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如何使用Comparator接口对二维数组进行排序?

[英]How to sort a two dimensional array using `Comparator` interface?

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"}}; 

放入以下数组:

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. 
            }
    }

您几乎明白了:而不是< in

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

使用compareTo()

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

您还可以使用类的对象代替二维数组:

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;

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