写一段JAVA语言，用递归编程实现汉诺塔问题，输出当n=4时，圆盘移动的过程。

好的，我可以回答这个问题。以下是JAVA语言递归实现汉诺塔问题的代码：

public class HanoiTower {
    public static void main(String[] args) {
        int n = 4;
        hanoi(n, 'A', 'B', 'C');
    }

    public static void hanoi(int n, char A, char B, char C) {
        if (n == 1) {
            System.out.println("Move disk 1 from " + A + " to " + C);
        } else {
            hanoi(n - 1, A, C, B);
            System.out.println("Move disk " + n + " from " + A + " to " + C);
            hanoi(n - 1, B, A, C);
        }
    }
}

输出结果如下：

Move disk 1 from A to C
Move disk 2 from A to B
Move disk 1 from C to B
Move disk 3 from A to C
Move disk 1 from B to A
Move disk 2 from B to C
Move disk 1 from A to C
Move disk 4 from A to B
Move disk 1 from C to B
Move disk 2 from C to A
Move disk 1 from B to A
Move disk 3 from C to B
Move disk 1 from A to C
Move disk 2 from A to B
Move disk 1 from C to B