Add coverage reporting

pom.xml

@@ -45,7 +45,7 @@
 			<id>sk89q-repo</id>
 			<url>http://maven.sk89q.com/repo/</url>
 		</repository>
-		
+
 		<repository>
 			<id>gray-snapshot</id>
 			<url>https://repo.craftyn.com/repository/graywolf336-snapshots/</url>
@@ -265,11 +265,43 @@
 				</executions>
 			</plugin>
 
+			<!-- https://www.petrikainulainen.net/programming/maven/creating-code-coverage-reports-for-unit-and-integration-tests-with-the-jacoco-maven-plugin/ -->
+			<plugin>
+				<groupId>org.jacoco</groupId>
+				<artifactId>jacoco-maven-plugin</artifactId>
+				<version>0.7.8</version>
+				<executions>
+					<execution>
+						<id>pre-unit-test</id>
+						<goals>
+							<goal>prepare-agent</goal>
+						</goals>
+						<configuration>
+							<destFile>${project.build.directory}/coverage-reports/jacoco-ut.exec</destFile>
+							<propertyName>surefireArgLine</propertyName>
+						</configuration>
+					</execution>
+					<execution>
+						<id>post-unit-test</id>
+						<phase>test</phase>
+						<goals>
+							<goal>report</goal>
+						</goals>
+						<configuration>
+							<dataFile>${project.build.directory}/coverage-reports/jacoco-ut.exec</dataFile>
+							<outputDirectory>${project.reporting.outputDirectory}/jacoco-ut</outputDirectory>
+						</configuration>
+					</execution>
+				</executions>
+			</plugin>
+
 			<plugin>
 				<groupId>org.apache.maven.plugins</groupId>
 				<artifactId>maven-surefire-plugin</artifactId>
 				<version>2.11</version>
 				<configuration>
+					<!-- Sets the VM argument line used when unit tests are run. -->
+					<argLine>${surefireArgLine}</argLine>
 					<parallel>methods</parallel>
 					<threadCount>10</threadCount>
 					<excludes>