Java更改矩阵2D中的行索引

Question

I try to create a matrix in java that stores a data sets. I want to construct a matrix of 2D, where the row presents the days of year , and columns presents the hours of day. This is my matrix :

int [][] dataset = new int [366] [27] ; 

I want to make the rows indexed using MyLocalDate.hashcode() instead of int 0 , 1 ... 365 However, I want to access to my specific data into matrix for example:

int data  = dataset [ MyLocalDate.hashcode() ][ 10 ] ; 

Answer 1

Check this code out...it will show the current day number.

Eg: 20 March 2018 --> Day of the year 79.

21 March 2018 --> Day of the year 80.

with this i hope you can get a idea how to tackle your problem.

import java.util.Calendar;
import java.util.Date;
import java.util.TimeZone;

public class DayOfYear 
{
    public static void main(String args[])
    {
       Calendar localCalendar = Calendar.getInstance(TimeZone.getDefault());
       int CurrentDayOfYear = localCalendar.get(Calendar.DAY_OF_YEAR);
       System.out.println("Day of Year: " + CurrentDayOfYear);
       Calendar gmtCalendar = 
       Calendar.getInstance(TimeZone.getTimeZone("GMT"));
    }
}

edit: it seems there are far better ways to do this in java 8. check this link