java - 比较器如何在内部工作？

Question

这对你来说可能听起来微不足道，但我很难想象比较器/array.sort。我们如何仅使用 2 个参数对完整数组进行排序？它在内部是如何工作的？

例如- Input -[5,3,2,6,8,10,1], Output- [1,2,3,5,6,8,10] 它在内部使用哪种算法？它首先比较哪两个对象？（5 比 3？）然后接下来的两个对象是什么？（5 比 2？）还是（3 比 2）？

public static void main(String[] args) {
         Integer[] tring = new Integer[]{5,3,2,6,8,10,1};
       lol(tring);
       for(int i=0;i<tring.length;i++){
       System.out.println(tring[i]);
       }
    }
    
    public static void lol(Integer[] args) {
      Arrays.sort(args,(h1,h2)->h1-h2);
    }

标签： javasortingcomparator

Answer 1

您可以像这样可视化该过程。

Integer[] tring = new Integer[]  {5, 3, 2, 6, 8, 10, 1};
Comparator<Integer> comparator = (a, b) -> {
    System.out.println(Arrays.toString(tring) + " comparing " + a + " and " + b);
    return a.compareTo(b);
};
Arrays.sort(tring, comparator);
System.out.println(Arrays.toString(tring));

结果：

[5, 3, 2, 6, 8, 10, 1] comparing 3 and 5
[5, 3, 2, 6, 8, 10, 1] comparing 2 and 3
[5, 3, 2, 6, 8, 10, 1] comparing 6 and 2
[2, 3, 5, 6, 8, 10, 1] comparing 6 and 3
[2, 3, 5, 6, 8, 10, 1] comparing 6 and 5
[2, 3, 5, 6, 8, 10, 1] comparing 8 and 5
[2, 3, 5, 6, 8, 10, 1] comparing 8 and 6
[2, 3, 5, 6, 8, 10, 1] comparing 10 and 5
[2, 3, 5, 6, 8, 10, 1] comparing 10 and 8
[2, 3, 5, 6, 8, 10, 1] comparing 1 and 6
[2, 3, 5, 6, 8, 10, 1] comparing 1 and 3
[2, 3, 5, 6, 8, 10, 1] comparing 1 and 2
[1, 2, 3, 5, 6, 8, 10]