In Clover HTML reports, test coverage is indicated by the following color-coded legend.

 

 

The page margin has three color indicators:

  • left half with line number is the "optimistic marker", which is highlighted in:
    • green when at least part of the code line was covered during execution
    • otherwise red if it was not covered at all
  • right half with number of hit counts (i.e. how many times given line was executed) is the "pessimistic marker" which is highlighted in 
    • red if at least part of line was not executed or when branch expression was not evaluated to both true and false
    • otherwise green if the whole line was fully covered
  • narrow strip related with per-test code coverage, which is:
    • dark green if given source line was executed at least once from a successful test case (i.e. test has passed), or
    • dark yellow if given source line was executed from one or more test cases, but all tests were failed or
    • empty if given code was not executed from a test case (for instance from "main()" method or called by JVM GC "finalize()" method)