compare Two variables of enum in java

Question

public enum Direction {
 UP,
 RIGHT,
 DOWN,
 LEFT,
}

i have two enum variables (a and b), in one case i have to check, if b is the next of a for example if a=UP and b=RIGHT. and also if a=left and b=UP. mabe something like this:

if(Direction.valueOf(a+1)==Direction.valueOf(b))

but when a=LEFT it would be out of bounds like an array right ?

• 0xff: yes, you'd need to manually wrap around
• Jack: honestly I would not bother valueOf(). Just check their ordinal() with %

Answer 1

Try this.

public enum Direction {
 UP,
 RIGHT,
 DOWN,
 LEFT;
 
 private static final Direction[] VALUES = values();
 
 public Direction next() {
 return VALUES[(ordinal() + 1) % VALUES.length];
 }
 }
public static void main(String[] args) {
 Direction a = Direction.LEFT;
 Direction b = Direction.UP;
 System.out.println(a.next() == b);
}

output:

true

Answer 2

if (b == Direction.values()[(a.ordinal() + 1) % Direction.values().length])

• Neeraj: Your answer could be improved with additional supporting information. Please edit to add further details, such as citations or documentation, so that others can confirm that your answer is correct. You can find more information on how to write good answers in the help center.