### Question:
DN implements Comparable<DN>, Serializable { public DN getParentDNInSuffix() { if (numComponents <= 1 || DirectoryServer.isNamingContext(this)) { return null; } RDN[] parentComponents = new RDN[numComponents-1]; System.arraycopy(rdnComponents, 1, parentComponents, 0, numComponents-1); return new DN(parentComponents); } DN();  DN(RDN[] rdnComponents);  DN(List<RDN> rdnComponents);  DN(RDN rdn, DN parentDN); static DN rootDN(); boolean isRootDN(); int size(); RDN rdn(); DN rename(final DN fromDN, final DN toDN); RDN getRDN(int pos); DN parent(); DN getParentDNInSuffix(); DN child(RDN rdn); DN concat(RDN[] rdnComponents); DN child(DN relativeBaseDN); boolean isDescendantOf(DN dn); boolean isAncestorOf(DN dn); boolean matchesBaseAndScope(DN baseDN, SearchScope scope); static DN decode(ByteSequence dnString); static DN valueOf(String dnString); @Override boolean equals(Object o); @Override int hashCode(); @Override String toString(); void toString(StringBuilder buffer); String toNormalizedUrlSafeString(); ByteString toNormalizedByteString(); @Override int compareTo(DN other); static final DN NULL_DN; static final byte NORMALIZED_RDN_SEPARATOR; static final byte NORMALIZED_AVA_SEPARATOR; static final byte NORMALIZED_ESC_BYTE; }### Answer:
@Test(dataProvider = "namingContexts") public void testGetParentDNInSuffix(DN namingContext) throws Exception { assertNull(namingContext.getParentDNInSuffix()); DN childDN = namingContext.child(RDN.decode("ou=People")); assertNotNull(childDN.getParentDNInSuffix()); assertEquals(childDN.getParentDNInSuffix(), namingContext); }