NullCipher (Java Platform SE 8 )
Keywords: javax.crypto.NullCipher class
Date: 2026-07-22

compact1, compact2, compact3
javax.crypto

## Class NullCipher

- java.lang.Object
- - javax.crypto.Cipher
  - - javax.crypto.NullCipher

-     public class NullCipher
      extends Cipher

  The NullCipher class is a class that provides an "identity cipher" -- one that does not transform the plain text. As a consequence, the ciphertext is identical to the plaintext. All initialization methods do nothing, while the blocksize is set to 1 byte.
  Since:
    1.4

- - ### Field Summary

    - ### Fields inherited from class javax.crypto.Cipher

      `DECRYPT_MODE, ENCRYPT_MODE, PRIVATE_KEY, PUBLIC_KEY, SECRET_KEY, UNWRAP_MODE, WRAP_MODE`

  - ### Constructor Summary

    Constructors
    Constructor and Description
    `NullCipher()` Creates a NullCipher object.

  - ### Method Summary

    - ### Methods inherited from class javax.crypto.Cipher

      `doFinal, doFinal, doFinal, doFinal, doFinal, doFinal, doFinal, getAlgorithm, getBlockSize, getExemptionMechanism, getInstance, getInstance, getInstance, getIV, getMaxAllowedKeyLength, getMaxAllowedParameterSpec, getOutputSize, getParameters, getProvider, init, init, init, init, init, init, init, init, unwrap, update, update, update, update, update, updateAAD, updateAAD, updateAAD, wrap`

    - ### Methods inherited from class java.lang.Object

      `clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

- - ### Constructor Detail

    - #### NullCipher

          public NullCipher()

      Creates a NullCipher object.

Submit a bug or feature
For further API reference and developer documentation, see Java SE Documentation. That documentation contains more detailed, developer-targeted descriptions, with conceptual overviews, definitions of terms, workarounds, and working code examples.
Copyright © 1993, 2026, Oracle and/or its affiliates. All rights reserved. Use is subject to license terms. Also see the documentation redistribution policy.