每天一次IO流复习

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;
/**
 * 文件工具类
 * @author stu
 *
 */
public class FileUtil {
	/**
	 * 拷贝文件的方法
	 * @param from 从哪儿复制
	 * @param to 复制到哪儿去
	 */
	public void copyFile(String from,String to){
		FileInputStream fis = null;//声明流对象
		FileOutputStream fos = null;
		try {
			fis = new FileInputStream(from);//实例化流对象
			fos = new FileOutputStream(to);
			byte [] bytes = new byte[1024];//缓冲字节数组 
			int len = 0;
			//循环写到输出流中去
			while((len = fis.read(bytes))!=-1){
				fos.write(bytes, 0, len);//写数据出去，bytes数组中从0开始到len结束
			}
		} catch (FileNotFoundException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		}finally{
			//关闭流，一定要关闭，遵循原则先开后关，后开先关
			if(fos !=null)
				try {
					fos.close();
				} catch (IOException e) {
					e.printStackTrace();
				}
			if(fis !=null)
				try {
					fis.close();
				} catch (IOException e) {
					e.printStackTrace();
				}
		}
	}
	/**
	 * 读取与写出去文本文件
	 * @param from 读取文本文件的路径
	 * @param to 写出去文本文件的路径
	 */
	public void readWriteFile(String from,String to){
		FileReader fr = null;//声明字符输入流
		BufferedReader br = null;//声明缓冲输入流
		FileWriter fw = null;//声明字符输出流
		BufferedWriter bw = null;//声明缓冲输出流
		StringBuilder sb = new StringBuilder();//
		try {
			fr = new FileReader(from);//实例化各种流对象
			br = new BufferedReader(fr);
			fw = new FileWriter(to);
			bw = new BufferedWriter(fw);
			String temp = null;
			while((temp = br.readLine())!=null){
				sb.append(temp+"\n");
			}
			bw.write(sb.toString());//使用缓冲输出流写出字符串
		} catch (FileNotFoundException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		}finally{
			//关闭流
			if(bw !=null)
				try {
					bw.close();
				} catch (IOException e3) {
					e3.printStackTrace();
				}
				if(fw !=null)
					try {
						fw.close();
					} catch (IOException e2) {
						e2.printStackTrace();
					}
					if(br !=null)
						try {
							br.close();
						} catch (IOException e1) {
							e1.printStackTrace();
						}
						if(fr !=null)
							try {
								fr.close();
							} catch (IOException e) {
								e.printStackTrace();
							}
		}
	}
	
	/**
	 * 
	 * @param path 对象写到哪儿去
	 * @param obj 写出去的对象，必须进行序列化
	 */
	public void writeObject(String path ,Object obj){
		ObjectOutputStream oos = null;//声明对象输出流对象
		FileOutputStream fos = null;
		try {
			fos = new FileOutputStream(path);
			oos = new ObjectOutputStream(fos);
			oos.writeObject(obj);//对象输出流写出去对象
		} catch (FileNotFoundException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		}finally{
			//关闭流
			if(oos !=null)
				try {
					oos.close();
				} catch (IOException e) {
					e.printStackTrace();
				}
			if(fos !=null)
				try {
					fos.close();
				} catch (IOException e) {
					e.printStackTrace();
				}
		}
	}
	/**
	 * 读取对象
	 * @param path 对象所在的文件路径
	 * @return 读取出来的对象
	 */
	public Object readObject(String path){
		FileInputStream fis = null;//声明流对象
		ObjectInputStream ois = null;
		Object obj = null;
		try {
			fis = new FileInputStream(path);//实例化流对象
			ois = new ObjectInputStream(fis);
			obj = ois.readObject();//使用对象输入流读取对象
		} catch (FileNotFoundException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		} catch (ClassNotFoundException e) {
			e.printStackTrace();
		}finally{
			//关闭流
			if(ois !=null)
				try {
					ois.close();
				} catch (IOException e) {
					e.printStackTrace();
				}
			if(fis !=null)
				try {
					fis.close();
				} catch (IOException e) {
					e.printStackTrace();
				}
		}
		return obj;
	}
	/**
	 * 
	 * @author stu
	 *		序列化对象就是实现Serializable接口
	 */
	class Goods implements Serializable{
		private String name ;
		public String getName() {
			return name;
		}
		public void setName(String name) {
			this.name = name;
		}
		public double getPrice() {
			return price;
		}
		public void setPrice(double price) {
			this.price = price;
		}
		private double price;
	}
}