What is the color and number beside the line number in cobertura report

Question

I used mvn cobertura:cobertura to generate this cobertura JUnit test coverage report. Can anyone explain to me what do the numbers beside the line number mean? Thank you.

Answer 1

Those numbers correspond to how many times that line was executed during your tests. Using a simple example:

public class MyClass {
    public void methodA(){
        System.out.println("Method a");
    }

    public void methodB(){
        System.out.println("Method b");
    }
}

With some tests:

public class MyClassTest {

    @Test
    public void testMethodA(){
        final MyClass x = new MyClass();
        x.methodA();
    }

    @Test
    public void testMethodB(){
        final MyClass x = new MyClass();
        x.methodB();
    }
}

I will get the following report, showing that I constructed my test object twice, and ran each method once:

If I add an @Ignore annotation on testMethodB, the following report is produced instead, showing that I only constructed my class once, and did not execute lines within methodB when testing:

The color is associated with coverage. It will appear red when there is no test that covers that line or branch.

Edit - Regarding your question in the comments, its possible to be missing coverage due to not checking all conditions. For example, consider this method:

public void methodB(final boolean testOne, final boolean testTwo){
    if(testOne || testTwo){
        System.out.println("Method b");
    }
    System.out.println("Done");
}

and this test:

@Test
    public void testMethodB(){
        final MyClass x = new MyClass();
        x.methodB(true, false);
        x.methodB(true, true);
    }

you will end up with the following test report. The reason for this is because although you did execute this line in the test(2 times, in fact), I did not test all permutations of my conditional, therefore, the report will show that I am missing coverage.