Blink- A command line tool to find broken URL

September 25, 2020

The inner workings of the application is very simple. It reads every line of the given file and extracts all the HTTP/HTTPS scheme URLs. It then makes HTTP/HTTPS header request to the URL and based on the status of the request it determines whether it is a bad URL or a good URL. The application currently supports color output in the Linux terminal.

Showing Blink Output

Available Features

  • Running the tool with no arguments prints a help message to guide user how to use it
  • The application can take a file name in current directory or a file path and processes the file to find the broken links
  • It processes links with HTTP/HTTPS scheme
  • Prints “GOOD”/“BAD” status based on HTTP response. See the response code at
  • Prints “REDIRECT”, if an URL was redirected
  • Color output of the result
  • Save the result in a file

How to Use the Application

Check out this repository

My Learning

The project was interesting and I learned several new things. I have used Java to write the application and Maven as the build tool.

Maven Build Tool

Maven is a popular build tool that automates the build process of application. I have used Maven for the first time in my project. The learning curve was steep. But after I leaned some basic commands, it was easy to compile and test the application.

Color Output in Terminal

Color output in terminal was new to me. I used an open source library for this purpose. The library supports Java +8, Linux, macOS, Windows 10. This was perfect for color outputting text across platforms. Here is the GitHub Repo and here is the Maven Repo.

Open Source Licensing

I have added MIT License to my project. I have yet to learn details about different licenses.

What’s Next

The application has lots of room to improve. Currently, I am making the HTTP request asynchronously using the HttpURLConnectionclass. But, I have found a new library for doing that in more efficient way. It is called async-http-client. See their github repository here Moreover, the project is open to any contribution.