org.apache.commons.httpclient
Class HeaderElement

java.lang.Object
  |
  +--org.apache.commons.httpclient.NameValuePair
        |
        +--org.apache.commons.httpclient.HeaderElement

All Implemented Interfaces:

Serializable

public class HeaderElement

extends NameValuePair

One element of an HTTP header's value.

Some HTTP headers (such as the set-cookie header) have values that can be decomposed into multiple elements. 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.

This class represents an individual header element, containing both a name/value pair (value may be null) and optionally a set of additional parameters.

This class also exposes a parse(java.lang.String) method for parsing a Header value into an array of elements.

Since:

1.0

Version:

$Revision: 1.18.2.1 $ $Date: 2004/02/22 18:21:13 $

Author:

B.C. Holmes, Park, Sung-Gu, Mike Bowler

See Also:

Header, Serialized Form

Constructor Summary

HeaderElement()
Default constructor.

HeaderElement(String name, String value)
Constructor.

HeaderElement(String name, String value, NameValuePair[] parameters)
Constructor with name, value and parameters.

Method Summary

(package private) static void	() Static initializer for #SEPARATORS, #TOKEN_CHAR, and #UNSAFE_CHAR.
NameValuePair	getParameterByName(String name) Returns parameter with the given name, if found.
NameValuePair[]	getParameters() Get parameters, if any.
static HeaderElement[]	parse(String headerValue) This parses the value part of a header.
protected void	setParameters(NameValuePair[] pairs)

Methods inherited from class org.apache.commons.httpclient.NameValuePair

equals, getName, getValue, hashCode, setName, setValue, toString

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

HeaderElement

public HeaderElement()

Default constructor.

HeaderElement

public HeaderElement(String name,
                     String value)

Constructor.

Parameters:

name - my name

value - my (possibly null) value

HeaderElement

public HeaderElement(String name,
                     String value,
                     NameValuePair[] parameters)

Constructor with name, value and parameters.

Parameters:

name - my name

value - my (possibly null) value

parameters - my (possibly null) parameters

Method Detail

static void ()

Static initializer for #SEPARATORS, #TOKEN_CHAR, and #UNSAFE_CHAR.

getParameters

public NameValuePair[] getParameters()

Get parameters, if any.

Returns:

parameters as an array of NameValuePairs

Since:

2.0

setParameters

protected void setParameters(NameValuePair[] pairs)

Parameters:

pairs - The new parameters. May be null.

parse

public static final HeaderElement[] parse(String headerValue)
                                   throws HttpException

This parses the value part of a header. The result is an array of HeaderElement objects.

Parameters:

headerValue - the string representation of the header value (as received from the web server).

Returns:

the header elements containing Header elements.

Throws:

HttpException - if the above syntax rules are violated.

getParameterByName

public NameValuePair getParameterByName(String name)

Returns parameter with the given name, if found. Otherwise null is returned

Parameters:

name - The name to search by.

Returns:

NameValuePair parameter with the given name