二维数组排序实例

import java.util.*;
public class Main {
public static void main(String[] args) {
  String[][] arr = {{"B","啊","20%"},
  {"C","中","12%"},
  {"A","我","55%"}} ;
  //缺省(按0列升序)
  Arrays.sort(arr, new TwoDimArrayComparator());
  printArray(arr);
  //按0列降序
  Arrays.sort(arr, new TwoDimArrayComparator(0,-1));
  printArray(arr);
  //按1列升序
  Arrays.sort(arr, new TwoDimArrayComparator(1));
  printArray(arr);
  //按1列降序
  Arrays.sort(arr, new TwoDimArrayComparator(1,-1));
  printArray(arr);
  //按2列升序
  Arrays.sort(arr, new TwoDimArrayComparator(2));
  printArray(arr);
  //按2列降序
  Arrays.sort(arr, new TwoDimArrayComparator(2,-1));
  printArray(arr);
  }
  public static void printArray(String[][] arr) {
     for (int i= 0; i< arr.length ; i++) {
     for (int j = 0; j < arr[i].length; j++) {
     System.out.print(arr[i][j] +"\t");
  }
  System.out.println();
}
System.out.println("======================");
}
}

class TwoDimArrayComparator implements Comparator{
   private int keyColumn = 0;
   private int sortOrder = 1;
   public TwoDimArrayComparator () {}
   public TwoDimArrayComparator (int keyColumn) {
      this.keyColumn = keyColumn;
   }
   public TwoDimArrayComparator (int keyColumn,int sortOrder) {
   this.keyColumn = keyColumn;
   this.sortOrder = sortOrder;
   }
   public int compare(Object a, Object b) {
     if (a instanceof String[]) {
        return sortOrder * ((String[])a)[keyColumn].compareTo(((String[])b)[keyColumn]);
      } else if (a instanceof int[]){
         return sortOrder * (((int[])a)[keyColumn] - ((int[])b)[keyColumn]);
         } else {
                return 0;
            }
     }
}