无限循环。有人有主意吗？

public int sum (int num1, int num2){
    int sum = 0;
        if(num2>num1){
        for (int i = num1; i<=num2; i++){
            sum = sum + i;
            }
        }
        else{
        for (int i = num2; i <= num1; i++){
            sum = sum + i;
            }
        }
    System.out.println("The sum between " +num1+ " and " +num2+ " equals " + sum);
    return sum(num1, num2);
    }
}
public int sum (int num1, int num2){
    int su