[Custom Java inside Maven] Maven Enforcer plugin lets you define custom conditions in a lightweight Java. https://maven.apache.org/enforcer/enforcer-rules/evaluateBeanshell.html #maven #java

pom.xml

<build>
  <plugins>
    <plugin>
      <groupId>org.apache.maven.plugins</groupId>
      <artifactId>maven-enforcer-plugin</artifactId>
      <executions>
        <execution>
          <id>check-coverage</id>
          <phase>install</phase>
          <goals>
            <goal>enforce</goal>
          </goals>
          <configuration>
            <fail>true</fail>
            <rules>
              <evaluateBeanshell>
                <message>Code coverage check failed (&lt; ${min.coverage}%)</message>
                <condition>
                  import java.io.BufferedReader;
                  import java.io.FileReader;
                  import java.text.DecimalFormat;

                  if (System.getenv("bamboo_build_working_directory") != null) {
                  	print("Skipping coverage check: running on CI");
                  	return true;
                  }

                  try {
                  	minCoverage = Float.parseFloat("${min.coverage}");
                  } catch (NumberFormatException e) {
                  	print("Skipping coverage check: no limit defined or bad format (min.coverage)");
                  	return true;
                  }

                  coverageOk = true;
                  jacocoCsv = "${project.reporting.outputDirectory}/jacoco-aggregate/jacoco.csv";
                  input = null;
                  try {
                  	missed = covered = 0;
                  	input = new BufferedReader(new FileReader(jacocoCsv));
                  	input.readLine();  // skip header line
                  	while ((line = input.readLine()) != null) {
                  		values = line.split(",");
                  		missed += Integer.parseInt(values[3]);
                  		covered += Integer.parseInt(values[4]);
                  	}
                  	total = missed + covered;
                    if (total > 0) {
                      coveragePct = covered * 100.0 / total;
                      df = new DecimalFormat("0.#");
                      print("Covered instructions overall: " + covered + "/" + total + " (" + df.format(coveragePct) + "%)");
                      coverageOk = coveragePct >= minCoverage;
                    } else {
                      print("Skipping coverage check: no coverage data found");
                    }
                  } catch (FileNotFoundException e) {
                    print("Skipping coverage check: coverage report file not found (" + jacocoCsv + ")");
                  } catch (IOException e) {
                    print("Skipping coverage check: error reading coverage report file");
                  } finally {
                  	if (input != null) {
                  		input.close();
                  	}
                    return coverageOk;
                  }
                </condition>
              </evaluateBeanshell>
            </rules>
          </configuration>
        </execution>
      </executions>
    </plugin>
  </plugins>
</build>