java.lang.Object
org.sonatype.plexus.components.cipher.Base64

public class Base64 extends Object

Provides Base64 encoding and decoding as defined by RFC 2045.

This class implements section 6.8. Base64 Content-Transfer-Encoding from RFC 2045 Multipurpose Internet Mail Extensions (MIME) Part One: Format of Internet Message Bodies by Freed and Borenstein.

Since:
1.0-dev
See Also:
  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    private static final byte[]
    Contains the Base64 values 0 through 63 accessed by using character encodings as indices.
    (package private) static final int
    The base length.
    (package private) static final byte[]
    Chunk separator per RFC 2045 section 2.1.
    (package private) static final int
    Chunk size per RFC 2045 section 6.8.
    (package private) static final int
    Used to calculate the number of bits in a byte.
    (package private) static final int
    Used to get the number of Quadruples.
    private static final byte[]
    Contains the Base64 encodings A through Z, followed by a through z, followed by 0 through 9, followed by +, and /.
    (package private) static final int
    Lookup length.
    (package private) static final byte
    Byte used to pad output.
    (package private) static final int
    Used to test the sign of a byte.
    (package private) static final int
    Used when encoding something which has fewer than 24 bits.
    (package private) static final int
    Used to determine how many bits data contains.
  • Constructor Summary

    Constructors
    Constructor
    Description
     
  • Method Summary

    Modifier and Type
    Method
    Description
    byte[]
    decode(byte[] pArray)
    Decodes a byte[] containing containing characters in the Base64 alphabet.
    decode(Object pObject)
    Decodes an Object using the base64 algorithm.
    static byte[]
    decodeBase64(byte[] base64Data)
    Decodes Base64 data into octects
    (package private) static byte[]
    discardNonBase64(byte[] data)
    Discards any characters outside of the base64 alphabet, per the requirements on page 25 of RFC 2045 - "Any characters outside of the base64 alphabet are to be ignored in base64 encoded data."
    (package private) static byte[]
    discardWhitespace(byte[] data)
    Discards any whitespace from a base-64 encoded block.
    byte[]
    encode(byte[] pArray)
    Encodes a byte[] containing binary data, into a byte[] containing characters in the Base64 alphabet.
    encode(Object pObject)
    Encodes an Object using the base64 algorithm.
    static byte[]
    encodeBase64(byte[] binaryData)
    Encodes binary data using the base64 algorithm but does not chunk the output.
    static byte[]
    encodeBase64(byte[] binaryData, boolean isChunked)
    Encodes binary data using the base64 algorithm, optionally chunking the output into 76 character blocks.
    static byte[]
    encodeBase64Chunked(byte[] binaryData)
    Encodes binary data using the base64 algorithm and chunks the encoded output into 76 character blocks
    static boolean
    isArrayByteBase64(byte[] arrayOctect)
    Tests a given byte array to see if it contains only valid characters within the Base64 alphabet.
    static boolean
    isBase64(byte b)
    Returns whether or not the octect is in the base 64 alphabet.

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
  • Field Details

    • CHUNK_SIZE

      static final int CHUNK_SIZE
      Chunk size per RFC 2045 section 6.8.

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

      See Also:
    • CHUNK_SEPARATOR

      static final byte[] CHUNK_SEPARATOR
      Chunk separator per RFC 2045 section 2.1.
      See Also:
    • BASELENGTH

      static final int BASELENGTH
      The base length.
      See Also:
    • LOOKUPLENGTH

      static final int LOOKUPLENGTH
      Lookup length.
      See Also:
    • EIGHTBIT

      static final int EIGHTBIT
      Used to calculate the number of bits in a byte.
      See Also:
    • SIXTEENBIT

      static final int SIXTEENBIT
      Used when encoding something which has fewer than 24 bits.
      See Also:
    • TWENTYFOURBITGROUP

      static final int TWENTYFOURBITGROUP
      Used to determine how many bits data contains.
      See Also:
    • FOURBYTE

      static final int FOURBYTE
      Used to get the number of Quadruples.
      See Also:
    • SIGN

      static final int SIGN
      Used to test the sign of a byte.
      See Also:
    • PAD

      static final byte PAD
      Byte used to pad output.
      See Also:
    • base64Alphabet

      private static final byte[] base64Alphabet
      Contains the Base64 values 0 through 63 accessed by using character encodings as indices.

      For example, base64Alphabet['+'] returns 62.

      The value of undefined encodings is -1.

    • lookUpBase64Alphabet

      private static final byte[] lookUpBase64Alphabet

      Contains the Base64 encodings A through Z, followed by a through z, followed by 0 through 9, followed by +, and /.

      This array is accessed by using character values as indices.

      For example, lookUpBase64Alphabet[62] returns '+'.

  • Constructor Details

    • Base64

      public Base64()
  • Method Details

    • isBase64

      public static boolean isBase64(byte b)
      Returns whether or not the octect is in the base 64 alphabet.
      Parameters:
      b - The value to test
      Returns:
      true if the value is defined in the the base 64 alphabet, false otherwise.
    • isArrayByteBase64

      public static boolean isArrayByteBase64(byte[] arrayOctect)
      Tests a given byte array to see if it contains only valid characters within the Base64 alphabet.
      Parameters:
      arrayOctect - byte array to test
      Returns:
      true if all bytes are valid characters in the Base64 alphabet or if the byte array is empty; false, otherwise
    • encodeBase64

      public static byte[] encodeBase64(byte[] binaryData)
      Encodes binary data using the base64 algorithm but does not chunk the output.
      Parameters:
      binaryData - binary data to encode
      Returns:
      Base64 characters
    • encodeBase64Chunked

      public static byte[] encodeBase64Chunked(byte[] binaryData)
      Encodes binary data using the base64 algorithm and chunks the encoded output into 76 character blocks
      Parameters:
      binaryData - binary data to encode
      Returns:
      Base64 characters chunked in 76 character blocks
    • decode

      public Object decode(Object pObject) throws IllegalArgumentException
      Decodes an Object using the base64 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[].
      Parameters:
      pObject - Object to decode
      Returns:
      An object (of type byte[]) containing the binary data which corresponds to the byte[] supplied.
      Throws:
      IllegalArgumentException - if the parameter supplied is not of type byte[]
    • decode

      public byte[] decode(byte[] pArray)
      Decodes a byte[] containing containing characters in the Base64 alphabet.
      Parameters:
      pArray - A byte array containing Base64 character data
      Returns:
      a byte array containing binary data
    • encodeBase64

      public static byte[] encodeBase64(byte[] binaryData, boolean isChunked)
      Encodes binary data using the base64 algorithm, optionally chunking the output into 76 character blocks.
      Parameters:
      binaryData - Array containing binary data to encode.
      isChunked - if true this encoder will chunk the base64 output into 76 character blocks
      Returns:
      Base64-encoded data.
    • decodeBase64

      public static byte[] decodeBase64(byte[] base64Data)
      Decodes Base64 data into octects
      Parameters:
      base64Data - Byte array containing Base64 data
      Returns:
      Array containing decoded data.
    • discardWhitespace

      static byte[] discardWhitespace(byte[] data)
      Discards any whitespace from a base-64 encoded block.
      Parameters:
      data - The base-64 encoded data to discard the whitespace from.
      Returns:
      The data, less whitespace (see RFC 2045).
    • discardNonBase64

      static byte[] discardNonBase64(byte[] data)
      Discards any characters outside of the base64 alphabet, per the requirements on page 25 of RFC 2045 - "Any characters outside of the base64 alphabet are to be ignored in base64 encoded data."
      Parameters:
      data - The base-64 encoded data to groom
      Returns:
      The data, less non-base64 characters (see RFC 2045).
    • encode

      public Object encode(Object pObject) throws IllegalArgumentException
      Encodes an Object using the base64 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[].
      Parameters:
      pObject - Object to encode
      Returns:
      An object (of type byte[]) containing the base64 encoded data which corresponds to the byte[] supplied.
      Throws:
      IllegalArgumentException - 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 Base64 alphabet.
      Parameters:
      pArray - a byte array containing binary data
      Returns:
      A byte array containing only Base64 character data