usermanager.java

自己用java写的一个类似于通讯录的东西

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

public class UserManager
{
	private ArrayList<User> users = new ArrayList<User>();
	//private ArrayList users = new ArrayList();

	public boolean loadData(String dataPath) throws IOException{
		BufferedReader br = new BufferedReader(
								new InputStreamReader(new FileInputStream(dataPath)));
		String line = null;
		User user = null;
		while( (line=br.readLine()) != null){
			if( line.charAt(0) == '#'){ //comment
				continue;
			}
			String[] items = line.split(" ");//以空格分格单词
			if( items.length != 4 ){ //format is invalid
				continue;
			}
			if( items[0].equals("0")){ //normal user
				user = new NormalUser(items[1], items[2], items[3]);
			}else{
				user = new AdvancedUser(items[1], items[2], items[3]);
			}
			users.add(user);
		}
		br.close();
		return true;
	}

	public List<User> getAllUsers(){
		return users;
	}

	public User queryUser(String id){
		for( User user : users){
			if( user.getId().equals(id)){
				return user;
			}
		}
		return null;
	}

	//finish follwoed methods
	public void addUser(User user){
		if (queryUser(user.getId())==null)
		{
			users.add(user);
			System.out.println("success!");
		}
		else System.out.println("this person has exist!");
	}

	public void updateUser(User oldUser, User newUser){

	}
	
	public void deleteUser(User user){	 //删除还有问题
		if (queryUser(user.getId())==null)
		{
			System.out.println("this person not exist!");
		}
        else {
        	user=queryUser(user.getId());
        	users.remove(user);
        	System.out.println("delete success!");
	}
	}
	
	public void saveData(String dataPath) throws IOException{
		BufferedWriter out=new BufferedWriter(new OutputStreamWriter(new FileOutputStream(dataPath)));
		Iterator<User>iter=users.iterator();
	    while (iter.hasNext())
	    {
	    	User ss=iter.next();
	    	String str=ss.toString();
	    	out.write(str);
	    	out.newLine();
	    }
	    out.close();
	}
}