MimeUtility

Decode the given input stream. The Input stream returned is the decoded input stream. All the encodings defined in RFC 2045 are supported here. They include "base64", "quoted-printable", "7bit", "8bit", and "binary". In addition, "uuencode" is also supported.

In the current implementation, if the mail.mime.ignoreunknownencoding system property is set to "true", unknown encoding values are ignored and the original InputStream is returned.

Decode "unstructured" headers, that is, headers that are defined as '*text' as per RFC 822.

The string is decoded using the algorithm specified in RFC 2047, Section 6.1. If the charset-conversion fails for any sequence, an UnsupportedEncodingException is thrown. If the String is not an RFC 2047 style encoded header, it is returned as-is

Example of usage:

  MimePart part = ...
  String rawvalue = null;
  String  value = null;
  try {
    if ((rawvalue = part.getHeader("X-mailer")[0]) != null)
      value = MimeUtility.decodeText(rawvalue);
  } catch (UnsupportedEncodingException e) {
      // Don't care
      value = rawvalue;
  } catch (MessagingException me) { }

  return value;

 

The string is parsed using the rules in RFC 2047 and RFC 2231 for parsing an "encoded-word". If the parse fails, a ParseException is thrown. Otherwise, it is transfer-decoded, and then charset-converted into Unicode. If the charset-conversion fails, an UnsupportedEncodingException is thrown.

Wrap an encoder around the given output stream. All the encodings defined in RFC 2045 are supported here. They include "base64", "quoted-printable", "7bit", "8bit" and "binary". In addition, "uuencode" is also supported. The filename parameter is used with the "uuencode" encoding and is included in the encoded output.

Wrap an encoder around the given output stream. All the encodings defined in RFC 2045 are supported here. They include "base64", "quoted-printable", "7bit", "8bit" and "binary". In addition, "uuencode" is also supported.

Encode a RFC 822 "text" token into mail-safe form as per RFC 2047.

The given Unicode string is examined for non US-ASCII characters. If the string contains only US-ASCII characters, it is returned as-is. If the string contains non US-ASCII characters, it is first character-encoded using the specified charset, then transfer-encoded using either the B or Q encoding. The resulting bytes are then returned as a Unicode string containing only ASCII characters.

Note that this method should be used to encode only "unstructured" RFC 822 headers.

Encode a RFC 822 "text" token into mail-safe form as per RFC 2047.

The given Unicode string is examined for non US-ASCII characters. If the string contains only US-ASCII characters, it is returned as-is. If the string contains non US-ASCII characters, it is first character-encoded using the platform's default charset, then transfer-encoded using either the B or Q encoding. The resulting bytes are then returned as a Unicode string containing only ASCII characters.

Note that this method should be used to encode only "unstructured" RFC 822 headers.

Example of usage:

  MimePart part = ...
  String rawvalue = "FooBar Mailer, Japanese version 1.1"
  try {
    // If we know for sure that rawvalue contains only US-ASCII
    // characters, we can skip the encoding part
    part.setHeader("X-mailer", MimeUtility.encodeText(rawvalue));
  } catch (UnsupportedEncodingException e) {
    // encoding failure
  } catch (MessagingException me) {
   // setHeader() failure
  }

 

Encode a RFC 822 "word" token into mail-safe form as per RFC 2047.

The given Unicode string is examined for non US-ASCII characters. If the string contains only US-ASCII characters, it is returned as-is. If the string contains non US-ASCII characters, it is first character-encoded using the specified charset, then transfer-encoded using either the B or Q encoding. The resulting bytes are then returned as a Unicode string containing only ASCII characters.

Encode a RFC 822 "word" token into mail-safe form as per RFC 2047.

The given Unicode string is examined for non US-ASCII characters. If the string contains only US-ASCII characters, it is returned as-is. If the string contains non US-ASCII characters, it is first character-encoded using the platform's default charset, then transfer-encoded using either the B or Q encoding. The resulting bytes are then returned as a Unicode string containing only ASCII characters.

This method is meant to be used when creating RFC 822 "phrases". The InternetAddress class, for example, uses this to encode it's 'phrase' component.

Fold a string at linear whitespace so that each line is no longer than 76 characters, if possible. If there are more than 76 non-whitespace characters consecutively, the string is folded at the first whitespace after that sequence. The parameter used indicates how many characters have been used in the current line; it is usually the length of the header name.

Note that line breaks in the string aren't escaped; they probably should be.

Get the default charset corresponding to the system's current default locale. If the System property mail.mime.charset is set, a system charset corresponding to this MIME charset will be returned.

Same as getEncoding(DataSource) except that instead of reading the data from an InputStream it uses the writeTo method to examine the data. This is more efficient in the common case of a DataHandler created with an object and a MIME type (for example, a "text/plain" String) because all the I/O is done in this thread. In the case requiring an InputStream the DataHandler uses a thread, a pair of pipe streams, and the writeTo method to produce the data.

Get the content-transfer-encoding that should be applied to the input stream of this datasource, to make it mailsafe.

The algorithm used here is:

• If the primary type of this datasource is "text" and if all the bytes in its input stream are US-ASCII, then the encoding is "7bit". If more than half of the bytes are non-US-ASCII, then the encoding is "base64". If less than half of the bytes are non-US-ASCII, then the encoding is "quoted-printable".
• If the primary type of this datasource is not "text", then if all the bytes of its input stream are US-ASCII, the encoding is "7bit". If there is even one non-US-ASCII character, the encoding is "base64".

Convert a MIME charset name into a valid Java charset name.

Convert a java charset into its MIME charset name.

Note that a future version of JDK (post 1.2) might provide this functionality, in which case, we may deprecate this method then.

A utility method to quote a word, if the word contains any characters from the specified 'specials' list.

The HeaderTokenizer class defines two special sets of delimiters - MIME and RFC 822.

This method is typically used during the generation of RFC 822 and MIME header fields.

Unfold a folded header. Any line breaks that aren't escaped and are followed by whitespace are removed.