Package javax.mail.internet

Class HeaderTokenizer

java.lang.Object

javax.mail.internet.HeaderTokenizer

public class HeaderTokenizer
extends Object

This class tokenizes RFC822 and MIME headers into the basic symbols specified by RFC822 and MIME.

This class handles folded headers (ie headers with embedded CRLF SPACE sequences). The folds are removed in the returned tokens.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	HeaderTokenizer.Token	The Token class represents tokens returned by the HeaderTokenizer.

Field Summary

Fields

Modifier and Type	Field	Description
static final String	MIME	MIME specials
static final String	RFC822	RFC822 specials

Constructor Summary

Constructors

Constructor	Description
HeaderTokenizer(String header)	Constructor.
HeaderTokenizer(String header, String delimiters)	Constructor.
HeaderTokenizer(String header, String delimiters, boolean skipComments)	Constructor that takes a rfc822 style header.

Method Summary

Modifier and Type	Method	Description
String	getRemainder()	Return the rest of the Header.
HeaderTokenizer.Token	next()	Parses the next token from this String.
HeaderTokenizer.Token	next(char endOfAtom)	Parses the next token from this String.
HeaderTokenizer.Token	next(char endOfAtom, boolean keepEscapes)	Parses the next token from this String.
HeaderTokenizer.Token	peek()	Peek at the next token, without actually removing the token from the parse stream.

Methods inherited from class java.lang.Object

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

Field Details

RFC822

public static final String RFC822

RFC822 specials

See Also:

• Constant Field Values

MIME

public static final String MIME

MIME specials

See Also:

• Constant Field Values

Constructor Details

HeaderTokenizer

public HeaderTokenizer(String header,
 String delimiters,
 boolean skipComments)

Constructor that takes a rfc822 style header.

Parameters:

header - The rfc822 header to be tokenized

delimiters - Set of delimiter characters to be used to delimit ATOMS. These are usually RFC822 or MIME

skipComments - If true, comments are skipped and not returned as tokens

HeaderTokenizer

public HeaderTokenizer(String header,
 String delimiters)

Constructor. Comments are ignored and not returned as tokens

Parameters:

header - The header that is tokenized

delimiters - The delimiters to be used

HeaderTokenizer

public HeaderTokenizer(String header)

Constructor. The RFC822 defined delimiters - RFC822 - are used to delimit ATOMS. Also comments are skipped and not returned as tokens

Method Details

next

public HeaderTokenizer.Token next()
                           throws ParseException

Parses the next token from this String.

Clients sit in a loop calling next() to parse successive tokens until an EOF Token is returned.

Returns:

the next Token

Throws:

ParseException - if the parse fails

next

public HeaderTokenizer.Token next(char endOfAtom)
                           throws ParseException

Parses the next token from this String. If endOfAtom is not NUL, the token extends until the endOfAtom character is seen, or to the end of the header. This method is useful when parsing headers that don't obey the MIME specification, e.g., by failing to quote parameter values that contain spaces.

Parameters:

endOfAtom - if not NUL, character marking end of token

Returns:

the next Token

Throws:

ParseException - if the parse fails

Since:

JavaMail 1.5

next

public HeaderTokenizer.Token next(char endOfAtom,
 boolean keepEscapes)
                           throws ParseException

Parses the next token from this String. endOfAtom is handled as above. If keepEscapes is true, any backslash escapes are preserved in the returned string. This method is useful when parsing headers that don't obey the MIME specification, e.g., by failing to escape backslashes in the filename parameter.

Parameters:

endOfAtom - if not NUL, character marking end of token

keepEscapes - keep all backslashes in returned string?

Returns:

the next Token

Throws:

ParseException - if the parse fails

Since:

JavaMail 1.5

peek

public HeaderTokenizer.Token peek()
                           throws ParseException

Peek at the next token, without actually removing the token from the parse stream. Invoking this method multiple times will return successive tokens, until next() is called.

Returns:

the next Token

Throws:

ParseException - if the parse fails

getRemainder

public String getRemainder()

Return the rest of the Header.

Returns:

String rest of header. null is returned if we are already at end of header