java File 读文件，复制文件

package FileDemo.Input;

import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;

public class demo1 {
    public static void main(String[] args) throws IOException {
        FileInputStream fis = new FileInputStream("stu\\src\\FileDemo\\java.txt");
        /*int read = fis.read();
        while (read != -1){
            System.out.print((char) read);
            read = fis.read();
        }*/
        int by;
        while((by = fis.read()) != -1){
            System.out.print((char)by);
        }
    }
}

复制文件
package FileDemo.Output;

import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;

public class cpdemo {
    public static void main(String[] args) throws IOException {
        // 要写入的
        FileOutputStream fos = new FileOutputStream("stu\\src\\FileDemo\\Output\\1.txt");

        // 我在读取的
        FileInputStream fis = new FileInputStream("stu\\src\\FileDemo\\java.txt");

        int by;
        while(( by=fis.read()) != -1){
            fos.write(by);
        }
        fos.close();
        fis.close();


    }
}

文档地址：

https://shimo.im/docs/YekAm5YiDOUWIV9k/ 

https://docs.qq.com/pdf/DQWRPdmlUbEtvaHlH