us.monoid.util
Class EncoderUtil

java.lang.Object
  us.monoid.util.EncoderUtil

public class EncoderUtil
extends Object

Static methods for encoding header field values. This includes encoded-words as defined in RFC 2047 or display-names of an e-mail address, for example.

Nested Class Summary

static class	EncoderUtil.Encoding Selects one of the two encodings specified in RFC 2047.
static class	EncoderUtil.Usage Indicates the intended usage of an encoded word.

Field Summary

static Charset

US_ASCII

Method Summary

static String	encodeAddressDisplayName(String displayName) Encodes the display-name portion of an address.
static String	encodeAddressLocalPart(String localPart) Encodes the local part of an address specification as described in RFC 5322 section 3.4.1.
static String	encodeB(byte[] bytes) Encodes the specified byte array using the B encoding defined in RFC 2047.
static String	encodeEncodedWord(String text, EncoderUtil.Usage usage) Encodes the specified text into an encoded word or a sequence of encoded words separated by space.
static String	encodeEncodedWord(String text, EncoderUtil.Usage usage, int usedCharacters) Encodes the specified text into an encoded word or a sequence of encoded words separated by space.
static String	encodeEncodedWord(String text, EncoderUtil.Usage usage, int usedCharacters, Charset charset, EncoderUtil.Encoding encoding) Encodes the specified text into an encoded word or a sequence of encoded words separated by space.
static String	encodeHeaderParameter(String name, String value) Encodes the specified strings into a header parameter as described in RFC 2045 section 5.1 and RFC 2183 section 2.
static String	encodeIfNecessary(String text, EncoderUtil.Usage usage, int usedCharacters) Shortcut method that encodes the specified text into an encoded-word if the text has to be encoded.
static String	encodeQ(byte[] bytes, EncoderUtil.Usage usage) Encodes the specified byte array using the Q encoding defined in RFC 2047.
static boolean	hasToBeEncoded(String text, int usedCharacters) Determines if the specified string has to encoded into an encoded-word.
static boolean	isToken(String str) Tests whether the specified string is a token as defined in RFC 2045 section 5.1.

Methods inherited from class java.lang.Object

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

Field Detail

US_ASCII

public static final Charset US_ASCII

Method Detail

encodeAddressDisplayName

public static String encodeAddressDisplayName(String displayName)

Encodes the display-name portion of an address. See RFC 5322 section 3.4 and RFC 2047 section 5.3. The specified string should not be folded.

Parameters:

displayName - display-name to encode.

Returns:

encoded display-name.

encodeAddressLocalPart

public static String encodeAddressLocalPart(String localPart)

Encodes the local part of an address specification as described in RFC 5322 section 3.4.1. Leading and trailing CFWS should have been removed before calling this method. The specified string should not contain any illegal (control or non-ASCII) characters.

Parameters:

localPart - the local part to encode

Returns:

the encoded local part.

encodeHeaderParameter

public static String encodeHeaderParameter(String name,
                                           String value)

Encodes the specified strings into a header parameter as described in RFC 2045 section 5.1 and RFC 2183 section 2. The specified strings should not contain any illegal (control or non-ASCII) characters.

Parameters:

name - parameter name.

value - parameter value.

Returns:

encoded result.

encodeIfNecessary

public static String encodeIfNecessary(String text,
                                       EncoderUtil.Usage usage,
                                       int usedCharacters)

Shortcut method that encodes the specified text into an encoded-word if the text has to be encoded.

Parameters:

text - text to encode.

usage - whether the encoded-word is to be used to replace a text token or a word entity (see RFC 822).

usedCharacters - number of characters already used up ( 0 <= usedCharacters <= 50).

Returns:

the specified text if encoding is not necessary or an encoded word or a sequence of encoded words otherwise.

hasToBeEncoded

public static boolean hasToBeEncoded(String text,
                                     int usedCharacters)

Determines if the specified string has to encoded into an encoded-word. Returns true if the text contains characters that don't fall into the printable ASCII character set or if the text contains a 'word' (sequence of non-whitespace characters) longer than 77 characters (including characters already used up in the line).

Parameters:

text - text to analyze.

usedCharacters - number of characters already used up ( 0 <= usedCharacters <= 50).

Returns:

true if the specified text has to be encoded into an encoded-word, false otherwise.

encodeEncodedWord

public static String encodeEncodedWord(String text,
                                       EncoderUtil.Usage usage)

Encodes the specified text into an encoded word or a sequence of encoded words separated by space. The text is separated into a sequence of encoded words if it does not fit in a single one.

The charset to encode the specified text into a byte array and the encoding to use for the encoded-word are detected automatically.

This method assumes that zero characters have already been used up in the current line.

Parameters:

text - text to encode.

usage - whether the encoded-word is to be used to replace a text token or a word entity (see RFC 822).

Returns:

the encoded word (or sequence of encoded words if the given text does not fit in a single encoded word).

See Also:

hasToBeEncoded(String, int)

encodeEncodedWord

public static String encodeEncodedWord(String text,
                                       EncoderUtil.Usage usage,
                                       int usedCharacters)

Encodes the specified text into an encoded word or a sequence of encoded words separated by space. The text is separated into a sequence of encoded words if it does not fit in a single one.

The charset to encode the specified text into a byte array and the encoding to use for the encoded-word are detected automatically.

Parameters:

text - text to encode.

usage - whether the encoded-word is to be used to replace a text token or a word entity (see RFC 822).

usedCharacters - number of characters already used up ( 0 <= usedCharacters <= 50).

Returns:

the encoded word (or sequence of encoded words if the given text does not fit in a single encoded word).

See Also:

hasToBeEncoded(String, int)

encodeEncodedWord

public static String encodeEncodedWord(String text,
                                       EncoderUtil.Usage usage,
                                       int usedCharacters,
                                       Charset charset,
                                       EncoderUtil.Encoding encoding)

Encodes the specified text into an encoded word or a sequence of encoded words separated by space. The text is separated into a sequence of encoded words if it does not fit in a single one.

Parameters:

text - text to encode.

usage - whether the encoded-word is to be used to replace a text token or a word entity (see RFC 822).

usedCharacters - number of characters already used up ( 0 <= usedCharacters <= 50).

charset - the Java charset that should be used to encode the specified string into a byte array. A suitable charset is detected automatically if this parameter is null.

encoding - the encoding to use for the encoded-word (either B or Q). A suitable encoding is automatically chosen if this parameter is null.

Returns:

the encoded word (or sequence of encoded words if the given text does not fit in a single encoded word).

See Also:

hasToBeEncoded(String, int)

encodeB

public static String encodeB(byte[] bytes)

Encodes the specified byte array using the B encoding defined in RFC 2047.

Parameters:

bytes - byte array to encode.

Returns:

encoded string.

encodeQ

public static String encodeQ(byte[] bytes,
                             EncoderUtil.Usage usage)

Encodes the specified byte array using the Q encoding defined in RFC 2047.

Parameters:

bytes - byte array to encode.

usage - whether the encoded-word is to be used to replace a text token or a word entity (see RFC 822).

Returns:

encoded string.

isToken

public static boolean isToken(String str)

Tests whether the specified string is a token as defined in RFC 2045 section 5.1.

Parameters:

str - string to test.

Returns:

true if the specified string is a RFC 2045 token, false otherwise.