### Question:
EjbHelper { public static boolean isClassifierValid( String classifier ) { boolean result = false; if ( hasClassifier( classifier ) && classifier.matches( "^[a-zA-Z]+[0-9a-zA-Z\\-]*" ) ) { result = true; } return result; } private  EjbHelper(); static boolean isClassifierValid( String classifier ); static boolean hasClassifier( String classifier ); static File getJarFile( File basedir, String finalName, String classifier );  }### Answer:
@Test public void validClassifier() { assertThat( EjbHelper.isClassifierValid( "anton" ) ).isTrue(); }
@Test public void anOtherValidClassifier() { assertThat( EjbHelper.isClassifierValid( "jdk15" ) ).isTrue(); }
@Test public void moreValidClassifier() { assertThat( EjbHelper.isClassifierValid( "client-classifier" ) ).isTrue(); }
@Test public void isClassifierValidShouldReturnFalseIfClassifierIsPrefixedByDash() { assertThat( EjbHelper.isClassifierValid( "-anton" ) ).isFalse(); }
@Test public void isClassifierValidShouldReturnFalseIfClassifierIsNull() { assertThat( EjbHelper.isClassifierValid( null ) ).isFalse(); }