使用comparator进行数组的排序

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import java.util.Arrays;
import java.util.Collections;
import java.util.Comparator;

public class Test {

/**
* @param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub

  Student s[]=new Student[3];
  s[0]=new Student("yang",1011,80);
  s[1]=new Student("zhang",1010,90);
  s[2]=new Student("america",1012,85);
  Comparator c1=new ComparatorByName();
  Comparator c2=new ComparatorByScore();
  for(Student e:s){
   System.out.println(e.getId()+" "+e.getName()+" "+e.getScore());
  }
  Arrays.sort(s, c1);
  for(Student e:s){
   System.out.println(e.getId()+" "+e.getName()+" "+e.getScore());
  }
  Arrays.sort(s, c2);
  for(Student e:s){
   System.out.println(e.getId()+" "+e.getName()+" "+e.getScore());
  }
}

}

================================

/SortTest/src/ComparatorByScore.java

import java.util.Comparator;

public class ComparatorByScore implements Comparator<Student> {

@Override
public int compare(Student o1, Student o2) {
  // TODO Auto-generated method stub
  if(o1.getScore()>o2.getScore())return 1;
  if(o1.getScore()<o2.getScore())return -1;
  return 0;
}

}
===========================================

import java.util.Comparator;

public class ComparatorByName implements Comparator<Student> {

@Override
public int compare(Student o1, Student o2) {
// TODO Auto-generated method stub
return o1.getName().compareTo(o2.getName());
}

}
==============================================

public class Student {
String name;
int id;
int score;
public String getName() {
  return name;
}
public void setName(String name) {
  this.name = name;
}
public int getId() {
  return id;
}
public void setId(int id) {
  this.id = id;
}
public int getScore() {
  return score;
}
public void setScore(int score) {
  this.score = score;
}
public Student(String name, int id, int score) {
  super();
  this.name = name;
  this.id = id;
  this.score = score;
}
}