flightschedulardaofromfile.java

一个航空管理系统的例子,可以查询航班,增加代理商等功能,大家需要的话可以看看的.

package com.tarena.abs.dao;

import com.tarena.abs.model.*;
import java.io.*;
import java.util.*;
public class FlightSchedularDAOFromFile  implements FlightSchedularDAO{
	private File file;
	private InputStream in;
	private OutputStream out;
	public FlightSchedularDAOFromFile(File file)throws FileNotFoundException{
		if(!file.exists()||file.isDirectory()){
			throw new FileNotFoundException("文件不存在，或者不是有效文件！");
		}
		this.file=file;
		//in=new FileInputStream(file);
	}
	public boolean addFlightSchedular(FlightSchedular fs) {
		HashSet hs=new HashSet();
		InputStream in=null;
		ObjectInputStream ois=null;
		OutputStream out=null;
		ObjectOutputStream oos=null;
		try {
			in=new FileInputStream(file);
			ois=new ObjectInputStream(in);
			while(in.available()>0){
				hs.add(ois.readObject());
			}
			hs.add(fs);
		} catch (Exception e) {
			e.printStackTrace();
		}finally{
			if(ois!=null)try{ois.close();}catch(IOException e){}
			if(in!=null)try{in.close();}catch(IOException e){}
		}
		
		try {
			out=new FileOutputStream(file);
			oos=new ObjectOutputStream(out);
			for(Object obj:hs){
				oos.writeObject(obj);
			}
			oos.flush();
		} catch (Exception e) {
			e.printStackTrace();
		}finally{
			if(oos!=null)try{oos.close();}catch(IOException e){}
			if(out!=null)try{out.close();}catch(IOException e){}
		}
		return false;
	}

	public FlightSchedular getFlightSchedular(String flightNumber) {
		InputStream in=null;
		ObjectInputStream ois=null;
		try {
			in=new FileInputStream(file);
			ois=new ObjectInputStream(in);
			while(in.available()>0){
				FlightSchedular fs=(FlightSchedular)ois.readObject();
				if(fs.getFlightNumber().equals(flightNumber)){
					return fs;
				}
			}
		} catch (Exception e) {
			e.printStackTrace();
		}finally{
			if(ois!=null)try{ois.close();}catch(IOException e){}
			if(in!=null)try{in.close();}catch(IOException e){}
		}
		return null;
	}

	public boolean removeFlightSchedular(String flightNumber) {
		// TODO Auto-generated method stub
		return false;
	}

}