如何在Java中以微秒精度测量时间？

public class MicrosecondTimer {
    public static void main(String[] args) {
        long start = System.nanoTime();
        // 要执行的代码
        long end = System.nanoTime();
        long duration = end - start;
        long microseconds = duration / 1000;

        System.out.println("执行代码花费了 " + microseconds + " 微秒。");
    }
}