Diffblue Cover enables Continuous Integration for Java development

Cover is available as an IntelliJ Plugin and a CLI Tool

What does Diffblue Cover do?

Diffblue Cover analyzes your existing Java program and writes unit regression tests that reflect the current behavior of the code.

When your code's behavior changes, Diffblue Cover's tests alert you.

How does it work?

Diffblue Cover is software for Linux and Windows that runs 100% locally on your computer.

You can run it on your entire Java project, just one class, or anything in between. It gets your project structure and dependencies from Maven or Gradle. Cover supports Spring Java apps and writes tests that use standard Spring idioms and mocking.

How do I use it?

Cover is available as a CLI tool and as a plugin for IntelliJ IDEA

Plugin CLI

All Plans

IntelliJ Plugin

The IntelliJ IDEA Plugin is available for all editions of Diffblue Cover. It can generate tests per method or per class within the IDE.

The plugin can be used for interactive test writing on the developer desktop, and supports test-driven development (TDD) by quickly generating unit regression tests for utility code in bulk—so you can spend your time writing testable code, and unit tests that cover the complex, critical business logic.

Diffblue Cover creating unit tests in the IntelliJ Plugin

Available with all product plans.

You can find more information about the Cover IntelliJ Plugin in our Getting Started Documentation or our Knowledge Base.

Why use it?

Diffblue Cover helps you...


  • Improve the efficiency and quality of the software your organization delivers
  • Catch bugs and regressions before they get to the customer
  • Save the business time and money on software engineering

Manager, VP or Director

  • Build and scale faster
  • Improve your team's development efficiency
  • Increase code coverage in key applications
  • Complement existing test suites with tests that can catch cases developers might miss

DevOps Engineer

  • Catch errors, bugs, and regressions early and often
  • Streamline your CI pipeline, improving lead time, deployment frequency, velocity, mean time to restore (MTTR) and change fail percentage
  • Integrate with more confidence

Software Developer

  • Find and fix regressions and bugs more quickly
  • Improve the quality of the software you deliver
  • Free up time to focus on creating interesting new features

Ready to try Diffblue Cover?

Get started now


What is Diffblue Cover?

Diffblue Cover creates suites of unit tests that run in your continuous integration pipeline between versions and protect against regressions, so you can catch errors faster and earlier in the software development lifecycle. To learn more, see our our product page.

What are the benefits of using Diffblue Cover?

Diffblue Cover helps your team increase automation of your CI pipeline.

For development teams, this:

  • improves velocity and quality of the software you deliver
  • frees up time to focus on creating new features

For DevOps teams, this:

  • helps catch errors and issues earlier (shift left!)
  • improves deployment frequency, lead time, and mean time to repair (MTTR)

Will the tests find regressions in my code?

Yes. Diffblue Cover quickly generates tests that will allow you to adopt CI. The generated tests will help developers quickly identify regressions in subsequent commits before committing new versions.

What are the requirements for running Diffblue Cover?

See the product datasheet for more information.

How can I learn more about customers using Diffblue Cover?

See our case study on how Goldman Sachs has benefited from using Diffblue Cover to increase coverage and create a safety net against regressions.

How do we maintain Diffblue unit tests in the future?

Diffblue regression suites are maintained automatically and updated with each new code version to capture the current behavior of the code.

How does Diffblue Cover help me adopt Continuous Integration?

Diffblue Cover AI analyzes your code and writes Java unit tests that run in a CI pipeline after each commit. Cover’s tests:

  • Always compile
  • Run quickly
  • Detect regressions from previous versions
  • Improve coverage
  • Are easy to understand

Should our team stop writing unit tests after adopting Diffblue Cover?

No. Diffblue Cover is meant to complement your own unit tests and help you catch regressions.

How is a unit test different from a Diffblue regression suite?

Developers write individual unit tests to test specific functionality. Diffblue regression suites are generated automatically to help find regressions early in the development cycle. Find out more in our Unit Regression Tests eBook.