@Test
    public void testEnglishStemming() {
        var parameters = new LinguisticsParameters(Language.ENGLISH, StemMode.ALL, true, true);
        var withKstem = new OpenNlpLinguisticsTester();
        withKstem.assertTokenize("cars walking, jumps pushed", parameters, List.of("car", "walking", "jumps", "pushed"), null);

        var withSnowball = new OpenNlpLinguisticsTester(new OpenNlpConfig.Builder().snowballStemmingForEnglish(true).build());
        withSnowball.assertTokenize("cars walking, jumps pushed", parameters, List.of("car", "walk", "jump", "push"), null);
    }
Test of tokenization, with stemming and accent removal

@author matskin
@author bratseth
opennlp-linguistics/src/test/java/com/yahoo/language/opennlp/OpenNlpTokenizationTestCase.java