Class vs. instance fields

• static field

  • System.out.println(Time.AM);
  • Time is a class; AM is a class field

• instance field

  • Time t=new Time();
  • t.sec=37;
  • t is an instance of Time, an object of type Time
  • sec is field of this instance
  • Time s=new Time(); s.sec=52; // another instance!
  • System.out.println(t.AM); // also valid

class Time {

static string AMString = "AM";

int hour, min, sec;

...

}

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