Question

我的代码用于对员工列表进行排序，首先按部门排序（第一列），然后按年龄（第三列）按升序排序。我搜索了几个小时无济于事。到目前为止我的代码：

    public class Company
    {
    public static void main(String[] args)
    {
        String[][] departmentList = new String[13][3];
            departmentList[0][0] = "Accounting";
            departmentList[0][1] = "Counting Guru";
            departmentList[0][2] = "55";
            departmentList[1][0] = "Accounting";
            departmentList[1][1] = "Counting Pro";
            departmentList[1][2] = "45";
            departmentList[2][0] = "Accounting";
            departmentList[2][1] = "Counting Savvy";
            departmentList[2][2] = "40";
            departmentList[3][0] = "Accounting";
            departmentList[3][1] = "Counting Novice";
            departmentList[3][2] = "25";
            departmentList[4][0] = "Marketing";
            departmentList[4][1] = "Sales Guru";
            departmentList[4][2] = "50";
            departmentList[5][0] = "Marketing";
            departmentList[5][1] = "Sales Pro";
            departmentList[5][2] = "48";
            departmentList[6][0] = "Marketing";
            departmentList[6][1] = "Sales Savvy";
            departmentList[6][2] = "38";
            departmentList[7][0] = "Human Resources";
            departmentList[7][1] = "Hiring Guru";
            departmentList[7][2] = "58";
            departmentList[8][0] = "Human Resources";
            departmentList[8][1] = "Hiring Pro";
            departmentList[8][2] = "47";
            departmentList[9][0] = "Information Systems";
            departmentList[9][1] = "Hacking Pro";
            departmentList[9][2] = "46";
            departmentList[10][0] = "Information Systems";
            departmentList[10][1] = "Hacking Guru";
            departmentList[10][2] = "51";
            departmentList[11][0] = "Information Systems";
            departmentList[11][1] = "Hacking Savvy";
            departmentList[11][2] = "38";
            departmentList[12][0] = "Information Systems";
            departmentList[12][1] = "Hacking Novice";
            departmentList[12][2] = "23";

        for(int row = 0; row < departmentList.length; row++)
        {
            System.out.println(departmentList[row][0] + "\t" + departmentList[row][1] + "\t" + departmentList[row][2]);
        }
    }
}

我希望输出根据部门打印列表，然后根据年龄，最小到最旧。任何帮助表示赞赏。

Answer 1

您可以使用Arrays.sort并提供自定义比较器：

Arrays.sort(departmentList, new Comparator<String[]>() {
        @Override
        public int compare(String[] o1, String[] o2) {
           int cmp =  o1[0].compareTo(o2[0]);
           return cmp != 0 ? cmp : o1[2].compareTo(o2[2]);
        }           
    });

实际上，更好的方法是创建自己的Employee类，并让它实现类似的界面。

输出：

Accounting  Counting Novice 25
Accounting  Counting Savvy  40
Accounting  Counting Pro    45
Accounting  Counting Guru   55
Human Resources Hiring Pro  47
Human Resources Hiring Guru 58
Information Systems Hacking Novice  23
Information Systems Hacking Savvy   38
Information Systems Hacking Pro 46
Information Systems Hacking Guru    51
Marketing   Sales Savvy 38
Marketing   Sales Pro   48
Marketing   Sales Guru  50

Answer 2

这样做

您的Comparator

class SimpleComparator implements Comparator<String[]> {
    @Override
    public int compare(String[] o1, String o2[]) {       
        if(!o1[0].equalsIgnoreCase(o2[0])){
            return o1[0].compareToIgnoreCase(o2[0]);
        }
        int value1 = Integer.parseInt(o1[2]);
        int value2 = Integer.parseInt(o2[2]);
        if(value1!=value2){
            return new Integer(value1).compareTo(value2);
        }
        return 0;
    }
}

您的排序

 Arrays.sort(departmentList,new SimpleComparator());
 for(int row = 0; row < departmentList.length; row++)
 {
      System.out.println(departmentList[row][0] + "\t" + departmentList[row][1] + "\t" + departmentList[row][2]);
 }

<强>输出

Accounting  Counting Novice 25
Accounting  Counting Savvy  40
Accounting  Counting Pro    45
Accounting  Counting Guru   55
Human Resources Hiring Pro  47
Human Resources Hiring Guru 58
Information Systems Hacking Novice  23
Information Systems Hacking Savvy   38
Information Systems Hacking Pro 46
Information Systems Hacking Guru    51
Marketing   Sales Savvy 38
Marketing   Sales Pro   48
Marketing   Sales Guru  50

如何通过java中的第3列按升序对2D数组进行排序？

2 个答案: