java - FileReader 和 FileInputStream 的不同输出

Question

import java.io.FileInputStream;
import java.io.FileReader;
import java.io.IOException;
public class Main {
    public static void main(String[] args) throws IOException {
        FileReader fileReader1 = new FileReader("C:\\test\\input.txt");
        FileInputStream fileInputStream1 = new FileInputStream("C:\\test\\input.txt");
        FileReader fileReader2 = new FileReader("C:\\test\\abc.png");
        FileInputStream fileInputStream2 = new FileInputStream("C:\\test\\abc.png");

        int ab=fileReader1.read(); 
        int bc=fileInputStream1.read();

        int ab1=fileReader2.read();
        int bc1=fileInputStream2.read();

        System.out.println("reading a file : fileReader:"+ab+" fileInputStream:"+bc);
        System.out.println("resding  PNG : fileReader:"+ab1+" fileInputStream:"+bc1);
    }
}

输出:

reading a file : fileReader:104 fileInputStream:104
resding  PNG : fileReader:8240 fileInputStream:137

我正在使用 FileReader 和 FileInputStream 来读取 txt 文件和读取图像文件。我知道按字节读取和按其他字符读取。但我没有得到这个输出。

Answer 1

文件阅读器:

Convenience class for reading character files. The constructors of this class assume that the default character encoding and the default byte-buffer size are appropriate.

文件输入流:

FileInputStream is meant for reading streams of raw bytes such as image data. For reading streams of characters, consider using FileReader.