I/O流实现文件内容复制

Java I/O流实现文件内容复制

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package com.practice;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Scanner;
/***
    * 复制功能   
    * @author HDC
    */
public class Copy {
	public static void main(String[] args) {
		try {
			Scanner scn = new Scanner(System.in);
			System.out.println("请输入要复制文件的路径");
			String path1 = scn.next();
			System.out.println("请输入复制文件的新名字");
			String path2 = scn.next();
			File f1 = new File(path1);
			File f2 = new File(path2);
			// 判断文件是否存在
			if (!f1.exists()) {
				f1.createNewFile();
			}
			if (!f2.exists()) {
				f2.createNewFile();
			}
			// 创建输入输出流
			InputStream in = new FileInputStream(f1);
			OutputStream out = new FileOutputStream(f2);
			byte[] b = new byte[1024];
			int len = 0;
			// 查看原文件是否有内容,若没有手动输入
			if ((len = in.read(b)) == -1) {
				System.out.println("源文件为空，请手动输入再复制");
				String s = scn.next();
				OutputStream out1 = new FileOutputStream(f1);
				out1.write(s.getBytes());
				out1.flush();
				out1.close();
			} else {
				out.write(b, 0, len);
			}
			while ((len = in.read(b)) != -1) {
				out.flush();
				out.write(b, 0, len);
				out.flush();
			}
			System.out.println("复制成功");
			in.close();
			out.close();
		} catch (Exception e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}
}