Question

java关于collections的排序，默认是升序，为什么我这段代码得到的结果是降序？

import java.util.*;

public class TestLink {
public static void main(String[] args) {
List l = new LinkedList();
l.add(new Bbbbbbbb("f1","f2"));
l.add(new Bbbbbbbb("b2","f3"));
l.add(new Bbbbbbbb("c1","f4"));
l.add(new Bbbbbbbb("a2","f1"));
Collections.sort(l);
System.out.println(l);
}
}

class Bbbbbbbb implements Comparable {
String a,b;
public Bbbbbbbb(String a,String b) {
this.a = a;
this.b = b;
}

public boolean equals(Object obj) {

if (obj instanceof Bbbbbbbb) {
Bbbbbbbb name = (Bbbbbbbb) obj;
return (a.equals(name.b))
&& (b.equals(name.b));
}
return super.equals(obj);
}

public int hashCode() {
return a.hashCode();
}

public String toString() {
return (a+b);
}

public int compareTo(Object o) {
Bbbbbbbb ob = (Bbbbbbbb)o;
return ob.a.compareTo(this.a) != 0 ?
ob.a.compareTo(this.a) : ob.b.compareTo(this.b);
}

}

Answer 1

参数换一下顺序

追问

你是说comparaTo里的 a和b吗，这个换了没用啊