java基础——时间操作

梦里梦外; 2023-06-27 11:29 15阅读 0赞

package date;
    
    import java.text.ParseException;
    import java.text.SimpleDateFormat;
    import java.util.Date;
    
    public class TestDate { 
    
        public static void main(String[] args){ 
    		//根据时间进行升序排序
            int yearStart = 1970;
            int yearEnd = 2000;
    
            Date[] ds = new Date[9];
    
            for(int i=0;i<ds.length;i++){ 
                ds[i] = randomDate(yearStart,yearEnd);
            }
            System.out.println("得到的随机数组：");
            for(int i=0;i<ds.length;i++){ 
                System.out.print(toString(ds[i])+" | ");
                if((i+1)%3==0){ 
                    System.out.println();
                }
            }
    
            //选择排序
            for(int j=0;j<ds.length-1;j++){ 
                for(int i=j+1;i<ds.length;i++){ 
                    String strTimeI = toString(ds[i],"HHmmss");
                    String strTimeJ = toString(ds[j],"HHmmss");
    
                    int ITimeI = Integer.parseInt(strTimeI);
                    int ITimeJ = Integer.parseInt(strTimeJ);
    
                    if(ITimeI<ITimeJ){ 
                        Date temp= ds[j];
                        ds[j] = ds[i];
                        ds[i] = temp;
                    }
                }
            }
    
            System.out.println("排序后的数组：");
            for(int i=0;i<ds.length;i++){ 
    
                System.out.print(toString(ds[i])+" | ");
                if((i+1)%3==0){ 
                    System.out.println();
                }
            }
        }
    
        public static String toString(Date d){ 
            return toString(d,"yyyy-MM-dd HH:mm:ss");
        }
    
        public static String toString(Date d,String format){ 
            SimpleDateFormat sdf = new SimpleDateFormat(format);
            return sdf.format(d);
        }
    
        private static Date randomDate(int yearStart,int yearEnd){ 
           SimpleDateFormat sdf = new SimpleDateFormat("yyyyy");
            try { 
                Date dstart = sdf.parse(String.valueOf(yearStart));
                Date dend = sdf.parse(String.valueOf(yearEnd+1));
    
                long timeStart = dstart.getTime();
                long timeEnd = dend.getTime()-1;
                long timeRandom = (long)((timeStart-timeEnd)*Math.random()+timeStart);
    
                return new Date(timeRandom);
    
            } catch (ParseException e) { 
                e.printStackTrace();
            }
            return null;
        }
    }
    
    ```