Add a Code Coverage Build Gate in SonarQube for Java Projects

May 18, 2023

In software development, code coverage refers to the percentage of code that is covered by automated tests. Code coverage is a critical metric for determining the effectiveness of your testing strategy. SonarQube is a popular open-source platform for continuous code quality inspection that can help you keep track of your code coverage. In this blog post, we will discuss how to add a code coverage build gate in SonarQube for Java projects.

Table of Contents

Step 1: Install SonarQube

First, you need to install SonarQube on your system. You can download the latest version of SonarQube from the official website. Once you have downloaded the package, follow the installation instructions to install SonarQube on your system.

Step 2: Install SonarScanner

SonarScanner is a command-line tool used to analyze your code and send the results to SonarQube. You can download the latest version of SonarScanner from the official website. Once you have downloaded the package, follow the installation instructions to install SonarScanner on your system.

Step 3: Configure SonarScanner

Once you have installed SonarScanner, you need to configure it to work with your Java project. Create a new file named sonar-project.properties in the root directory of your project and add the following properties:

sonar.projectKey=<your-project-key>
sonar.projectName=<your-project-name>
sonar.projectVersion=<your-project-version>

sonar.sources=<your-source-folder>
sonar.java.binaries=<your-binary-folder>

Replace <your-project-key>, <your-project-name>, <your-project-version>, <your-source-folder>, and <your-binary-folder> with the appropriate values for your project. The sonar.sources property specifies the directory where your source code is located, and the sonar.java.binaries property specifies the directory where your compiled Java classes are located.

Step 4: Configure JaCoCo

JaCoCo is a Java code coverage library that SonarQube uses to calculate code coverage metrics. You need to add the JaCoCo plugin to your project and configure it to generate a coverage report.

Add the following plugin to your project’s pom.xml file:

<plugin>
    <groupId>org.jacoco</groupId>
    <artifactId>jacoco-maven-plugin</artifactId>
    <version>0.8.4</version>
    <executions>
        <execution>
            <id>prepare-agent</id>
            <goals>
                <goal>prepare-agent</goal>
            </goals>
        </execution>
        <execution>
            <id>report</id>
            <goals>
                <goal>report</goal>
            </goals>
        </execution>
    </executions>
</plugin>

This plugin sets up the JaCoCo agent to collect code coverage data and generates a report in the target/site/jacoco/index.html file.

Step 5: Integrate JaCoCo with SonarQube

To integrate JaCoCo with SonarQube, add the following properties to your sonar-project.properties file:

sonar.coverage.jacoco.xmlReportPaths=target/site/jacoco/jacoco.xml
sonar.junit.reportPaths=target/surefire-reports

The sonar.coverage.jacoco.xmlReportPaths property specifies the path to the JaCoCo coverage report, and the sonar.junit.reportPaths property specifies the path to the JUnit test reports.

Step 6: Set up a Quality Gate

A Quality Gate is a set of conditions that must be met for a project to be considered of high quality. In this step, we will set up a Quality Gate