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
Partner Zones AWS Cloud
by AWS Developer Relations
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
Partner Zones
AWS Cloud
by AWS Developer Relations

Trending

  • 5 Key Concepts for MQTT Broker in Sparkplug Specification
  • File Upload Security and Malware Protection
  • Chaining API Requests With API Gateway
  • A Complete Guide to AWS File Handling and How It Is Revolutionizing Cloud Storage

Trending

  • 5 Key Concepts for MQTT Broker in Sparkplug Specification
  • File Upload Security and Malware Protection
  • Chaining API Requests With API Gateway
  • A Complete Guide to AWS File Handling and How It Is Revolutionizing Cloud Storage

Understanding Code-Call Graphs

Understanding code is a daunting task, especially if it is written by someone else or not documented properly. See how this open source tool, Doxygen, can help.

Prabhu Rengaswamy user avatar by
Prabhu Rengaswamy
CORE ·
Aug. 17, 20 · Review
Like (2)
Save
Tweet
Share
3.64K Views

Join the DZone community and get the full member experience.

Join For Free

Going through the code and understanding it is a daunting task, especially if the code is written by someone else. It would be a nightmare if the code is not documented. The plight is usually for the developers who are tasked to maintain a code that is written by someone else.

Sometimes the situation is developers don't know where to begin and understanding it is, even more, a herculean task. It would be great if they had somewhere to start and understand the code that they are going to breathe through.

Enter Doxygen! Doxygen has been there for almost a quarter of a century, written by Dimitri van Heesch. There are other tools documentation generators too. Javadoc for example is very popular because of the way the code documentation is organized.

The beauty of Doxygen is it has features to help understand code better even if the code is not documented properly. It supports these source languages out of the box - C/C++, Java, Python, VHDL, PHP IDL, C#, Fortran, Objective-C 2.0, and to some extent D. It also supports a variety of output formats.

Doxygen has a robust and big set of features that this article's space is too small to contain, so we will look at it from the perspective of understanding code. Doxygen has a great feature of generating something called call-graphs. Call graphs are control flow graphs that show what all functions/methods a particular function/method calls.

An example of a call-graph would be like the diagram below

example of a call-graph

 

So to understand the code first, call-graphs are a great way to understand the code flow, even if the code is poorly or even not documented. Doxygen provides both the command-line version and a wizard that guides us through the documentation generation process

We can use either to generate the documentation, however for newbies, the wizard will help to generate the configuration file necessary to generate the documentation To generate the call graphs, Doxygen requires the dot tool to be available in the path. dot tool is a part of the Graphviz package that helps generate the call-graphs.

The Doxygen documentation page has very clear steps on how to use the wizard to generate the documentation. In the Diagrams tab, we will have to select the Call graphs option to generate the call graphs. Of course, it takes a bit of time to generate the call-graphs.

Once the documentation is generated, we can start navigating from whatever is the main class method and click on the call-graph functions to navigate through the entire code. Go ahead try Doxygen and see! In the next part of this article, we'll see about eclox, the eclipse plugin for Doxygen.

Doxygen Documentation

Published at DZone with permission of Prabhu Rengaswamy. See the original article here.

Opinions expressed by DZone contributors are their own.

Trending

  • 5 Key Concepts for MQTT Broker in Sparkplug Specification
  • File Upload Security and Malware Protection
  • Chaining API Requests With API Gateway
  • A Complete Guide to AWS File Handling and How It Is Revolutionizing Cloud Storage

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

Let's be friends: