编程笔记8

2018年7月25日

今天主要的案例是，IO流，数据的读入和写出。还有加密和解密。

IO操作的三步骤，第一步，定位，第二步，创建管道，第三步，操作管道。

产生秘钥文件代码：

import java.io.*;

public class MyKey{

public static void main(String args[]){

try{

//location

File outFile=new File("C:/Users/Administrator/Desktop/code/day8/key.txt");

//create channel

FileOutputStream fos=new FileOutputStream(outFile);

//operating channel

for(int i=0;i<128;i++){

System.out.print(i);

fos.write((int)(Math.random()*128));

}

}catch(Exception e){}

}

}

文件加密代码：

import java.io.*;

public class MyEncrypt{

public static void main(String args[]){

try{

//location

File keyFile=new File("C:/Users/Administrator/Desktop/code/day8/key.txt");

File srcFile=new File("C:/Users/Administrator/Desktop/code/day8/srctest.txt");

File outFile=new File("C:/Users/Administrator/Desktop/code/day8/encryptest.txt");

//create channel

FileInputStream fisKey=new FileInputStream(keyFile);

FileInputStream fisSrc=new FileInputStream(srcFile);

FileOutputStream fos=new FileOutputStream(outFile);

//operating channel

int lenKey=fisKey.available();

int lenSrc=fisSrc.available();

int keyB[]=new int[lenKey];

for(int i=0;i

keyB[i]=fisKey.read();

//System.out.println(fisKey.read());

}

for(int i=0;i

//System.out.print(keyB[i%128]);

fos.write(fisSrc.read()+keyB[i%128]);

}

}catch(Exception e){}

}

}

文件解密代码：

import java.io.*;

public class MyDecrypt{

public static void main(String args[]){

try{

//location

File enFile=new File("C:/Users/Administrator/Desktop/code/day8/encryptest.txt");

File keyFile=new File("C:/Users/Administrator/Desktop/code/day8/key.txt");

File deFile=new File("C:/Users/Administrator/Desktop/code/day8/detest.txt");

//create channel

FileInputStream fisKey=new FileInputStream(keyFile);

FileInputStream fisDe=new FileInputStream(enFile);

FileOutputStream fos=new FileOutputStream(deFile);

//operating channel

int keyLen=fisKey.available();

int enLen=fisDe.available();

int key[]=new int[keyLen];

for(int i=0;i

key[i]=fisKey.read();

}

for(int i=0;i

fos.write(fisDe.read()-key[i%128]);

}

}catch(Exception e){}

}

}