Question

我需要对以下数组进行排序：

String [][] myArray = {{"John", "3", "10"}, {"Paul", "16","2"}, 
                       {"Mike","8","20"},    {"Peter","5","0"}};

进入以下数组：

String [][] myArray = {{"John", "3", "10"}, {"Mike","8","20"}, 
                       {"Paul", "16","2"}, {"Peter","5","0"}};

我有两节课。第一个包含数组，另一个实现Comparator接口。这是MyArray类：

public class MyArray {
public static void main(String[] args) {
String [][] myArray = {{"John", "3", "10"}, {"Paul", "16","2"}, 
                       {"Mike","8","20"},{"Peter","5","0"}};
ByName byName = new ByName();
Arrays.sort(myArray,byName);
}
}

这是ByName类：

  import java.util.Comparator;
    public class ByName implements Comparator {
         public int compare(Object o1, Object o2) {
            String name1 = (String)((MyArray) o1)[0]);
            String name2 = (String)((MyArray) o2)[0]);
    return (name1>name2) ? 1 : -1;
// Here I am confused, how can I compare it, how can I sort my array 
// alphabetically by the first element of each element, i.e. by the names. 
            }
    }

Answer 1

你几乎得到了它：而不是

中的<

return (name1>name2) ? 1 : -1;

使用compareTo()：

String name1 = ((String[])o1)[0];
String name2 = ((String[])o2)[0];
return name1.compareTo(name2);

Answer 2

您还可以使用类的对象而不是二维数组：

import java.util.Comparator;
    public class ByName implements Comparator {
         public int compare(Object o1, Object o2) {
            String name1 = (String)(( o1));
            String name2 = (String)((o2));
    return (name1>name2) ? 1 : -1;

如何使用`Comparator`接口对二维数组进行排序？

2 个答案: