DZone
Thanks for visiting DZone today,
Edit Profile
  • Manage Email Subscriptions
  • How to Post to DZone
  • Article Submission Guidelines
Sign Out View Profile
  • Post an Article
  • Manage My Drafts
Over 2 million developers have joined DZone.
Log In / Join
Refcards Trend Reports Events Over 2 million developers have joined DZone. Join Today! Thanks for visiting DZone today,
Edit Profile Manage Email Subscriptions Moderation Admin Console How to Post to DZone Article Submission Guidelines
View Profile
Sign Out
Refcards
Trend Reports
Events
Zones
Culture and Methodologies Agile Career Development Methodologies Team Management
Data Engineering AI/ML Big Data Data Databases IoT
Software Design and Architecture Cloud Architecture Containers Integration Microservices Performance Security
Coding Frameworks Java JavaScript Languages Tools
Testing, Deployment, and Maintenance Deployment DevOps and CI/CD Maintenance Monitoring and Observability Testing, Tools, and Frameworks
Culture and Methodologies
Agile Career Development Methodologies Team Management
Data Engineering
AI/ML Big Data Data Databases IoT
Software Design and Architecture
Cloud Architecture Containers Integration Microservices Performance Security
Coding
Frameworks Java JavaScript Languages Tools
Testing, Deployment, and Maintenance
Deployment DevOps and CI/CD Maintenance Monitoring and Observability Testing, Tools, and Frameworks
What's in store for DevOps in 2023? Hear from the experts in our "DZone 2023 Preview: DevOps Edition" on Fri, Jan 27!
Save your seat
  1. DZone
  2. Data Engineering
  3. Data
  4. Reading UTF-8 Characters From An Infinite Byte Stream

Reading UTF-8 Characters From An Infinite Byte Stream

Mike Hadlow user avatar by
Mike Hadlow
·
Aug. 07, 12 · Interview
Like (0)
Save
Tweet
Share
7.04K Views

Join the DZone community and get the full member experience.

Join For Free

I’ve been playing with the twitter streaming API today. In very simple terms, you make an HTTP request and then sit on the response stream reading objects off it. The stream is a stream of UTF-8 characters and each object is a JSON encoded data structure terminated by \r\n. Simple I thought, I’ll just create a StreamReader and set up a while loop on its Read method. Here’s my first attempt …

using(var reader = new StreamReader(stream, Encoding.UTF8))
{
    var messageBuilder = new StringBuilder();
    var nextChar = 'x';
    while (reader.Peek() >= 0)
    {
        nextChar = (char)reader.Read()
        messageBuilder.Append(nextChar);

        if (nextChar == '\r')
        {
            ProcessBuffer(messageBuilder.ToString());
            messageBuilder.Clear();
        }
    }
}

Unfortunately it didn’t work. The StreamReader maintains a small internal buffer so I wouldn’t see the \r\n combination that marked the end of a new tweet until the next tweet came along and flushed the buffer.

OK, so let’s just read each byte from the stream and convert them one-by-one into UTF-8 characters. This works fine when your tweets are all in English, but UTF-8 can have multi-byte characters; any Japanese tweets I tried to read failed.

Thanks to ‘Richard’ on Stack Overflow the answer turned out to be the Decoder class. It  buffers the bytes of incomplete UTF-8 characters, allowing you to keep stacking up bytes until they are complete. Here’s revised example that works great with Japanese tweets:

int byteAsInt = 0;
var messageBuilder = new StringBuilder();
var decoder = Encoding.UTF8.GetDecoder();
var nextChar = new char[1];

while ((byteAsInt = stream.ReadByte()) != -1)
{
    var charCount = decoder.GetChars(new[] {(byte) byteAsInt}, 0, 1, nextChar, 0);
    if(charCount == 0) continue;

    Console.Write(nextChar[0]);
    messageBuilder.Append(nextChar);

    if (nextChar[0] == '\r')
    {
        ProcessBuffer(messageBuilder.ToString());
        messageBuilder.Clear();
    }
}
UTF-8 Stream (computing) Data Types

Published at DZone with permission of Mike Hadlow, DZone MVB. See the original article here.

Opinions expressed by DZone contributors are their own.

Popular on DZone

  • Unleashing the Power of JavaScript Modules: A Beginner’s Guide
  • Why Does DevOps Recommend Shift-Left Testing Principles?
  • Leaders Make Their Own Problems
  • Exploring the Benefits of Cloud Computing: From IaaS, PaaS, SaaS to Google Cloud, AWS, and Microsoft

Comments

Partner Resources

X

ABOUT US

  • About DZone
  • Send feedback
  • Careers
  • Sitemap

ADVERTISE

  • Advertise with DZone

CONTRIBUTE ON DZONE

  • Article Submission Guidelines
  • Become a Contributor
  • Visit the Writers' Zone

LEGAL

  • Terms of Service
  • Privacy Policy

CONTACT US

  • 600 Park Offices Drive
  • Suite 300
  • Durham, NC 27709
  • support@dzone.com
  • +1 (919) 678-0300

Let's be friends: