Thread: Time class - previousSecond()

im unable to work out my previousSecond() in Time class.

here is my code:

 
	}void setHour(int hour){
		if (hour >= 0 && hour <= 23){
			this.hour = hour; 
		}else{ 
			throw new IllegalArgumentException("Invalid hour!");
		}
 
	}void setMinute(int minute){
			if (minute >= 0 && minute <= 59){
				this.minute = minute; 
			}else {
				throw new IllegalArgumentException("Invalid minute!");
			}
 
	}void setSecond(int second){
		if (second >= 0 && second <= 59){
			this.second = second;
		}else{ 
			throw new IllegalArgumentException("Invalid second!");
		}
 
 
	}public Time previousSecond(){
			second--; 
			if (second == 60){
				second = 0;
				minute--; 	
 
			}if (minute == 60){
				minute = 0;
				hour--; 	
 
			}if (hour == 24){
				hour = 0; 
			}
			return this; 
	}
 
}

this is the test code:

      // Test previousSecond()
      t1.setTime(0, 0, 2);
      System.out.println(t1.previousSecond());
      System.out.println(t1.previousSecond().previousSecond());

result i get is 00:00:-1 instead of 23:59:59. whats wrong with my code?