java.lang.Object

org.apache.tomcat.util.codec.binary.BaseNCodec

All Implemented Interfaces:: BinaryDecoder, BinaryEncoder, Decoder, Encoder

Direct Known Subclasses:: Base64

public abstract class BaseNCodec extends Object implements BinaryEncoder, BinaryDecoder

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

Chunksize for encoding.

protected static final int

MASK_8BITS

Mask used to extract 8 bits, used in decoding bytes

static final int

MIME_CHUNK_SIZE

MIME chunk size per RFC 2045 section 6.8.

protected final byte

pad

Pad byte.

protected static final byte

PAD_DEFAULT

Byte used to pad output.

static final int

PEM_CHUNK_SIZE

PEM chunk size per RFC 1421 section 4.3.2.4.

protected static final StringManager

sm
Constructor Summary

Constructors

Modifier

Constructor

Description

protected

BaseNCodec(int unencodedBlockSize, int encodedBlockSize, int lineLength, int chunkSeparatorLength)

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)

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)

Tests a given byte array to see if it contains any characters within the alphabet or PAD.

byte[]

decode(byte[] pArray)

Decodes a byte[] containing characters in the Base-N alphabet.

byte[]

decode(byte[] pArray, int off, int len)

Object

decode(Object obj)

Deprecated.
This unused method will be removed in Tomcat 9

byte[]

decode(String pArray)

Decodes a String containing characters in the Base-N alphabet.

byte[]

encode(byte[] pArray)

Encodes a byte[] containing binary data, into a byte[] containing characters in the alphabet.

byte[]

encode(byte[] pArray, int offset, int length)

Encodes a byte[] containing binary data, into a byte[] containing characters in the alphabet.

Object

encode(Object obj)

Deprecated.
This unused method will be removed in Tomcat 9

String

encodeAsString(byte[] pArray)

Encodes a byte[] containing binary data, into a String containing characters in the appropriate alphabet.

String

encodeToString(byte[] pArray)

Encodes a byte[] containing binary data, into a String containing characters in the Base-N alphabet.

protected byte[]

ensureBufferSize(int size, org.apache.tomcat.util.codec.binary.BaseNCodec.Context context)

Ensure that the buffer has room for size bytes

static byte[]

getChunkSeparator()

Gets a copy of the chunk separator per RFC 2045 section 2.1.

protected int

getDefaultBufferSize()

Get the default buffer size.

long

getEncodedLength(byte[] pArray)

Calculates the amount of space needed to encode the supplied array.

protected abstract boolean

isInAlphabet(byte value)

Returns whether or not the octet is in the current alphabet.

boolean

isInAlphabet(byte[] arrayOctet, boolean allowWSPad)

Tests a given byte array to see if it contains only valid characters within the alphabet.

boolean

isInAlphabet(String basen)

Tests a given String to see if it contains only valid characters within the alphabet.

protected static boolean

isWhiteSpace(byte byteToCheck)

Checks if a byte value is whitespace or not.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details
- sm
  
  protected static final StringManager sm
- MIME_CHUNK_SIZE
  
  public static final int MIME_CHUNK_SIZE
  
  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
- PEM_CHUNK_SIZE
  
  public static final int PEM_CHUNK_SIZE
  
  PEM chunk size per RFC 1421 section 4.3.2.4.
  The 64 character limit does not count the trailing CRLF, but counts all other characters, including any equal signs.
  See Also:
  
  RFC 1421 section 4.3.2.4
  
  Constant Field Values
- MASK_8BITS
  
  protected static final int MASK_8BITS
  
  Mask used to extract 8 bits, used in decoding bytes
  See Also:
  
  Constant Field Values
- PAD_DEFAULT
  
  protected static final byte PAD_DEFAULT
  
  Byte used to pad output.
  See Also:
  
  Constant Field Values
- pad
  
  protected final byte pad
  
  Pad byte. Instance variable just in case it needs to vary later.
- lineLength
  
  protected final int lineLength
  
  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)
  
  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)
  
  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
- getChunkSeparator
  
  public static byte[] getChunkSeparator()
  
  Gets a copy of the chunk separator per RFC 2045 section 2.1.
  Returns:
  
  the chunk separator
  
  Since:
  
  1.15
  
  See Also:
  
  RFC 2045 section 2.1
- isWhiteSpace
  
  protected static boolean isWhiteSpace(byte byteToCheck)
  
  Checks if a byte value is whitespace or not. Whitespace is taken to mean: space, tab, CR, LF
  
  Parameters:
  
  byteToCheck - the byte to check
  
  Returns:
  
  true if byte is whitespace, false otherwise
- containsAlphabetOrPad
  
  protected boolean containsAlphabetOrPad(byte[] arrayOctet)
  
  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)
  
  Decodes a byte[] containing characters in the Base-N alphabet.
  
  Specified by:
  
  decode in interface BinaryDecoder
  
  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)
- decode
  
  public byte[] decode(String pArray)
  
  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
- decode
  
  @Deprecated public Object decode(Object obj) throws DecoderException
  
  Deprecated.
  This unused method will be removed in Tomcat 9
  
  Decodes an Object using the Base-N algorithm. This method is provided in order to satisfy the requirements of the Decoder interface, and will throw a DecoderException if the supplied object is not of type byte[] or String.
  
  Specified by:
  
  decode in interface Decoder
  
  Parameters:
  
  obj - Object to decode
  
  Returns:
  
  An object (of type byte[]) containing the binary data which corresponds to the byte[] or String supplied.
  
  Throws:
  
  DecoderException - if the parameter supplied is not of type byte[]
- encode
  
  public byte[] encode(byte[] pArray)
  
  Encodes a byte[] containing binary data, into a byte[] containing characters in the alphabet.
  
  Specified by:
  
  encode in interface BinaryEncoder
  
  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)
  
  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)
  
  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 This is a duplicate of encodeToString(byte[]); it was merged during refactoring.
- encode
  
  @Deprecated public Object encode(Object obj) throws EncoderException
  
  Deprecated.
  This unused method will be removed in Tomcat 9
  
  Encodes an Object using the Base-N algorithm. This method is provided in order to satisfy the requirements of the Encoder interface, and will throw an EncoderException if the supplied object is not of type byte[].
  
  Specified by:
  
  encode in interface Encoder
  
  Parameters:
  
  obj - Object to encode
  
  Returns:
  
  An object (of type byte[]) containing the Base-N encoded data which corresponds to the byte[] supplied.
  
  Throws:
  
  EncoderException - if the parameter supplied is not of type byte[]
- encodeToString
  
  public String encodeToString(byte[] pArray)
  
  Encodes a byte[] containing binary data, into a String containing characters in the Base-N alphabet. Uses UTF8 encoding.
  
  Parameters:
  
  pArray - a byte array containing binary data
  
  Returns:
  
  A String containing only Base-N character data
- ensureBufferSize
  
  protected byte[] ensureBufferSize(int size, org.apache.tomcat.util.codec.binary.BaseNCodec.Context context)
  
  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()
  
  Get the default buffer size. Can be overridden.
  
  Returns:
  
  the default buffer size.
- getEncodedLength
  
  public long getEncodedLength(byte[] pArray)
  
  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)
  
  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.
- isInAlphabet
  
  public boolean isInAlphabet(byte[] arrayOctet, boolean allowWSPad)
  
  Tests a given byte array to see if it contains only valid characters within the alphabet. The method optionally treats whitespace and pad as valid.
  
  Parameters:
  
  arrayOctet - byte array to test
  
  allowWSPad - if true, then whitespace and PAD are also allowed
  
  Returns:
  
  true if all bytes are valid characters in the alphabet or if the byte array is empty; false, otherwise
- isInAlphabet
  
  public boolean isInAlphabet(String basen)
  
  Tests a given String to see if it contains only valid characters within the alphabet. The method treats whitespace and PAD as valid.
  Parameters:
  
  basen - String to test
  
  Returns:
  
  true if all characters in the String are valid characters in the alphabet or if the String is empty; false, otherwise
  
  See Also:
  
  isInAlphabet(byte[], boolean)

Class BaseNCodec

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Details

sm

MIME_CHUNK_SIZE

PEM_CHUNK_SIZE

MASK_8BITS

PAD_DEFAULT

pad

lineLength

Constructor Details

BaseNCodec

BaseNCodec

Method Details

getChunkSeparator

isWhiteSpace

containsAlphabetOrPad

decode

decode

decode

decode

encode

encode

encodeAsString

encode

encodeToString

ensureBufferSize

getDefaultBufferSize

getEncodedLength

isInAlphabet

isInAlphabet

isInAlphabet