com.github.davidcarboni.cryptolite

Class ByteArray

java.lang.Object

com.github.davidcarboni.cryptolite.ByteArray

public class ByteArray
extends Object

This class provides the ability to convert Strings, Base-64 and hexadecimal to a byte array and vice versa. Cryptography is mainly about manipulating byte arrays, so this class provides the translations you need:

• Plain-text strings need to be converted to a byte array for encryption and, after decryption, need to be converted from a byte array back to a String. This is done using "UTF8" encoding.
• Encrypted byte arrays look like random bytes, which means they can't be reliably represented as a String. The best way to represent arbitrary bytes as a String is using Base-64. This class lets you convert a byte array of encrypted data to Base-64 so it can be easily stored and back again so it can be decrypted
• Finally, this class also allows you to transform a byte array to a hexadecimal String and back again. This is most useful in development when you need to print out values to see what's going on. Conversion from hexadecimal to byte array is occasionally useful, but chances are you'll use byte[] to hex most of the time.

Author:

David Carboni

Field Summary

Fields

Modifier and Type	Field and Description
static String	ENCODING The encoding to use for string operations.

Constructor Summary

Constructors

Constructor and Description
ByteArray()

Method Summary

Methods

Modifier and Type	Method and Description
static byte[]	fromBase64String(String base64) Decodes the given base-64 string into a byte array.
static byte[]	fromHexString(String hex) With thanks to StackOverflow: Convert a string representation of a hex dump to a byte array using Java?
static byte[]	fromString(String string) Converts the given String to a byte array using "UTF8".
static String	toBase64String(byte[] bytes) Encodes the given byte array as a base-64 String.
static String	toHexString(byte[] bytes) Renders the given byte array as a hex String.
static String	toString(byte[] bytes) Converts the given byte array to a String using "UTF8".

Methods inherited from class java.lang.Object

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

Field Detail

ENCODING

public static final String ENCODING

The encoding to use for string operations.

See Also:

Constant Field Values

Constructor Detail

ByteArray

public ByteArray()

Method Detail

toHexString

public static String toHexString(byte[] bytes)

Renders the given byte array as a hex String. This is a convenience method useful for checking values during development. Internally, this checks for null and then calls the Apache commons-codec method Hex.encodeHexString(byte[]).

Parameters:

bytes - The array to be rendered.

Returns:

A string representation of the byte array.

fromHexString

public static byte[] fromHexString(String hex)

With thanks to StackOverflow: Convert a string representation of a hex dump to a byte array using Java?

Parameters:

hex - The hex String to parse. If it starts with 0x, this will be ignored automatically.

Returns:

A byte array, as parsed from the given String

toBase64String

public static String toBase64String(byte[] bytes)

Encodes the given byte array as a base-64 String. Internally, this checks for null and then calls the Apache commons-codec method Base64.encodeBase64String(byte[]).

Parameters:

bytes - The array to be encoded.

Returns:

The byte array encoded using base-64.

fromBase64String

public static byte[] fromBase64String(String base64)

Decodes the given base-64 string into a byte array.

Parameters:

base64 - A base-64 encoded string.

Returns:

The decoded byte array.

fromString

public static byte[] fromString(String string)

Converts the given String to a byte array using "UTF8".

Parameters:

string - The String to be converted to a byte array.

Returns:

A byte array representing the String.

toString

public static String toString(byte[] bytes)

Converts the given byte array to a String using "UTF8".

Parameters:

bytes - The byte array to be converted to a String.

Returns:

The String represented by the given bytes.