基于多个参数的Java数组排序

Question

我有一个数组，我想按升序对其进行排序。但是，我想引用 boolean 数组对它们进行排序。我想按升序对 true 的值进行排序，然后对 false 的值进行排序升序。很少有人纠结于如何到达那里。

这是我目前拥有的:

Object[] arr = new Object[6];

arr[0] = new Object(2); 
arr[1] = new Object(5); 
arr[2] = new Object(3); 
arr[3] = new Object(1);
arr[4] = new Object(6);
arr[5] = new Object(4);

Available[] avalarr = new Available[6];

availarr[0] = new Available (true);
availarr[1] = new Available (false);
availarr[2] = new Available (false);
availarr[3] = new Available (true);
availarr[4] = new Available (true);
availarr[5] = new Available (false);

我需要的输出是:

1 2 6 3 4 5

Answer 1

代码:

import java.util.Arrays;

public class SelectiveSort {

    public static void main(String[] args) {

        Item [] items = new Item [6];
        items[0] = new Item(2, true);
        items[1] = new Item(5, false);
        items[2] = new Item(3, false);
        items[3] = new Item(1, true);
        items[4] = new Item(6, true);
        items[5] = new Item(4, false);

        System.out.println("Before Sorting:");
        // Removed enhanced for loop
        for(int i = 0; i < items.length; i++) {
            System.out.print(items[i].getIntValue() + " ");
        }

        // Sorting
        Arrays.sort(items);

        System.out.println("\n\nAfter Sorting:");
        // Removed enhanced for loop
        for(int i = 0; i < items.length; i++) {
            System.out.print(items[i].getIntValue() + " ");
        }
        System.out.println();
    }
}

class Item implements Comparable<Item> {

    private int _intValue;
    private boolean _boolValue;

    public Item(int intValue, boolean boolValue) {
        _intValue = intValue;
        _boolValue = boolValue;
    }

    public int getIntValue() { return _intValue; }

    public boolean getBoolValue() { return _boolValue; }

    @Override
    public int compareTo(Item otherItem) {

        // Using explicit comparison
        int boolComparison = (_boolValue == otherItem._boolValue) ? 0 :
            (_boolValue) ? 1 : -1;
        return (boolComparison != 0) ? -boolComparison :
            ( (_intValue == otherItem.getIntValue()) ? 0 :
                (_intValue > otherItem.getIntValue()) ? 1 : -1);
    }
}

输出:

排序前:2 5 3 1 6 4

排序后:1 2 6 3 4 5

解释:

想法是让您的“Item”实现Comparable，并根据所需的顺序覆盖compareTo(Item otherItem) 函数。
完成后，您需要做的就是对 Item 数组调用 Arrays.sort()。

版本 2(没有 Comparable/Comparator):

public class SelectiveSort {

    public static void main(String[] args) {

        Item [] items = new Item [6];
        items[0] = new Item(2, true);
        items[1] = new Item(5, false);
        items[2] = new Item(3, false);
        items[3] = new Item(1, true);
        items[4] = new Item(6, true);
        items[5] = new Item(4, false);

        System.out.println("Before Sorting:");
        for(int i = 0; i < items.length; i++) {
            System.out.print(items[i].getIntValue() + " ");
        }

        // Sorting
        bubbleSort(items);

        System.out.println("\n\nAfter Sorting:");
        for(int i = 0; i < items.length; i++) {
            System.out.print(items[i].getIntValue() + " ");
        }
        System.out.println();
    }

    public static void bubbleSort(Item [] items) {
        int n = items.length;
        do {
            int newN = 0;
            for(int i = 1; i < n; i++) {
                if(compareTo(items[i-1], items[i]) == 1) {
                    Item temp = items[i-1];
                    items[i-1] = items[i];
                    items[i] = temp;

                    newN = i;
                }
            }
            n = newN;
        } while (n != 0);
    }

    public static int compareTo(Item item1, Item item2) {

        int boolComparison = (item1.getBoolValue() == item2.getBoolValue())
                ? 0 : (item1.getBoolValue()) ? 1 : -1;
        return (boolComparison != 0) ? -boolComparison :
            ( (item1.getIntValue() == item2.getIntValue()) ? 0 :
                (item1.getIntValue() > item2.getIntValue()) ? 1 : -1);
    }
}