Jacoco doesn't produce coverage reports

Question

I \'m using maven-sure fire plugin to execute tests and Jacoco plugin to generate the coverage reports. Jacoco does\'t provide coverage reports and instead fails with the d

Answer 1

Quoting http://www.jacoco.org/jacoco/trunk/doc/prepare-agent-mojo.html :

If your project already defines VM arguments for test execution, be sure that they will include property defined by JaCoCo.

One of the ways to do this in case of maven-surefire-plugin - is to use syntax for late property evaluation:

<plugin>
  <groupId>org.apache.maven.plugins</groupId>
  <artifactId>maven-surefire-plugin</artifactId>
  <configuration>
    <argLine>@{argLine} -your -extra -arguments</argLine>
  </configuration>
</plugin>

Another way is to define "argLine" as a Maven property rather than as part of the configuration of maven-surefire-plugin:

<properties>
  <argLine>-your -extra -arguments</argLine>
</properties>
...
<plugin>
  <groupId>org.apache.maven.plugins</groupId>
  <artifactId>maven-surefire-plugin</artifactId>
  <configuration>
    <!-- no argLine here -->
  </configuration>
</plugin>

so either define

<argLine>-Xms256m -Xmx512m -XX:MaxPermSize=128m -ea
                    -Dfile.encoding=UTF-8</argLine>

as property:

<build>
  <properties>
    <argLine>-Xms256m -Xmx512m -XX:MaxPermSize=128m -ea
                    -Dfile.encoding=UTF-8</argLine>
  </properties>
...
  <plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-surefire-plugin</artifactId>
    <version>2.10</version>
    <configuration>
      <!-- no argLine here -->

or add @{argLine} to it:

<plugin>
  <groupId>org.apache.maven.plugins</groupId>
  <artifactId>maven-surefire-plugin</artifactId>
  <version>2.10</version>
  <configuration>
    <argLine>@{argLine} -Xms256m -Xmx512m -XX:MaxPermSize=128m -ea
                    -Dfile.encoding=UTF-8</argLine>