课后作业5

public class Think1 {
    public static void main(String [] args) throws IOException {
    File f=new File("F:\\FiveOne.txt");
    System.out.println(f.length());
    
    }
}

import java.io.File;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.FileInputStream;
import java.io.FileOutputStream;
//编写一个文件加解密程序，通过命令行完成加解密工作
public class FileCode {
 private static final int numOfEncAndDec=0x99;//加密解密密钥
 private static int dataOfFile=0;//文件字节内容

 public static void main(String[] args) {
  File srcFile=new File("E:\\新建文件夹\\poem.txt");//初始化文件
  File encFile=new File("E:\\新建文件夹\\poem1.txt"); //加密文件
  File decFile=new File("E:\\新建文件夹\\poem2.txt");  //解密文件
  
  try {
   //EncFile(srcFile,encFile);  //加密操作
   //DecFile(encFile,decFile);//解密操作
    
      EncFile(srcFile,decFile);  //加密操作

 



      DecFile(decFile,encFile);
  }catch(Exception e) {
   e.printStackTrace();
  }
 }
 private static void EncFile(File srcFile,File encFile)throws Exception{
  if(!srcFile.exists()) {
   System.out.println("source file not exixt");
   }
  if(!encFile.exists()) {
   System.out.println("encrypt file created");
   encFile.createNewFile();//若无加密文件，新建一个加密文件
  }
  InputStream fis=new FileInputStream(srcFile);
  OutputStream fos=new FileOutputStream(encFile);
  
  while((dataOfFile=fis.read())>-1) {//当读到文件内容时
   fos.write(dataOfFile^numOfEncAndDec);//将读出的内容加密后写入
  }
  fis.close();
  fos.flush();
  fos.close();
 }
 private static void DecFile(File encFile,File decFile)throws Exception{
  if(!encFile.exists()) {
   System.out.println("encrypt file not exixt");
  }
  if(!decFile.exists()) {
   System.out.println("decrypt file created");
   decFile.createNewFile();
  }
  InputStream fis=new FileInputStream(encFile);
  OutputStream fos=new FileOutputStream(decFile);
  
  while((dataOfFile=fis.read())>-1) {
   fos.write(dataOfFile^numOfEncAndDec);
  }
  fis.close();
  fos.flush();
  fos.close();
 }

}

package 压缩包;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.nio.file.FileVisitResult;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.nio.file.SimpleFileVisitor;
import java.nio.file.attribute.BasicFileAttributes;
import java.util.ArrayList;

public class Test3 extends SimpleFileVisitor<Path> {
    public static ArrayList<Path> smallfiles = new ArrayList<>();
    public static void main(String[] args) {
        cut("D:/java/eclipse/压缩包/test.txt", "D:/java/eclipse/压缩包/test", 1024 * 1024 * 1);
        paste("D:/java/eclipse/压缩包/test", "D:/java/eclipse/压缩包/test0", 1024 * 1024 * 1);
    }
    public static void cut(String filepath, String endpath, int sizeofsmallfile) {//原文件，切割后小文件路径，小文件最大容量
        FileInputStream fis = null;
        File file = null;
        try {
            fis = new FileInputStream(filepath);
            file = new File(filepath);
            byte[] b = new byte[sizeofsmallfile];
            int read = 0;
            int numberofsmallfile = 1;
            while ((read = fis.read(b)) != -1) {
                String nameoflargefile = file.getName();//获取大文件全名(带扩展名)
                String nameofsmallfile = nameoflargefile.substring(0, nameoflargefile.lastIndexOf("."));//获取小文件名(不带扩展名)
                String extension = nameoflargefile.substring(nameoflargefile.lastIndexOf("."), nameoflargefile.length());  //获取扩展名
                FileOutputStream fos = new FileOutputStream(endpath + "\\" + nameofsmallfile + "-" + numberofsmallfile + extension); //创建小文件
                fos.write(b, 0, read);//写入
                fos.close();
                numberofsmallfile++;
            }
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                if (fis != null) {
                    fis.close();
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
    public static void paste(String smallfilespath, String endpath, int sizeofsmallfile) {//小文件路径，生成的大文件路径，小文件最大容量
        Path fileDirPath = Paths.get(smallfilespath);
        Test3 visitor = new Test3();
        try {
            Files.walkFileTree(fileDirPath, visitor);
            File file = new File(smallfiles.get(0).toString());
            String nameofsmallfile = file.getName();//获取第一个小文件全名(带扩展名)
            String nameoflargefile = nameofsmallfile.substring(0, nameofsmallfile.lastIndexOf("-"));//获取大文件名(不带扩展名)
            String extension = nameofsmallfile.substring(nameofsmallfile.lastIndexOf("."), nameofsmallfile.length());//获取扩展名
            FileOutputStream fos = new FileOutputStream(endpath + "\\" + nameoflargefile + extension);//创建大文件
            byte[] b = new byte[sizeofsmallfile];
            for(Path p:smallfiles) {
                FileInputStream fis = new FileInputStream(p.toString());
                int read = fis.read(b);
                fis.close();
                fos.write(b, 0, read);//写入
            }
            fos.close();
        }catch (FileNotFoundException e) {
            e.printStackTrace();
        }catch (IOException e) {
            e.printStackTrace();
        }
    }
    public FileVisitResult visitFile(Path file, BasicFileAttributes attrs) throws IOException {
        if(attrs.isRegularFile()){
            smallfiles.add(file);
        }
        return FileVisitResult.CONTINUE;
    }
}