boy 男生 对象
package com.javaer.examples.sort;
public class Boy {
String name;//姓名
int score;// 分数
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public int getScore() {
return score;
}
public void setScore(int score) {
this.score = score;
}
}
Comparator强行对某个对象collection进行整体排序的比较函数，可以将Comparator传递给Collections.sort或Arrays.sort。
比较算法
package com.javaer.examples.sort;
import java.util.Comparator;
public class MyComparator implements Comparator {
//接口，必须实现的方法
public int compare(Object o1, Object o2) {
Boy p1 = (Boy) o1;
Boy p2 = (Boy) o2;
if (p1.score < p2.score)
return 1;
else if (p1.score > p2.score)
return -1;
else
return 0;
}
}
实际运用
package com.javaer.examples.sort;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
public class ScoreSort{
/**
* @param args
*/
public static void main(String[] args) {
List boys = new ArrayList();
Boy b = new Boy();
b.name = "tom";
b.score = 89;
boys.add(b);
b = new Boy();
b.name = "jim";
b.score = 92;
boys.add(b);
b = new Boy();
b.name = "jack";
b.score = 77;
boys.add(b);
for(int i=0 ;i < boys.size();i++){
b = (Boy)boys.get(i);
System.out.println(b.name + " : " + b.score);
}
System.out.println("------------------------");
MyComparator mc = new MyComparator();
Collections.sort(boys,mc);
for(int i=0 ;i < boys.size();i++){
b = (Boy)boys.get(i);
System.out.println(b.name + " : " + b.score);
}
}
}