Class Base64Variant


  • public final class Base64Variant
    extends Object
    Abstract base class used to define specific details of which variant of Base64 encoding/decoding is to be used. Although there is somewhat standard basic version (so-called "MIME Base64"), other variants exists, see Base64 Wikipedia entry for details.
    Since:
    0.9.3
    Author:
    Tatu Saloranta
    • Field Detail

      • BASE64_VALUE_INVALID

        public static final int BASE64_VALUE_INVALID
        Marker used to denote ascii characters that do not correspond to a 6-bit value (in this variant), and is not used as a padding character.
        See Also:
        Constant Field Values
      • BASE64_VALUE_PADDING

        public static final int BASE64_VALUE_PADDING
        Marker used to denote ascii character (in decoding table) that is the padding character using this variant (if any).
        See Also:
        Constant Field Values
    • Constructor Detail

      • Base64Variant

        public Base64Variant​(String name,
                             String base64Alphabet,
                             boolean usesPadding,
                             char paddingChar,
                             int maxLineLength)
      • Base64Variant

        public Base64Variant​(Base64Variant base,
                             String name,
                             int maxLineLength)
        "Copy constructor" that can be used when the base alphabet is identical to one used by another variant except for the maximum line length (and obviously, name).
      • Base64Variant

        public Base64Variant​(Base64Variant base,
                             String name,
                             boolean usesPadding,
                             char paddingChar,
                             int maxLineLength)
        "Copy constructor" that can be used when the base alphabet is identical to one used by another variant, but other details (padding, maximum line length) differ
    • Method Detail

      • getName

        public String getName()
      • usesPadding

        public boolean usesPadding()
      • usesPaddingChar

        public boolean usesPaddingChar​(char c)
      • usesPaddingChar

        public boolean usesPaddingChar​(int ch)
      • getPaddingChar

        public char getPaddingChar()
      • getPaddingByte

        public byte getPaddingByte()
      • getMaxLineLength

        public int getMaxLineLength()
      • decodeBase64Char

        public int decodeBase64Char​(char c)
        Returns:
        6-bit decoded value, if valid character;
      • decodeBase64Char

        public int decodeBase64Char​(int ch)
      • decodeBase64Byte

        public int decodeBase64Byte​(byte b)
      • encodeBase64BitsAsChar

        public char encodeBase64BitsAsChar​(int value)
      • encodeBase64Chunk

        public int encodeBase64Chunk​(int b24,
                                     char[] buffer,
                                     int ptr)
        Method that encodes given right-aligned (LSB) 24-bit value into 4 base64 characters, stored in given result buffer.
      • encodeBase64Chunk

        public void encodeBase64Chunk​(StringBuilder sb,
                                      int b24)
      • encodeBase64Partial

        public int encodeBase64Partial​(int bits,
                                       int outputBytes,
                                       char[] buffer,
                                       int outPtr)
        Method that outputs partial chunk (which only encodes one or two bytes of data). Data given is still aligned same as if it as full data; that is, missing data is at the "right end" (LSB) of int.
        Parameters:
        outputBytes - Number of encoded bytes included (either 1 or 2)
      • encodeBase64Partial

        public void encodeBase64Partial​(StringBuilder sb,
                                        int bits,
                                        int outputBytes)
      • encodeBase64BitsAsByte

        public byte encodeBase64BitsAsByte​(int value)
      • encodeBase64Chunk

        public int encodeBase64Chunk​(int b24,
                                     byte[] buffer,
                                     int ptr)
        Method that encodes given right-aligned (LSB) 24-bit value into 4 base64 bytes (ascii), stored in given result buffer.
      • encodeBase64Partial

        public int encodeBase64Partial​(int bits,
                                       int outputBytes,
                                       byte[] buffer,
                                       int outPtr)
        Method that outputs partial chunk (which only encodes one or two bytes of data). Data given is still aligned same as if it as full data; that is, missing data is at the "right end" (LSB) of int.
        Parameters:
        outputBytes - Number of encoded bytes included (either 1 or 2)
      • encode

        public String encode​(byte[] input)
        Convenience method for converting given byte array as base64 encoded String using this variant's settings. Resulting value is "raw", that is, not enclosed in double-quotes.
        Parameters:
        input - Byte array to encode
        Since:
        1.6
      • encode

        public String encode​(byte[] input,
                             boolean addQuotes)
        Convenience method for converting given byte array as base64 encoded String using this variant's settings, optionally enclosed in double-quotes.
        Parameters:
        input - Byte array to encode
        addQuotes - Whether to surround resulting value in double quotes or not
        Since:
        1.6