public synchronized Tag getTagWithId(String tagId) {
        Tag tag = this.tagMap.get(tagId);
        AssertionUtil.assertNotNull(tag, "Could not find tag with id " + tagId);
        return tag;
    }
An optional description of the test class.
jgiven-core/src/main/java/com/tngtech/jgiven/report/model/ReportModel.java