Guava: Google Core Libraries for Java 32.1.2-jre · com.google.common.io.BaseEncoding

A binary encoding scheme for reversibly translating between byte sequences and printable ASCII strings. This class includes several constants for encoding schemes specified by RFC 4648. For example, the expression:

BaseEncoding.base32().encode("foo".getBytes(Charsets.US_ASCII))

returns the string "MZXW6===", and

byte[] decoded = BaseEncoding.base32().decode("MZXW6===");

...returns the ASCII bytes of the string "foo".

By default, BaseEncoding's behavior is relatively strict and in accordance with RFC 4648. Decoding rejects characters in the wrong case, though padding is optional. To modify encoding and decoding behavior, use configuration methods to obtain a new encoding with modified behavior:

BaseEncoding.base16().lowerCase().decode("deadbeef");

Warning

BaseEncoding instances are immutable. Invoking a configuration method has no effect on the receiving instance; you must store and use the new encoding instance it returns, instead.

// Do NOT do this
BaseEncoding hex = BaseEncoding.base16();
hex.lowerCase(); // does nothing!
return hex.decode("deadbeef"); // throws an IllegalArgumentException

It is guaranteed that encoding.decode(encoding.encode(x)) is always equal to x, but the reverse does not necessarily hold.

Encodings
Encoding	Alphabet	`char:byte` ratio	Default padding	Comments
`base16()`	0-9 A-F	2.00	N/A	Traditional hexadecimal. Defaults to upper case.
`base32()`	A-Z 2-7	1.60	=	Human-readable; no possibility of mixing up 0/O or 1/I. Defaults to upper case.
`base32Hex()`	0-9 A-V	1.60	=	"Numerical" base 32; extended from the traditional hex alphabet. Defaults to upper case.
`base64()`	A-Z a-z 0-9 + /	1.33	=
`base64Url()`	A-Z a-z 0-9 - _	1.33	=	Safe to use as filenames, or to pass in URLs without escaping

All instances of this class are immutable, so they may be stored safely as static constants.

Modifier and Type	Class and Description
private static class	BaseEncoding.Alphabet
pack-priv static class	BaseEncoding.Base16Encoding
pack-priv static class	BaseEncoding.Base64Encoding
public static class	BaseEncoding.DecodingException Exception indicating invalid base-encoded input encountered while decoding.
pack-priv static class	BaseEncoding.SeparatedBaseEncoding
pack-priv static class	BaseEncoding.StandardBaseEncoding

Modifier and Type	Field and Description
private static final BaseEncoding	BASE16
private static final BaseEncoding	BASE32
private static final BaseEncoding	BASE32_HEX
private static final BaseEncoding	BASE64
private static final BaseEncoding	BASE64_URL

Access	Constructor and Description
pack-priv	BaseEncoding()

Method Summary

Modifier and Type	Method and Description
public static BaseEncoding	base16() The "base16" encoding specified by RFC 4648 section 8, Base 16 Encoding.
public static BaseEncoding	base32() The "base32" encoding specified by RFC 4648 section 6, Base 32 Encoding.
public static BaseEncoding	base32Hex() The "base32hex" encoding specified by RFC 4648 section 7, Base 32 Encoding with Extended Hex Alphabet.
public static BaseEncoding	base64() The "base64" base encoding specified by RFC 4648 section 4, Base 64 Encoding.
public static BaseEncoding	base64Url() The "base64url" encoding specified by RFC 4648 section 5, Base 64 Encoding with URL and Filename Safe Alphabet, also sometimes referred to as the "web safe Base64." (This is the same as the base 64 encoding with URL and filename safe alphabet from RFC 3548.) The character `'='` is used for padding, but can be omitted or replaced.
public abstract boolean	canDecode(CharSequence chars) Determines whether the specified character sequence is a valid encoded string according to this encoding.
public final byte[]	decode(CharSequence chars) Decodes the specified character sequence, and returns the resulting `byte[]`.
pack-priv final byte[]	decodeChecked(CharSequence chars) Decodes the specified character sequence, and returns the resulting `byte[]`.
pack-priv abstract int	decodeTo(byte[] target, CharSequence chars)
public final ByteSource	decodingSource(CharSource encodedSource) Returns a `ByteSource` that reads base-encoded bytes from the specified `CharSource`.
public abstract InputStream	decodingStream(Reader reader) Returns an `InputStream` that decodes base-encoded input from the specified `Reader`.
public String	encode(byte[] bytes) Encodes the specified byte array, and returns the encoded `String`.
public final String	encode(byte[] bytes, int off, int len) Encodes the specified range of the specified byte array, and returns the encoded `String`.
pack-priv abstract void	encodeTo(Appendable target, byte[] bytes, int off, int len)
public final ByteSink	encodingSink(CharSink encodedSink) Returns a `ByteSink` that writes base-encoded bytes to the specified `CharSink`.
public abstract OutputStream	encodingStream(Writer writer) Returns an `OutputStream` that encodes bytes using this encoding into the specified `Writer`.
private static byte[]	extract(byte[] result, int length)
public abstract BaseEncoding	ignoreCase() Returns an encoding that behaves equivalently to this encoding, but decodes letters without regard to case.
pack-priv static Reader	ignoringReader(Reader delegate, String toIgnore)
public abstract BaseEncoding	lowerCase() Returns an encoding that behaves equivalently to this encoding, but encodes and decodes with lowercase letters.
pack-priv abstract int	maxDecodedSize(int chars)
pack-priv abstract int	maxEncodedSize(int bytes)
public abstract BaseEncoding	omitPadding() Returns an encoding that behaves equivalently to this encoding, but omits any padding characters as specified by RFC 4648 section 3.2, Padding of Encoded Data.
pack-priv static Appendable	separatingAppendable(Appendable delegate, String separator, int afterEveryChars)
pack-priv static Writer	separatingWriter(Writer delegate, String separator, int afterEveryChars)
pack-priv CharSequence	trimTrailingPadding(CharSequence chars)
public abstract BaseEncoding	upperCase() Returns an encoding that behaves equivalently to this encoding, but encodes and decodes with uppercase letters.
public abstract BaseEncoding	withPadChar(char padChar) Returns an encoding that behaves equivalently to this encoding, but uses an alternate character for padding.
public abstract BaseEncoding	withSeparator(String separator, int n) Returns an encoding that behaves equivalently to this encoding, but adds a separator string after every `n` characters.

Inherited from java.lang.Object:: clone equals finalize getClass hashCode notify notifyAll toString wait wait wait

public abstract Class BaseEncoding

Nested and Inner Type Summary

Field Summary

Constructor Summary

Method Summary