Class Base64

java.lang.Object
java.util.Base64
public final class Base64 extends Object
This class consists exclusively of static methods for obtaining encoders and decoders for the Base64 encoding scheme. The implementation of this class supports the following types of Base64 as specified in RFC 4648 and RFC 2045.
  • Basic

    Uses "The Base64 Alphabet" as specified in Table 1 of RFC 4648 and RFC 2045 for encoding and decoding operation. The encoder does not add any line feed (line separator) character. The decoder rejects data that contains characters outside the base64 alphabet.

  • URL and Filename safe

    Uses the "URL and Filename safe Base64 Alphabet" as specified in Table 2 of RFC 4648 for encoding and decoding. The encoder does not add any line feed (line separator) character. The decoder rejects data that contains characters outside the base64 alphabet.

  • MIME

    Uses "The Base64 Alphabet" as specified in Table 1 of RFC 2045 for encoding and decoding operation. The encoded output must be represented in lines of no more than 76 characters each and uses a carriage return '\r' followed immediately by a linefeed '\n' as the line separator. No line separator is added to the end of the encoded output. All line separators or other characters not found in the base64 alphabet table are ignored in decoding operation.

Unless otherwise noted, passing a null argument to a method of this class will cause a NullPointerException to be thrown.

Since:
1.8
External Specifications

  • Nested Class Summary

    Nested Classes
    Modifier and Type
    Class
    Description
    static class 
    Base64.Decoder
    This class implements a decoder for decoding byte data using the Base64 encoding scheme as specified in RFC 4648 and RFC 2045.
    static class 
    Base64.Encoder
    This class implements an encoder for encoding byte data using the Base64 encoding scheme as specified in RFC 4648 and RFC 2045.

  • Method Summary

    Modifier and Type
    Method
    Description
    static Base64.Decoder
    getDecoder()
    Returns a Base64.Decoder that decodes using the Basic type base64 encoding scheme.
    static Base64.Encoder
    getEncoder()
    Returns a Base64.Encoder that encodes using the Basic type base64 encoding scheme.
    static Base64.Decoder
    getMimeDecoder()
    Returns a Base64.Decoder that decodes using the MIME type base64 decoding scheme.
    static Base64.Encoder
    getMimeEncoder()
    Returns a Base64.Encoder that encodes using the MIME type base64 encoding scheme.
    static Base64.Encoder
    getMimeEncoder(int lineLength, byte[] lineSeparator)
    Returns a Base64.Encoder that encodes using the MIME type base64 encoding scheme with specified line length and line separators.
    static Base64.Decoder
    getUrlDecoder()
    Returns a Base64.Decoder that decodes using the URL and Filename safe type base64 encoding scheme.
    static Base64.Encoder
    getUrlEncoder()
    Returns a Base64.Encoder that encodes using the URL and Filename safe type base64 encoding scheme.

    Methods declared in class Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
    Modifier and Type
    Method
    Description
    protected Object
    clone()
    Answers a new instance of the same class as the receiver, whose slots have been filled in with the values in the slots of the receiver.
    boolean
    equals(Object o)
    Compares the argument to the receiver, and answers true if they represent the same object using a class specific comparison.
    protected void
    finalize()
    Deprecated, for removal: This API element is subject to removal in a future version.
    May cause performance issues, deadlocks and hangs.
    final Class<? extends Object>
    getClass()
    Answers the unique instance of java.lang.Class which represents the class of the receiver.
    int
    hashCode()
    Answers an integer hash code for the receiver.
    final void
    notify()
    Causes one thread which is waiting on the receiver to be made ready to run.
    final void
    notifyAll()
    Causes all threads which are waiting on the receiver to be made ready to run.
    String
    toString()
    Answers a string containing a concise, human-readable description of the receiver.
    final void
    wait()
    Causes the thread which sent this message to be made not ready to run pending some change in the receiver (as indicated by notify or notifyAll).
    final void
    wait(long time)
    Causes the thread which sent this message to be made not ready to run either pending some change in the receiver (as indicated by notify or notifyAll) or the expiration of the timeout.
    final void
    wait(long time, int frac)
    Causes the thread which sent this message to be made not ready to run either pending some change in the receiver (as indicated by notify or notifyAll) or the expiration of the timeout.

  • Method Details

    • getEncoder

      public static Base64.Encoder getEncoder()
      Returns a Base64.Encoder that encodes using the Basic type base64 encoding scheme.
      Returns:
      A Base64 encoder.

    • getUrlEncoder

      public static Base64.Encoder getUrlEncoder()
      Returns a Base64.Encoder that encodes using the URL and Filename safe type base64 encoding scheme.
      Returns:
      A Base64 encoder.

    • getMimeEncoder

      public static Base64.Encoder getMimeEncoder()
      Returns a Base64.Encoder that encodes using the MIME type base64 encoding scheme.
      Returns:
      A Base64 encoder.

    • getMimeEncoder

      public static Base64.Encoder getMimeEncoder(int lineLength, byte[] lineSeparator)
      Returns a Base64.Encoder that encodes using the MIME type base64 encoding scheme with specified line length and line separators.
      Parameters:
      lineLength - the length of each output line (rounded down to nearest multiple of 4). If the rounded down line length is not a positive value, the output will not be separated in lines
      lineSeparator - the line separator for each output line
      Returns:
      A Base64 encoder.
      Throws:
      IllegalArgumentException - if lineSeparator includes any character of "The Base64 Alphabet" as specified in Table 1 of RFC 2045.

    • getDecoder

      public static Base64.Decoder getDecoder()
      Returns a Base64.Decoder that decodes using the Basic type base64 encoding scheme.
      Returns:
      A Base64 decoder.

    • getUrlDecoder

      public static Base64.Decoder getUrlDecoder()
      Returns a Base64.Decoder that decodes using the URL and Filename safe type base64 encoding scheme.
      Returns:
      A Base64 decoder.

    • getMimeDecoder

      public static Base64.Decoder getMimeDecoder()
      Returns a Base64.Decoder that decodes using the MIME type base64 decoding scheme.
      Returns:
      A Base64 decoder.