HeaderValueParser

Parses a header value into elements. Parse errors are indicated as RuntimeException.

Some HTTP headers (such as the set-cookie header) have values that can be decomposed into multiple elements. In order to be processed by this parser, such headers must be in the following form:

 header  = [ element ] *( "," [ element ] )
 element = name [ "=" [ value ] ] *( ";" [ param ] )
 param   = name [ "=" [ value ] ]
 name    = token
 value   = ( token | quoted-string )
 token         = 1*<any char except "=", ",", ";", <"> and
                       white space>
 quoted-string = <"> *( text | quoted-char ) <">
 text          = any char except <">
 quoted-char   = "\" char
 

Any amount of white space is allowed between any part of the header, element or param and is ignored. A missing value in any element or param will be stored as the empty String; if the "=" is also missing null will be stored instead.

Parses a single header element. A header element consist of a semicolon-separate list of name=value definitions.

Parses a name=value specification, where the = and value are optional.

Parses a list of name-value pairs. These lists are used to specify parameters to a header element. Parse errors are indicated as RuntimeException.

This method comforms to the generic grammar and formatting rules outlined in the Section 2.2 and Section 3.6 of RFC 2616.

The following rules are used throughout this specification to describe basic parsing constructs. The US-ASCII coded character set is defined by ANSI X3.4-1986.

     OCTET          = 
     CHAR           = 
     UPALPHA        = 
     LOALPHA        = 
     ALPHA          = UPALPHA | LOALPHA
     DIGIT          = 
     CTL            = 
     CR             = 
     LF             = 
     SP             = 
     HT             = 
     <">            = 
 

Many HTTP/1.1 header field values consist of words separated by LWS or special characters. These special characters MUST be in a quoted string to be used within a parameter value (as defined in section 3.6).

 token          = 1*
 separators     = "(" | ")" | "<" | ">" | "@"
                | "," | ";" | ":" | "\" | <">
                | "/" | "[" | "]" | "?" | "="
                | "{" | "}" | SP | HT
 

A string of text is parsed as a single word if it is quoted using double-quote marks.

 quoted-string  = ( <"> *(qdtext | quoted-pair ) <"> )
 qdtext         = >
 

The backslash character ("\") MAY be used as a single-character quoting mechanism only within quoted-string and comment constructs.

 quoted-pair    = "\" CHAR
 

Parameters are in the form of attribute/value pairs.

 parameter               = attribute "=" value
 attribute               = token
 value                   = token | quoted-string