org.springframework.util

Class Base64Utils

java.lang.Object

org.springframework.util.Base64Utils

public abstract class Base64Utils
extends java.lang.Object

A simple utility class for Base64 encoding and decoding.

Adapts to either Java 8's Base64 class or Apache Commons Codec's org.apache.commons.codec.binary.Base64 class. With neither Java 8 nor Commons Codec present, encode(byte[])/decode(byte[]) calls will throw an IllegalStateException. However, as of Spring 4.2, encodeToString(byte[]) and decodeFromString(java.lang.String) will nevertheless work since they can delegate to the JAXB DatatypeConverter as a fallback. However, this does not apply when using the "UrlSafe" methods for RFC 4648 "URL and Filename Safe Alphabet"; a delegate is required.

Note: Apache Commons Codec does not add padding (=) when encoding with the URL and Filename Safe Alphabet.

Since:

4.1

Author:

Juergen Hoeller, Gary Russell

See Also:

Base64, org.apache.commons.codec.binary.Base64, DatatypeConverter.printBase64Binary(byte[]), DatatypeConverter.parseBase64Binary(java.lang.String)

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
(package private) static interface	Base64Utils.Base64Delegate
(package private) static class	Base64Utils.CommonsCodecBase64Delegate
(package private) static class	Base64Utils.JdkBase64Delegate

Field Summary

Fields

Modifier and Type	Field and Description
private static java.nio.charset.Charset	DEFAULT_CHARSET
private static Base64Utils.Base64Delegate	delegate

Constructor Summary

Constructors

Constructor and Description
Base64Utils()

Method Summary

Modifier and Type	Method and Description
private static void	assertDelegateAvailable() Assert that Byte64 encoding between byte arrays is actually supported.
static byte[]	decode(byte[] src) Base64-decode the given byte array.
static byte[]	decodeFromString(java.lang.String src) Base64-decode the given byte array from an UTF-8 String.
static byte[]	decodeFromUrlSafeString(java.lang.String src) Base64-decode the given byte array from an UTF-8 String using the RFC 4648 "URL and Filename Safe Alphabet".
static byte[]	decodeUrlSafe(byte[] src) Base64-decode the given byte array using the RFC 4648 "URL and Filename Safe Alphabet".
static byte[]	encode(byte[] src) Base64-encode the given byte array.
static java.lang.String	encodeToString(byte[] src) Base64-encode the given byte array to a String.
static java.lang.String	encodeToUrlSafeString(byte[] src) Base64-encode the given byte array to a String using the RFC 4648 "URL and Filename Safe Alphabet".
static byte[]	encodeUrlSafe(byte[] src) Base64-encode the given byte array using the RFC 4648 "URL and Filename Safe Alphabet".

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

DEFAULT_CHARSET

private static final java.nio.charset.Charset DEFAULT_CHARSET

delegate

private static final Base64Utils.Base64Delegate delegate

Constructor Detail

Base64Utils

public Base64Utils()

Method Detail

assertDelegateAvailable

private static void assertDelegateAvailable()

Assert that Byte64 encoding between byte arrays is actually supported.

Throws:

java.lang.IllegalStateException - if neither Java 8 nor Apache Commons Codec is present

encode

public static byte[] encode(byte[] src)

Base64-encode the given byte array.

Parameters:

src - the original byte array (may be null)

Returns:

the encoded byte array (or null if the input was null)

Throws:

java.lang.IllegalStateException - if Base64 encoding between byte arrays is not supported, i.e. neither Java 8 nor Apache Commons Codec is present at runtime

decode

public static byte[] decode(byte[] src)

Base64-decode the given byte array.

Parameters:

src - the encoded byte array (may be null)

Returns:

the original byte array (or null if the input was null)

Throws:

java.lang.IllegalStateException - if Base64 encoding between byte arrays is not supported, i.e. neither Java 8 nor Apache Commons Codec is present at runtime

encodeUrlSafe

public static byte[] encodeUrlSafe(byte[] src)

Base64-encode the given byte array using the RFC 4648 "URL and Filename Safe Alphabet".

Parameters:

src - the original byte array (may be null)

Returns:

the encoded byte array (or null if the input was null)

Throws:

java.lang.IllegalStateException - if Base64 encoding between byte arrays is not supported, i.e. neither Java 8 nor Apache Commons Codec is present at runtime

Since:

4.2.4

decodeUrlSafe

public static byte[] decodeUrlSafe(byte[] src)

Base64-decode the given byte array using the RFC 4648 "URL and Filename Safe Alphabet".

Parameters:

src - the encoded byte array (may be null)

Returns:

the original byte array (or null if the input was null)

Throws:

java.lang.IllegalStateException - if Base64 encoding between byte arrays is not supported, i.e. neither Java 8 nor Apache Commons Codec is present at runtime

Since:

4.2.4

encodeToString

public static java.lang.String encodeToString(byte[] src)

Base64-encode the given byte array to a String.

Parameters:

src - the original byte array (may be null)

Returns:

the encoded byte array as a UTF-8 String (or null if the input was null)

decodeFromString

public static byte[] decodeFromString(java.lang.String src)

Base64-decode the given byte array from an UTF-8 String.

Parameters:

src - the encoded UTF-8 String (may be null)

Returns:

the original byte array (or null if the input was null)

encodeToUrlSafeString

public static java.lang.String encodeToUrlSafeString(byte[] src)

Base64-encode the given byte array to a String using the RFC 4648 "URL and Filename Safe Alphabet".

Parameters:

src - the original byte array (may be null)

Returns:

the encoded byte array as a UTF-8 String (or null if the input was null)

Throws:

java.lang.IllegalStateException - if Base64 encoding between byte arrays is not supported, i.e. neither Java 8 nor Apache Commons Codec is present at runtime

decodeFromUrlSafeString

public static byte[] decodeFromUrlSafeString(java.lang.String src)

Base64-decode the given byte array from an UTF-8 String using the RFC 4648 "URL and Filename Safe Alphabet".

Parameters:

src - the encoded UTF-8 String (may be null)

Returns:

the original byte array (or null if the input was null)

Throws:

java.lang.IllegalStateException - if Base64 encoding between byte arrays is not supported, i.e. neither Java 8 nor Apache Commons Codec is present at runtime