private double mean(double[] values) {
        double sum = 0L;

        for (double v : values) {
            sum += v;
        }
        return sum / (double) values.length;
    }
Object identity is used to differentiate between different implementation strategies, toString() is used to print a report.

@return an object with a descriptive toString() for the implementation under test
vespajlib/src/test/java/com/yahoo/text/JsonMicroBenchmarkTestCase.java