Java.io. Byte Stream

//byte stream, write string to file
	public static void main(String[] args) throws Exception {
		// where to output
		File file=new File("d:"+File.separator+"test.txt");
		
		OutputStream outputStream = new FileOutputStream(file);
		String str="1234qwer";//The written string
		
		byte[] bytes = str.getBytes();//Only byte array can be input, so convert to byte array first
		
		outputStream.write(bytes);//写入
		outputStream.close();
	}

// byte stream, read string from file
	public static void main(String[] args) throws Exception {
		// which file to read
		String path = "d:" + File.separator + "test.txt";
		File file = new File(path);

		InputStream fileInputStream = new FileInputStream(file);

		byte[] bs = new byte[1000];//All content is read into this array
		
		int read_len = fileInputStream.read(bs);//The size of the file read
		fileInputStream.close();

		System.out.println("Length of read" + read_len);
		System.out.println(new String(bs, 0, read_len));//Output to console

	}