Io流 FileInputStream 用read(byte[] b) 读文件

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

public class io_stream  {
    public static void main(String[] args) {
        try {
            FileInputStream file = new FileInputStream("C:\\Users\\Bi-Hu\\Desktop\\1.txt");
            byte[] arr = new byte[20];
            int temp = 0;
            while((temp = file.read(arr)) != -1){
                System.out.print(new String(arr,0,temp));
            }

        } catch (Exception e) {
            e.printStackTrace();
        }

    }
}

Io流 FileInputStream  用read(byte[] b) 读文件

它读完返回成功读了多少个的

至于new String (byte[] , x , y);
就是那么回事.....