Base64

public class Base64
extends Object

java.lang.Object
   ↳ java.util.Base64


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.

Summary

Nested classes

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. 

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. 

Public methods

static Base64.Decoder getDecoder()

Returns a Decoder that decodes using the Basic type base64 encoding scheme.

static Base64.Encoder getEncoder()

Returns a Encoder that encodes using the Basic type base64 encoding scheme.

static Base64.Decoder getMimeDecoder()

Returns a Decoder that decodes using the MIME type base64 decoding scheme.

static Base64.Encoder getMimeEncoder()

Returns a Encoder that encodes using the MIME type base64 encoding scheme.

static Base64.Encoder getMimeEncoder(int lineLength, byte[] lineSeparator)

Returns a Encoder that encodes using the MIME type base64 encoding scheme with specified line length and line separators.

static Base64.Decoder getUrlDecoder()

Returns a Decoder that decodes using the URL and Filename safe type base64 encoding scheme.

static Base64.Encoder getUrlEncoder()

Returns a Encoder that encodes using the URL and Filename safe type base64 encoding scheme.

Inherited methods

Object clone()

Creates and returns a copy of this object.

boolean equals(Object obj)

Indicates whether some other object is "equal to" this one.

void finalize()

Called by the garbage collector on an object when garbage collection determines that there are no more references to the object.

final Class<?> getClass()

Returns the runtime class of this Object.

int hashCode()

Returns a hash code value for the object.

final void notify()

Wakes up a single thread that is waiting on this object's monitor.

final void notifyAll()

Wakes up all threads that are waiting on this object's monitor.

String toString()

Returns a string representation of the object.

final void wait(long timeoutMillis, int nanos)

Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.

final void wait(long timeoutMillis)

Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.

final void wait()

Causes the current thread to wait until it is awakened, typically by being notified or interrupted.

Public methods

getDecoder

Added in API level 26
public static Base64.Decoder getDecoder ()

Returns a Decoder that decodes using the Basic type base64 encoding scheme.

Returns
Base64.Decoder A Base64 decoder.

getEncoder

Added in API level 26
public static Base64.Encoder getEncoder ()

Returns a Encoder that encodes using the Basic type base64 encoding scheme.

Returns
Base64.Encoder A Base64 encoder.

getMimeDecoder

Added in API level 26
public static Base64.Decoder getMimeDecoder ()

Returns a Decoder that decodes using the MIME type base64 decoding scheme.

Returns
Base64.Decoder A Base64 decoder.

getMimeEncoder

Added in API level 26
public static Base64.Encoder getMimeEncoder ()

Returns a Encoder that encodes using the MIME type base64 encoding scheme.

Returns
Base64.Encoder A Base64 encoder.

getMimeEncoder

Added in API level 26
public static Base64.Encoder getMimeEncoder (int lineLength, 
                byte[] lineSeparator)

Returns a Encoder that encodes using the MIME type base64 encoding scheme with specified line length and line separators.

Parameters
lineLength int: 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 byte: the line separator for each output line

Returns
Base64.Encoder A Base64 encoder.

Throws
IllegalArgumentException if lineSeparator includes any character of "The Base64 Alphabet" as specified in Table 1 of RFC 2045.

getUrlDecoder

Added in API level 26
public static Base64.Decoder getUrlDecoder ()

Returns a Decoder that decodes using the URL and Filename safe type base64 encoding scheme.

Returns
Base64.Decoder A Base64 decoder.

getUrlEncoder

Added in API level 26
public static Base64.Encoder getUrlEncoder ()

Returns a Encoder that encodes using the URL and Filename safe type base64 encoding scheme.

Returns
Base64.Encoder A Base64 encoder.