BaseNCodec (Apache Tomcat 9.0.111 API Documentation)
Description: declaration: package: org.apache.tomcat.util.codec.binary, class: BaseNCodec

# Class BaseNCodec

java.lang.Object
org.apache.tomcat.util.codec.binary.BaseNCodec

Direct Known Subclasses:
  `Base64`

@Deprecated public abstract class BaseNCodec extends Object
Deprecated.
Unused. This class will be removed in Tomcat 11 onwards.
Abstract superclass for Base-N encoders and decoders.

This class is thread-safe.

- ## Field Summary

  Fields
  Modifier and Type
  Field
  Description
  `protected final int`
  `lineLength`
  Deprecated.
  Chunksize for encoding.
  `protected static final int`
  `MASK_8BITS`
  Deprecated.
  Mask used to extract 8 bits, used in decoding bytes
  `static final int`
  `MIME_CHUNK_SIZE`
  Deprecated.
  MIME chunk size per RFC 2045 section 6.8.
  `protected final byte`
  `pad`
  Deprecated.
  Pad byte.
  `protected static final byte`
  `PAD_DEFAULT`
  Deprecated.
  Byte used to pad output.
  `protected static final StringManager`
  `sm`
  Deprecated.

- ## Constructor Summary

  Constructors
  Modifier
  Constructor
  Description
  `protected`
  `BaseNCodec(int unencodedBlockSize, int encodedBlockSize, int lineLength, int chunkSeparatorLength)`
  Deprecated.
  Note `lineLength` is rounded down to the nearest multiple of the encoded block size.
  `protected`
  `BaseNCodec(int unencodedBlockSize, int encodedBlockSize, int lineLength, int chunkSeparatorLength, byte pad)`
  Deprecated.
  Note `lineLength` is rounded down to the nearest multiple of the encoded block size.

- ## Method Summary

  Modifier and Type
  Method
  Description
  `protected boolean`
  `containsAlphabetOrPad(byte[] arrayOctet)`
  Deprecated.
  Tests a given byte array to see if it contains any characters within the alphabet or PAD.
  `byte[]`
  `decode(byte[] pArray)`
  Deprecated.
  Decodes a byte[] containing characters in the Base-N alphabet.
  `byte[]`
  `decode(byte[] pArray, int off, int len)`
  Deprecated.
  `byte[]`
  `decode(String pArray)`
  Deprecated.
  Decodes a String containing characters in the Base-N alphabet.
  `byte[]`
  `encode(byte[] pArray)`
  Deprecated.
  Encodes a byte[] containing binary data, into a byte[] containing characters in the alphabet.
  `byte[]`
  `encode(byte[] pArray, int offset, int length)`
  Deprecated.
  Encodes a byte[] containing binary data, into a byte[] containing characters in the alphabet.
  `String`
  `encodeAsString(byte[] pArray)`
  Deprecated.
  Encodes a byte[] containing binary data, into a String containing characters in the appropriate alphabet.
  `protected byte[]`
  `ensureBufferSize(int size, org.apache.tomcat.util.codec.binary.BaseNCodec.Context context)`
  Deprecated.
  Ensure that the buffer has room for `size` bytes
  `protected int`
  `getDefaultBufferSize()`
  Deprecated.
  Gets the default buffer size.
  `long`
  `getEncodedLength(byte[] pArray)`
  Deprecated.
  Calculates the amount of space needed to encode the supplied array.
  `protected abstract boolean`
  `isInAlphabet(byte value)`
  Deprecated.
  Returns whether or not the `octet` is in the current alphabet.

  ### Methods inherited from class Object

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

- ## Field Details

  - ### sm

    protected static final StringManager sm
    Deprecated.

  - ### MIME_CHUNK_SIZE

    public static final int MIME_CHUNK_SIZE
    Deprecated.
    MIME chunk size per RFC 2045 section 6.8.

    The 76 character limit does not count the trailing CRLF, but counts all other characters, including any equal signs.

    See Also:
      - RFC 2045 section 6.8
      - Constant Field Values

  - ### MASK_8BITS

    protected static final int MASK_8BITS
    Deprecated.
    Mask used to extract 8 bits, used in decoding bytes
    See Also:
      - Constant Field Values

  - ### PAD_DEFAULT

    protected static final byte PAD_DEFAULT
    Deprecated.
    Byte used to pad output.
    See Also:
      - Constant Field Values

  - ### pad

    protected final byte pad
    Deprecated.
    Pad byte. Instance variable just in case it needs to vary later.

  - ### lineLength

    protected final int lineLength
    Deprecated.
    Chunksize for encoding. Not used when decoding. A value of zero or less implies no chunking of the encoded data. Rounded down to the nearest multiple of encodedBlockSize.

- ## Constructor Details

  - ### BaseNCodec

    protected BaseNCodec(int unencodedBlockSize, int encodedBlockSize, int lineLength, int chunkSeparatorLength)
    Deprecated.
    Note `lineLength` is rounded down to the nearest multiple of the encoded block size. If `chunkSeparatorLength` is zero, then chunking is disabled.
    Parameters:
      `unencodedBlockSize` - the size of an unencoded block (e.g. Base64 = 3)
      `encodedBlockSize` - the size of an encoded block (e.g. Base64 = 4)
      `lineLength` - if > 0, use chunking with a length `lineLength`
      `chunkSeparatorLength` - the chunk separator length, if relevant

  - ### BaseNCodec

    protected BaseNCodec(int unencodedBlockSize, int encodedBlockSize, int lineLength, int chunkSeparatorLength, byte pad)
    Deprecated.
    Note `lineLength` is rounded down to the nearest multiple of the encoded block size. If `chunkSeparatorLength` is zero, then chunking is disabled.
    Parameters:
      `unencodedBlockSize` - the size of an unencoded block (e.g. Base64 = 3)
      `encodedBlockSize` - the size of an encoded block (e.g. Base64 = 4)
      `lineLength` - if > 0, use chunking with a length `lineLength`
      `chunkSeparatorLength` - the chunk separator length, if relevant
      `pad` - byte used as padding byte.

- ## Method Details

  - ### containsAlphabetOrPad

    protected boolean containsAlphabetOrPad(byte[] arrayOctet)
    Deprecated.
    Tests a given byte array to see if it contains any characters within the alphabet or PAD. Intended for use in checking line-ending arrays
    Parameters:
      `arrayOctet` - byte array to test
    Returns:
      `true` if any byte is a valid character in the alphabet or PAD; `false` otherwise

  - ### decode

    public byte[] decode(byte[] pArray)
    Deprecated.
    Decodes a byte[] containing characters in the Base-N alphabet.
    Parameters:
      `pArray` - A byte array containing Base-N character data
    Returns:
      a byte array containing binary data

  - ### decode

    public byte[] decode(byte[] pArray, int off, int len)
    Deprecated.

  - ### decode

    public byte[] decode(String pArray)
    Deprecated.
    Decodes a String containing characters in the Base-N alphabet.
    Parameters:
      `pArray` - A String containing Base-N character data
    Returns:
      a byte array containing binary data

  - ### encode

    public byte[] encode(byte[] pArray)
    Deprecated.
    Encodes a byte[] containing binary data, into a byte[] containing characters in the alphabet.
    Parameters:
      `pArray` - a byte array containing binary data
    Returns:
      A byte array containing only the base N alphabetic character data

  - ### encode

    public byte[] encode(byte[] pArray, int offset, int length)
    Deprecated.
    Encodes a byte[] containing binary data, into a byte[] containing characters in the alphabet.
    Parameters:
      `pArray` - a byte array containing binary data
      `offset` - initial offset of the subarray.
      `length` - length of the subarray.
    Returns:
      A byte array containing only the base N alphabetic character data
    Since:
      1.11

  - ### encodeAsString

    public String encodeAsString(byte[] pArray)
    Deprecated.
    Encodes a byte[] containing binary data, into a String containing characters in the appropriate alphabet. Uses UTF8 encoding.
    Parameters:
      `pArray` - a byte array containing binary data
    Returns:
      String containing only character data in the appropriate alphabet.
    Since:
      1.5

  - ### ensureBufferSize

    protected byte[] ensureBufferSize(int size, org.apache.tomcat.util.codec.binary.BaseNCodec.Context context)
    Deprecated.
    Ensure that the buffer has room for `size` bytes
    Parameters:
      `size` - minimum spare space required
      `context` - the context to be used
    Returns:
      the buffer

  - ### getDefaultBufferSize

    protected int getDefaultBufferSize()
    Deprecated.
    Gets the default buffer size. Can be overridden.
    Returns:
      the default buffer size.

  - ### getEncodedLength

    public long getEncodedLength(byte[] pArray)
    Deprecated.
    Calculates the amount of space needed to encode the supplied array.
    Parameters:
      `pArray` - byte[] array which will later be encoded
    Returns:
      amount of space needed to encode the supplied array. Returns a long since a max-len array will require > Integer.MAX_VALUE

  - ### isInAlphabet

    protected abstract boolean isInAlphabet(byte value)
    Deprecated.
    Returns whether or not the `octet` is in the current alphabet. Does not allow whitespace or pad.
    Parameters:
      `value` - The value to test
    Returns:
      `true` if the value is defined in the current alphabet, `false` otherwise.