LinkedList的例子

写一个订票系统，可以实现的功能有订票，退票，查询票是否已经被订，打印所有订票的人！！！

import java.io.*;
import java.util.*;


public class TicketProgram {

    /**
     * @param args
     */
    LinkedList<Passenger> Plist=new LinkedList<Passenger>();
    private BufferedReader buffer=new BufferedReader(new InputStreamReader(System.in));
    public String GetString(String msg){
        System.out.println(msg);
        String out=null;
        try {
            out = buffer.readLine();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        return out;
    }
    public void run(){
        while(true){
            char option=GetString("\nEnter one of the following options\n"+
                                    "1.Book ticket!\n"+
                                    "2.Return a ticket!\n"+
                                    "3.Check a ticket!\n"+
                                    "4.Show passenger !\n"+
                                    "5.exit!").charAt(0);
            switch(option){
            case '1': BookTicket(); break;
            case '2': ReturnTicket(); break;
            case '3': Check(); break;
            case '4': Show(); break;
            case '5': return ;
            default : System.out.println("Wrong option,try again!");
            }
        }
    }
    public void BookTicket(){
        String Passname=GetString("Please enter your name");
        Passenger newpass=new Passenger(Passname);
        if(Plist.contains(newpass)){
            if(((Passenger)Plist.get(Plist.indexOf(newpass))).Ticketnum==0){
                int id=Integer.parseInt(GetString("please enter the ticket id:"));
                ((Passenger)Plist.get(Plist.indexOf(newpass))).Ticketnum=id;
                System.out.println("book a ticked");
            }
            else{
                System.out.println("Do not book again! please return first! ");
            }
        }
        else{
            int id=Integer.parseInt(GetString("please enter the ticket id:"));
            newpass.Ticketnum=id;
            Plist.add(newpass);
            System.out.println("book a ticked");
        }
    }
    public void ReturnTicket(){
        String Passname=GetString("Please enter your name");
        Passenger newpass=new Passenger(Passname);
        if((Plist.contains(newpass))){
            ((Passenger)Plist.get(Plist.indexOf(newpass))).Ticketnum=0;
        }
        else{
            System.out.println("You do not book ticket!");
        }
    }
    public void Check(){
        int id=Integer.parseInt(GetString("please enter the ticket id:"));
        for(ListIterator<Passenger> it=Plist.listIterator();it.hasNext();){
            if(it.next().Ticketnum==id){
                System.out.println("The ticket have been booked!");
                return ;
        }
        }
        System.out.println("The ticket have not been booked!");
    }
    public void Show(){
        for(ListIterator<Passenger> it=Plist.listIterator();it.hasNext();){
            System.out.println(it.next().name);
        }
    }
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        TicketProgram tk=new TicketProgram();
        tk.run();
    }

}

class Passenger{
    String name;
    int Ticketnum=0;
    public Passenger(){
    }
    public Passenger(String str,int id){
        this.name=str;
        this.Ticketnum=id;
    }
    public Passenger(String str){
        this.name=str;
    }
    public boolean equals(Object obj){
        return (this.name.equals(((Passenger)obj).name));
    }
}