### Question:
PlainLiteralImpl extends AbstractLiteral implements Literal, Serializable { @Override public IRI getDataType() { return dataType; } PlainLiteralImpl(String value);  PlainLiteralImpl(String value, Language language); @Override String getLexicalForm(); @Override Language getLanguage(); @Override String toString(); @Override IRI getDataType();  }### Answer:
@Test public void checkHashCode() { String stringValue = "some text"; Language language = new Language("en"); Literal literal = new PlainLiteralImpl(stringValue, language); Assert.assertEquals(literal.getDataType().hashCode() + stringValue.hashCode() + language.hashCode(), literal.hashCode()); }