### Question:
PublicKeyMirrorCredential extends AbstractMirrorCredential { @Nullable public byte[] passphrase() { if (passphrase == null) { return null; } else { return passphrase.clone(); } } @JsonCreator  PublicKeyMirrorCredential(@JsonProperty("id") @Nullable String id,
                                     @JsonProperty("hostnamePatterns") @Nullable
                                     @JsonDeserialize(contentAs = Pattern.class)
                                     Iterable<Pattern> hostnamePatterns,
                                     @JsonProperty("username") String username,
                                     @JsonProperty("publicKey") String publicKey,
                                     @JsonProperty("privateKey") String privateKey,
                                     @JsonProperty("passphrase") @Nullable String passphrase);  PublicKeyMirrorCredential(@Nullable String id,
                                     @Nullable Iterable<Pattern> hostnamePatterns,
                                     String username, byte[] publicKey, byte[] privateKey,
                                     @Nullable byte[] passphrase); String username(); byte[] publicKey(); byte[] privateKey(); @Nullable byte[] passphrase(); @Override boolean equals(Object o); @Override int hashCode();  }### Answer:
@Test void testBase64Passphrase() { final PublicKeyMirrorCredential c = new PublicKeyMirrorCredential( null, null, USERNAME, PUBLIC_KEY, PRIVATE_KEY, PASSPHRASE_BASE64); assertThat(c.passphrase()).isEqualTo(PASSPHRASE.getBytes(StandardCharsets.UTF_8)); }