### Question:
MavenUtils { public static boolean isValidMavenId(final String id) { return id != null && MAVEN_ID_REGEX.matcher(id).matches(); } private  MavenUtils(); static boolean isValidMavenId(final String id); static final String COORDINATE_SEPARATOR; static final Pattern MAVEN_ID_REGEX; }### Answer:
@Test public void testEmptyStringIsNotAValidId() { assertFalse(MavenUtils.isValidMavenId("")); }
@Test public void testNullIsNotAValidId() { assertFalse(MavenUtils.isValidMavenId(null)); }
@Test public void testValidArtifactIdIsAValidId() { assertTrue(MavenUtils.isValidMavenId("spring-core")); }
@Test public void testValidGroupIdIsAValidId() { assertTrue(MavenUtils.isValidMavenId("org.springframework")); }