Versions Compared


  • This line was added.
  • This line was removed.
  • Formatting was changed.
titleTable of Contents

Table of Contents

There are two different ways It is possible to feed SonarQube with information on unit tests execution and code coverage :


reports from JaCoCo, Cobertura and Clover.

Project samples covering the different cases below are available on github that can be browsed or downloadedprojects/languages/java/code-coverage

 See Component Viewer on Unit Test File or Quality Flows > Lack of Unit Tests to browse the results in the web interface.

Reusing Existing Reports

Every analyzer supports the reuse reports mode.


Depending on the code coverage tool you used to generate your report, replace jacoco by cobertura or clover in the property name.

Using SonarQube Embedded Engine

Maven supports this mode with the following code coverage tools: JaCoCo, Cobertura and Clover.

The SonarQube Ant Task and the SonarQube Runner do not support this mode.


Before running an analysis with JaCoCo, the source code has to be compiled.

First, tell SonarQube to execute the unit tests and the code coverage tool:

Add this to your pom file:

Code Block

Maven Project

With Maven, then, you just have to tell SonarQube which code coverage engine you wish to use: jacoco or cobertura or clover.

Code Block
<>jacoco | cobertura | clover</>

Note that this property can be set at the SonarQube instance level through the web interface: Settings > Configuration > General Settings > Java.

Sample projects are available on github that can be browsed or downloaded:

  • Maven and JaCoCo: projects/code-coverage/ut/maven/ut-maven-jacoco-runTests
  • Maven and Cobertura: projects/code-coverage/ut/maven/ut-maven-cobertura-runTests

Maven Multi-module Project and JaCoCo

For multi-module Maven projects, compute overall code coverage by unit tests across modules. This case clearly lies between unit tests and integration tests but this is widely used.

Sample projects are available on github that can be browsed or downloadedprojects/code-coverage/combined ut-it/maven/combined-ut-it-multimodule-maven-jacoco



Mapping of Unit Tests and Covered Code

The objective is to answer the following questions:

  • Which files are covered by a given unit test?
  • How many lines of code are covered by a given unit test?
  • Which lines are covered by a given unit test?
  • Which tests cover a given line of code?

See Component Viewer on Unit Test File for more details.

A sample project is available on github that can be browsed or downloadedprojects/code-coverage/ut/maven/ut-maven-jacoco-runTests. What you need to add to your pom.xml to get this behavior is contained between "BEGIN/END: Specific to mapping unit tests and covered code" tags in the pom file. Note that you have to run the analysis with the coverage-per-test profile. Read the README file for more information.


  • JUnit 4.7+
  • Maven Surefire Plugin 2.4+ 

This feature is only available while using JaCoCo as the code coverage tool.


0% code coverage reported, but unit tests are correctly executed

This problem occurs while using the Maven Cobertura Plugin and a special configuration of the Maven Surefire Plugin prevents the unit tests from being forked. This problem can be solved by removing the line "<forkMode>never</forkMode>" in the Maven configuration file (see SONAR-1445 and MCOBERTURA-70).

java.lang.Error: Unable to access JaCoCo Agent - make sure that you use JaCoCo and version not lower than 0.6.2

There can be several reasons for this error:
  • Make sure that you do NOT set 'forkMode' to 'never' on the Surefire plugin - otherwise it will not fork the process and no JaCoCo agent will be attached.
Code Block
    <forkMode>never</forkMode> <!-- Do not set forkMode to never -->


  • Make sure that you call first mvn clean install and then mvn sonar:sonar Pcoverage-per-test separately. Indeed, only SonarQube can attach the JaCoCo agent, so mvn clean install sonar:sonar -Pcoverage-per-test will produce the error because the test phase will be executed a first time alone.