accountfiledao.java

一个ATM银行模拟系统

package dao.impl;
import java.util.*;
import java.io.*;
import model.*;
import dao.AccountDao;
public class AccountFileDao implements AccountDao {
	private String fileName;
	public AccountFileDao(String fileName){
		this.fileName=fileName;
	}
	public Map loadAccounts() {
		Map accounts=new HashMap();
		ObjectInputStream in=null;
		try {
			FileInputStream fis=new FileInputStream(fileName);
			in=new ObjectInputStream(fis);
			while(true){
				Object o=in.readObject();
				Account c=(Account)o;
				accounts.put(new Long(c.getId()),c);
			}
		}catch (IOException e) {
		} catch (ClassNotFoundException e) {
		}
		finally{
			try {
				if (in!=null) in.close();
			} catch (IOException e) {
				e.printStackTrace();
			}
		}
		return accounts;
	}
	public void saveAccounts(Map accounts) {
		ObjectOutputStream out=null;
		try {
			FileOutputStream fos=new FileOutputStream(fileName);
			out = new ObjectOutputStream(fos);
			Collection as=accounts.values();
			Iterator it=as.iterator();
			while(it.hasNext()){
				Object o=it.next();
				out.writeObject(o);
			}
		} catch (IOException e) {
			e.printStackTrace();
		}
		finally{
			try {
				if (out!=null) out.close();
			} catch (IOException e) {
				e.printStackTrace();
			}
		}
	}
	

}