点歌系统（使用了hashSet）

import java.util.*;
import java.io.*;
public class Jukebox6
{
ArrayList<Song> songList=new ArrayList<Song>();
public static void main(String [] args)
{
new Jukebox6().go();
}
public void go()
{
getSongs();
System.out.println(songList);
Collections.sort(songList);
System.out.println(songList);
HashSet<Song> songSet=new HashSet<Song>();
songSet.addAll(songList);
//System.out.println(songList);
System.out.println(songSet);
}
public void getSongs()
{
try{
File file=new File("songListMore.txt");
BufferedReader reader=new BufferedReader(new FileReader(file));
String line=null;
while((line=reader.readLine())!=null)
addSong(line);
}catch(IOException ex){ex.printStackTrace();}
}
public void addSong(String lineToParse)
{
String [] tokens=lineToParse.split("/");
Song song=new Song(tokens[0],tokens[1],tokens[2],tokens[2]);
songList.add(song);
}
}

class Song implements Comparable<Song>
{
String title;
String artist;
String rating;
String bpm;
public boolean equals(Object oSong)
{
Song s=(Song)oSong;
return getTitle().equals(s.getTitle());
}
public int hashCode()
{
return title.hashCode();
}
Song(String t,String a,String r,String b)
{
title=t;
artist=a;
rating=r;
bpm=b;
}
public int compareTo(Song s)
{
return title.compareTo(s.getTitle());
}
public String getTitle()
{
return title;
}
public String getArtist()
{
return artist;
}
public String getRating()
{
return rating;
}
public String getBpm()
{
return bpm;
}
public String toString()
{
return title;
}
}