IO buffered stream case

Core code

package ioDemo;

import java.io.*;
import java.nio.charset.StandardCharsets;

public class BufferStreamDemo {
    
    public static void main(String[] args) {
    
// byteWrite();
// byteReader();
// charReader();
        charWrite();
    }

    private static void byteWrite() {
    
        try {
    
            File file = new File("C:\\Users\\lihw\\Desktop\\test\\123.txt");
            OutputStream os = new FileOutputStream(file);
            //  Construct byte buffer stream 
            BufferedOutputStream bos = new BufferedOutputStream(os);
            bos.write(" Ha ha ha ha , This guy buffer".getBytes(StandardCharsets.UTF_8));
            bos.close();
        } catch (Exception e) {
    
            e.printStackTrace();
        }

    }

    private static void byteReader() {
    
        try {
    
            InputStream is = new FileInputStream("C:\\Users\\lihw\\Desktop\\test\\123.txt");
            BufferedInputStream bis = new BufferedInputStream(is);
            byte[] bytes = new byte[1024];
            int len = -1;

            while ((len = bis.read(bytes)) != -1) {
    
                System.out.println(new String(bytes, 0, len));
            }
            bis.close();
        } catch (Exception e) {
    
            e.printStackTrace();
        }
    }

    private static void charWrite() {
    
        File file = new File("C:\\Users\\lihw\\Desktop\\test\\123.txt");
        try (Writer writer = new FileWriter(file); BufferedWriter bw = new BufferedWriter(writer)){
    
            writer.write(" Ha ha ha , This is the test de BufferedWriter  The function of ");
        } catch (Exception e) {
    
            e.printStackTrace();
        }
    }

    private static void charReader() {
    
        File file = new File("C:\\Users\\lihw\\Desktop\\test\\123.txt");
        try (Reader reader = new FileReader(file); BufferedReader br = new BufferedReader(reader);){
    
            char[] chars = new char[1024];
            int len = -1;
            while ((len = br.read(chars)) != -1) {
    
                System.out.println(new String(chars, 0, len));
            }
        } catch (Exception e) {
    
            e.printStackTrace();
        }
    }
}