@Test
    public void testUseAfterClose() {
        keyManager.close();
        assertThrows(IllegalStateException.class, () -> keyManager.storeSessionKey("session", testKey, "AES"));
    }

    @Test
    public void testMultipleCloseCalls() {
        keyManager.storeSessionKey("session", testKey, "AES");

        keyManager.close();
        keyManager.close(); // Should not throw

@defaultMessage Use org.elasticsearch.common.Randomness#get for reproducible sources of randomness
java.util.Random#<init>()
java.util.concurrent.ThreadLocalRandom

java.security.MessageDigest#clone() @ use org.elasticsearch.common.hash.MessageDigests

@defaultMessage Don't use MethodHandles in slow ways, don't be lenient in tests.
java.lang.invoke.MethodHandle#invoke(java.lang.Object[])

 *
 * <p><b>Warning:</b> The methods of {@code ForwardingSortedSet} forward <i>indiscriminately</i> to
 * the methods of the delegate. For example, overriding {@link #add} alone <i>will not</i> change
 * the behavior of {@link #addAll}, which can lead to unexpected behavior. In this case, you should
 * override {@code addAll} as well, either providing your own implementation, or delegating to the

   *     method
   * @throws IOException if {@code swallowIOException} is false and {@link Flushable#flush} throws
   *     an {@code IOException}.
   * @see Closeables#close
   */
  @SuppressWarnings("IdentifierName") // See Closeables.close
  public static void flush(Flushable flushable, boolean swallowIOException) throws IOException {
    try {
      flushable.flush();
    } catch (IOException e) {

    throwIf(closed);
    return options.contains(TestOption.AVAILABLE_ALWAYS_ZERO) ? 0 : in.available();
  }

  @Override
  public void close() throws IOException {
    closed = true;
    throwIf(CLOSE_THROWS);
    in.close();
  }

  private void throwIf(TestOption option) throws IOException {
    throwIf(options.contains(option));
  }

    /**
     * {@inheritDoc}
     *
     * @throws CIFSException if an error occurs closing the handle
     *
     * @see java.lang.AutoCloseable#close()
     */
    @Override
    void close() throws CIFSException;

    /**
     * Tests whether this file descriptor is open and valid.
     *
     * @return whether the FD is open and valid
     */
    boolean isOpen();

 *
 * <p><b>Warning:</b> The methods of {@code ForwardingList} forward <b>indiscriminately</b> to the
 * methods of the delegate. For example, overriding {@link #add} alone <b>will not</b> change the
 * behavior of {@link #addAll}, which can lead to unexpected behavior. In this case, you should
 * override {@code addAll} as well, either providing your own implementation, or delegating to the

 *
 * <p><b>Warning:</b> The methods of {@code ForwardingSortedMultiset} forward
 * <b>indiscriminately</b> to the methods of the delegate. For example, overriding {@link
 * #add(Object, int)} alone <b>will not</b> change the behavior of {@link #add(Object)}, which can
 * lead to unexpected behavior. In this case, you should override {@code add(Object)} as well,

        @Test
        @DisplayName("Should wipe key on close")
        void testCloseWipesKey() throws Exception {
            byte[] sessionKey = new byte[16];
            Arrays.fill(sessionKey, (byte) 0xBB);

            Smb2SigningDigest digest = new Smb2SigningDigest(sessionKey, Smb2Constants.SMB2_DIALECT_0202, null);

            // Close the digest
            digest.close();

            // Verify operations fail after close

                fos = null; // Successfully wrapped, no need to close explicitly
            } catch (final Exception e) {
                if (fos != null) {
                    try {
                        fos.close();
                    } catch (final IOException ioe) {
                        // Ignore close exception
                    }
                }
                if (newFile != null) {