, 0);
    		cNow.set(Calendar.SECOND, 0);
    		cNow.set(Calendar.MINUTE, 0);
    		cNow.set(Calendar.MILLISECOND, 0);
    		res = cNow.getTime();
    		for(int i=0;i<7;i++){
    			cNow.add(Calendar.DATE, -1);
    			res = cNow.getTime();
    			System.out.println(res);
    		}
    		
    
    	}
    }

代码： [https://github.com/yyfyyf1994/knowledge/blob/master/src/yyf/java/util/DateTest/DateUse.java][https_github.com_yyfyyf1994_knowledge_blob_master_src_yyf_java_util_DateTest_DateUse.java]

[https_github.com_yyfyyf1994_knowledge_blob_master_src_yyf_java_util_DateTest_DateUse.java]: https://github.com/yyfyyf1994/knowledge/blob/master/src/yyf/java/util/DateTest/DateUse.java