Diffblue Cover is an automated unit test-writing tool. It analyses your existing Java application and writes unit tests that reflect the current behavior, increasing test coverage and helping you find regressions in future code changes. Diffblue Cover automatically maintains the tests by updating them when your code changes. It supports standard Java 8, 11 and 17, Spring and Spring Boot.
Diffblue Cover is available as Diffblue Cover CLI and the Diffblue Cover plugin for IntelliJ

Below is a feature comparison:

Operating Systems

CLI IntelliJ Plugin
Windows 10 Enterprise
Ubuntu 18.04
RHEL 7.7
macOS 10.15

Hardware Requirements

CLI IntelliJ Plugin
Minimum RAM
16 GB 16 GB
Minimum disk space
5 GB 5 GB
4 4
TCP connection
Cover requires the use of an analysis service that communicates with the plugin and CLI via TCP connections on localhost. In particular, Cover must be able to start up the analysis service, and open a TCP connection from the frontend to the service, and from the service to the frontend.

IntelliJ Versions

We support the latest and the previous version, currently IntelliJ 2022.3 and IntelliJ 2022.2.

CLI IntelliJ Plugin
IntelliJ Community 2022.3
IntelliJ Ultimate 2022.3
IntelliJ Community 2022.2
IntelliJ Ultimate 2022.2

Java Versions

CLI IntelliJ Plugin
Open JDK, Oracle JDK 8 (version 161+), 11 (but please note that Java 11.0.7 is NOT supported) and 17. Only 64 bit versions of Java are supported.

Spring Versions

CLI IntelliJ Plugin
Spring Boot 1.3.3 to 2.7.x, Spring Core 4.1.1 to 5.3.x for Java 8
Spring Boot 2.1.0 to 2.7.x, Spring Core 5.1.0 to 5.3.x for Java 11
Spring Boot 2.4.0 to 2.7.x, Spring Core 5.3.x for Java 17

Build Tools

CLI IntelliJ Plugin
Maven 3.2.5+, Gradle 4.9+ (must be compatible with your version of Java).

Test Frameworks

CLI IntelliJ Plugin
JUnit 4.7 - 4.13, JUnit 5.0 - 5.9.2

Mock Frameworks

CLI IntelliJ Plugin
Mockito 1.9.5 - 4.11.0 for Java 8
Mockito 2.22.0 - 4.11.0 for Java 11
Mockito 4.1.0 - 4.11.0 forJava 17

Code Coverage Library

CLI IntelliJ Plugin
JaCoCo 0.8.3 +

Coverage Measurement

CLI IntelliJ Plugin
Externally via JaCoCo, SonarQube etc.

Creating Tests - Scope

CLI IntelliJ Plugin
Per method
Per class
Per package
This feature is not available for the IntelliJ Plugin Community Edition
Per module
Exclude methods from analysis

Incremental test updating

CLI IntelliJ Plugin
Use git diff patch file to update tests (


CLI IntelliJ Plugin
Export detailed JSON report


CLI IntelliJ Plugin
Web based dashboard


CLI IntelliJ Plugin
Zip bundle
Via JetBrains marketplace or customised install bundle


CLI IntelliJ Plugin
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