原方法

public static void loadFile(){
		try {
			File file = new File("Account/userAccount.txt");
			if(!file.exists()){
				System.out.println("文件不存在！");
			}
			BufferedReader br = new BufferedReader(new FileReader(file));//缓冲字节流读取文件账户密码
			String s = null;
			while((s = br.readLine())!=null){//每行读取账户密码
				String[] splits=s.split("\\s"); 
				Util.map.put(splits[0], splits[1]);
			}
			br.close();	
		} catch (Exception e) {
			e.printStackTrace();
		}
	}

换成字节流读取之后方法：

public static void loadFile(){
		try {
			Resource resource = new ClassPathResource("Account/userAccount.txt");
			InputStream inputStream = resource.getInputStream();
			if(!resource.exists()){
				System.out.println("文件不存在！");
			}
			BufferedInputStream bufferedInputStream = new BufferedInputStream(inputStream);
			BufferedReader bufferreader = new BufferedReader(new InputStreamReader(bufferedInputStream,StandardCharsets.UTF_8));
			String s = null;
			while((s = bufferreader.readLine())!=null){//每行读取账户密码
				String[] splits=s.split("\\s"); 
				Util.map.put(splits[0], splits[1]);
			}
			bufferreader.close();
		} catch (Exception e) {
			e.printStackTrace();
		}
	}

关键代码：

BufferedInputStream bufferedInputStream = new BufferedInputStream(inputStream);
			BufferedReader bufferreader = new BufferedReader(new InputStreamReader(bufferedInputStream,StandardCharsets.UTF_8));

注意：根据文件编码选择正确的编码格式。