Question

I am trying to make a constructor that takes a string and constructs a date object. This is my solution so far but I am getting this error:

Constructor call must be the first statement in a constructor

private int m;
private int d;
private int y;
private String[] dateStrings;

public Date(int month, int day, int year) {
          m = month;
          d = day;
          y = year;  
  }

public Date(String s) {
      dateStrings = s.split("/");
      this(Integer.parseInt(dateStrings[0]), Integer.parseInt(dateStrings[1]), Integer.parseInt(dateStrings[2]));
  }

I realize I need this(...) before everything but how can I do that when I need to populate dateStrings first?
How can I avoid this error?
Note: to construct a date with a string it is in the format of “month/day/year”

Answer 1

this() needs to be called first.

Instead move the assignment to a private method.

private void assginValues (int month, int day, int year){
          m = month;
          d = day;
          y = year;  
}

If you also need dateStrings populated, you can build it in this method too.

Then call the method from both constructors. Make sure that the constructor accepting a String does not call this() since the shared method takes care of assigning the values.

You can also do everything in one line, but then you call split() multiple times which is wasteful:

this(Integer.parseInt(s.split("/")[0]), Integer.parseInt(s.split("/")[1]), Integer.parseInt(s.split("/")[2]));