java中讲讲FileInputStream的用法，举例？

2.2 FileInputStream的用法

FileInputStream是InputStream的继承类，从字面上就可看出，它的主要功能就是能从磁盘上读入文件。read方法会一个一个字节的从磁盘往回读数据。

例：2.2.1

import java.io.*;
public class TestMark_to_win {
    public static void main(String args[]) throws Exception {
        int size;
        FileInputStream f1 = new FileInputStream("c:/1.txt");
        /*Returns the number of bytes that can be read from this file input
stream without blocking.*/
        size = f1.available();
        for (int i = 0; i < size; i++) {
            /*Reads a byte of data from this input stream. This method blocks
if no input is yet available. Returns: the next byte of data, or
-1 if the end of the file is reached.*/
            System.out.println((char) f1.read());

        }

        int size2;
        FileInputStream f2 = new FileInputStream("c:/1.txt");
        size2 = f2.available();
        for (int i = 0; i < size2; i++) {
            /* you use the next statement, only int value can be printed out. */
            System.out.println(f2.read());

        }

    }
}

更多请见：https://blog.csdn.net/qq_44639795/article/details/102535689