How to Generate Emma Code Coverage Report for Maven Project

How to Generate Emma Code Coverage Report for Maven Project

Features of EMMA: ● Supported coverage types: class, method, line, basic block. EMMA can detect when a single source code line is covered only partially. ● Coverage stats are aggregated at method, class, package, and “all classes” levels. ● Output report types: plain text, HTML, XML. All report types support drill-down, to a user-controlled detail depth. The HTML report supports source code linking.

● Output reports can highlight items with coverage levels below user-provided thresholds. ● EMMA can instrument individual .class files or entire .jars (in place, if desired). Efficient coverage subset filtering is possible, too. ● Makefile and ANT build integration are supported on equal footing. ● EMMA is quite fast: the runtime overhead of added instrumentation is small (5-20%) and the bytecode instrumentation itself is very fast (mostly limited by file I/O speed). Memory overhead is a few hundred bytes per Java class. ● EMMA is 100% pure Java, has no external library dependencies, and works in any Java JVM.

Step1:- G ​ enerate Emma Code Coverage Report​: To generate only emma code coverage report we don't need to do anything, just type the Maven command “mvn emma:emma” to run the maven-emma-plugin.

Maven will compile the code, run unit test and Emma plugin will generate the code coverage report at ${project}/target/site/index.html.

Here is the sample of Emma code coverage report: Step2:- Integrate into the Maven Build:

We can also include the “emma-maven-plugin” in the build section. To integrate Emma into maven build we need add entry in POM.xml file.

EMMA plugin entry would be like: Step3:- To compile maven-emma-plugin type the following Maven command “mvn clean install -Pemma”.

Step 4:-Maven will compile the code, run unit test and Emma plugin will generate the code coverage report at ${project}/target/generated-classes/emma