java.lang.Object
- io.helidon.common.http.Http.Header

Enclosing class:

Http
```
public static final class Http.Header
extends Object
```
Utility class with a list of names of standard HTTP headers and related tooling methods.

Field Summary

Fields
Modifier and Type	Field	Description
`static String`	`ACCEPT`	The `"Accept"` header name.
`static String`	`ACCEPT_CHARSET`	The `"Accept-Charset"` header name.
`static String`	`ACCEPT_DATETIME`	The `"Accept-Datetime"` header name.
`static String`	`ACCEPT_ENCODING`	The `"Accept-Encoding"` header name.
`static String`	`ACCEPT_LANGUAGE`	The `"Accept-Language"` header name.
`static String`	`ACCEPT_PATCH`	The `"Accept-Patch"` header name.
`static String`	`ACCEPT_RANGES`	The `"Accept-Ranges"` header name.
`static String`	`AGE`	The `"Age"` header name.
`static String`	`ALLOW`	The `"Allow"` header name.
`static String`	`ALT_SVC`	The `"Alt-Svc"` header name.
`static String`	`AUTHORIZATION`	The `"Authorization"` header name.
`static String`	`CACHE_CONTROL`	The `"Cache-Control"` header name.
`static String`	`CONNECTION`	The `"Connection"` header name.
`static String`	`CONTENT_DISPOSITION`	The `"Content-Disposition"` header name.
`static String`	`CONTENT_ENCODING`	The `"Content-Encoding"` header name.
`static String`	`CONTENT_LANGUAGE`	The `"Content-Language"` header name.
`static String`	`CONTENT_LENGTH`	The `"Content-Length"` header name.
`static String`	`CONTENT_LOCATION`	The `"aa"` header name.
`static String`	`CONTENT_RANGE`	The `"Content-Range"` header name.
`static String`	`CONTENT_TYPE`	The `"Content-Type"` header name.
`static String`	`COOKIE`	The `"Cookie"` header name.
`static String`	`DATE`	The `"Date"` header name.
`static String`	`ETAG`	The `"ETag"` header name.
`static String`	`EXPECT`	The `"Expect"` header name.
`static String`	`EXPIRES`	The `"Expires"` header name.
`static String`	`FORWARDED`	The `"Forwarded"` header name.
`static String`	`FROM`	The `"From"` header name.
`static String`	`HOST`	The `"Host"` header name.
`static String`	`IF_MATCH`	The `"If-Match"` header name.
`static String`	`IF_MODIFIED_SINCE`	The `"If-Modified-Since"` header name.
`static String`	`IF_NONE_MATCH`	The `"If-None-Match"` header name.
`static String`	`IF_RANGE`	The `"If-Range"` header name.
`static String`	`IF_UNMODIFIED_SINCE`	The `"If-Unmodified-Since"` header name.
`static String`	`LAST_MODIFIED`	The `"Last-Modified"` header name.
`static String`	`LINK`	The `"Link"` header name.
`static String`	`LOCATION`	The `"Location"` header name.
`static String`	`MAX_FORWARDS`	The `"Max-Forwards"` header name.
`static String`	`ORIGIN`	The `"Origin"` header name.
`static String`	`PRAGMA`	The `"Pragma"` header name.
`static String`	`PUBLIC_KEY_PINS`	The `"Public-Key-Pins"` header name.
`static String`	`RANGE`	The `"Range"` header name.
`static String`	`REFERER`	The `"Referer"` header name.
`static String`	`RETRY_AFTER`	The `"Retry-After"` header name.
`static String`	`SERVER`	The `"Server"` header name.
`static String`	`SET_COOKIE`	The `"Set-Cookie"` header name.
`static String`	`STRICT_TRANSPORT_SECURITY`	The `"Strict-Transport-Security"` header name.
`static String`	`TE`	The `"TE"` header name.
`static String`	`TRAILER`	The `"Trailer"` header name.
`static String`	`TRANSFER_ENCODING`	The `"Transfer-Encoding"` header name.
`static String`	`TSV`	The `"TSV"` header name.
`static String`	`UPGRADE`	The `"Upgrade"` header name.
`static String`	`USER_AGENT`	The `"User-Agent"` header name.
`static String`	`VARY`	The `"Vary"` header name.
`static String`	`VIA`	The `"Via"` header name.
`static String`	`WARNING`	The `"Warning"` header name.
`static String`	`WWW_AUTHENTICATE`	The `"WWW-Authenticate"` header name.
`static String`	`X_FORWARDED_FOR`	The `X-Forwarded-For` header name.
`static String`	`X_FORWARDED_HOST`	The `X-Forwarded-Host` header name.
`static String`	`X_FORWARDED_PORT`	The `X-Forwarded-Port` header name.
`static String`	`X_FORWARDED_PREFIX`	The `X-Forwarded-Prefix` header name.
`static String`	`X_FORWARDED_PROTO`	The `X-Forwarded-Proto` header name.
`static String`	`X_HELIDON_CN`	The `"X-HELIDON-CN"` header name.

Method Summary
- Methods inherited from class java.lang.Object
  clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - ACCEPT
```
public static final String ACCEPT
```
    The "Accept" header name. Content-Types that are acceptedTypes for the response.
    
    See Also:
    
    Constant Field Values
  - ACCEPT_CHARSET
```
public static final String ACCEPT_CHARSET
```
    The "Accept-Charset" header name. Character sets that are acceptedTypes.
    
    See Also:
    
    Constant Field Values
  - ACCEPT_ENCODING
```
public static final String ACCEPT_ENCODING
```
    The "Accept-Encoding" header name. List of acceptedTypes encodings.
    
    See Also:
    
    Constant Field Values
  - ACCEPT_LANGUAGE
```
public static final String ACCEPT_LANGUAGE
```
    The "Accept-Language" header name. List of acceptedTypes human languages for response.
    
    See Also:
    
    Constant Field Values
  - ACCEPT_DATETIME
```
public static final String ACCEPT_DATETIME
```
    The "Accept-Datetime" header name. Acceptable version in time.
    
    See Also:
    
    Constant Field Values
  - AUTHORIZATION
```
public static final String AUTHORIZATION
```
    The "Authorization" header name. Authentication credentials for HTTP authentication.
    
    See Also:
    
    Constant Field Values
  - COOKIE
```
public static final String COOKIE
```
    The "Cookie" header name. An HTTP cookie previously sent by the server with "Set-Cookie".
    
    See Also:
    
    Constant Field Values
  - EXPECT
```
public static final String EXPECT
```
    The "Expect" header name. Indicates that particular server behaviors are required by the client.
    
    See Also:
    
    Constant Field Values
  - FORWARDED
```
public static final String FORWARDED
```
    The "Forwarded" header name. Disclose original information of a client connecting to a web server through an HTTP proxy.
    
    See Also:
    
    Constant Field Values
  - X_FORWARDED_FOR
```
public static final String X_FORWARDED_FOR
```
    The X-Forwarded-For header name. Used to represent the original host requested by a client, when request passed through a proxy server.
    
    See Also:
    
    Constant Field Values
  - X_FORWARDED_HOST
```
public static final String X_FORWARDED_HOST
```
    The X-Forwarded-Host header name. Used to represent the original host requested by a client, when request passed through a proxy server.
    
    See Also:
    
    Constant Field Values
  - X_FORWARDED_PORT
```
public static final String X_FORWARDED_PORT
```
    The X-Forwarded-Port header name. Used to represent the original port requested by a client, when request passed through a proxy server.
    
    See Also:
    
    Constant Field Values
  - X_FORWARDED_PREFIX
```
public static final String X_FORWARDED_PREFIX
```
    The X-Forwarded-Prefix header name. Used to represent the original path prefix requested by a client, when request passed through a proxy server.
    
    See Also:
    
    Constant Field Values
  - X_FORWARDED_PROTO
```
public static final String X_FORWARDED_PROTO
```
    The X-Forwarded-Proto header name. Used to represent the original protocol used by a client, when request passed through a proxy server.
    
    See Also:
    
    Constant Field Values
  - FROM
```
public static final String FROM
```
    The "From" header name. The email address of the user making the request.
    
    See Also:
    
    Constant Field Values
  - HOST
```
public static final String HOST
```
    The "Host" header name. The domain name of the server (for virtual hosting), and the TCP port number on which the server is listening. The port number may be omitted if the port is the standard port for the service requested.
    
    See Also:
    
    Constant Field Values
  - IF_MATCH
```
public static final String IF_MATCH
```
    The "If-Match" header name. Only perform the action if the client supplied entity matches the same entity on the server. This is mainly for methods like PUT to only update a resource if it has not been modified since the user last updated it.
    
    See Also:
    
    Constant Field Values
  - IF_MODIFIED_SINCE
```
public static final String IF_MODIFIED_SINCE
```
    The "If-Modified-Since" header name. Allows a 304 Not Modified to be returned if content is unchanged.
    
    See Also:
    
    Constant Field Values
  - IF_NONE_MATCH
```
public static final String IF_NONE_MATCH
```
    The "If-None-Match" header name. Allows a 304 Not Modified to be returned if content is unchanged, based on ETAG.
    
    See Also:
    
    Constant Field Values
  - IF_RANGE
```
public static final String IF_RANGE
```
    The "If-Range" header name. If the entity is unchanged, send me the part(s) that I am missing; otherwise, send me the entire new entity.
    
    See Also:
    
    Constant Field Values
  - IF_UNMODIFIED_SINCE
```
public static final String IF_UNMODIFIED_SINCE
```
    The "If-Unmodified-Since" header name. Only send the response if the entity has not been modified since a specific time.
    
    See Also:
    
    Constant Field Values
  - MAX_FORWARDS
```
public static final String MAX_FORWARDS
```
    The "Max-Forwards" header name. Limit the number of times the message can be forwarded through proxies or gateways.
    
    See Also:
    
    Constant Field Values
  - ORIGIN
```
public static final String ORIGIN
```
    The "Origin" header name. Initiates a request for cross-origin resource sharing (asks server for an 'Access-Control-Allow-Origin' response field).
    
    See Also:
    
    Constant Field Values
  - RANGE
```
public static final String RANGE
```
    The "Range" header name. Request only part of an entity. Bytes are numbered from 0.
    
    See Also:
    
    Constant Field Values
  - REFERER
```
public static final String REFERER
```
    The "Referer" header name. This is the address of the previous web page from which a link to the currently requested page was followed. (The word referrer has been misspelled in the RFC as well as in most implementations to the point that it has become standard usage and is considered correct terminology.)
    
    See Also:
    
    Constant Field Values
  - TE
```
public static final String TE
```
    The "TE" header name. The transfer encodings the user agent is willing to acceptedTypes: the same values as for the response header field Transfer-Encoding can be used, plus the trailers value (related to the chunked transfer method) to notify the server it expects to receive additional fields in the trailer after the last, zero-sized, chunk.
    
    See Also:
    
    Constant Field Values
  - USER_AGENT
```
public static final String USER_AGENT
```
    The "User-Agent" header name. The user agent string of the user agent.
    
    See Also:
    
    Constant Field Values
  - VIA
```
public static final String VIA
```
    The "Via" header name. Informs the server of proxies through which the request was sent.
    
    See Also:
    
    Constant Field Values
  - ACCEPT_PATCH
```
public static final String ACCEPT_PATCH
```
    The "Accept-Patch" header name. Specifies which patch document formats this server supports.
    
    See Also:
    
    Constant Field Values
  - ACCEPT_RANGES
```
public static final String ACCEPT_RANGES
```
    The "Accept-Ranges" header name. What partial content range types this server supports via byte serving.
    
    See Also:
    
    Constant Field Values
  - AGE
```
public static final String AGE
```
    The "Age" header name. The age the object has been in a proxy cache in seconds.
    
    See Also:
    
    Constant Field Values
  - ALLOW
```
public static final String ALLOW
```
    The "Allow" header name. Valid actions for a specified resource. To be used for a 405 Method not allowed.
    
    See Also:
    
    Constant Field Values
  - ALT_SVC
```
public static final String ALT_SVC
```
    The "Alt-Svc" header name. A server uses Alt-Svc header (meaning Alternative Services) to indicate that its resources can also be accessed at a different network location (host or port) or using a different protocol.
    
    See Also:
    
    Constant Field Values
  - CACHE_CONTROL
```
public static final String CACHE_CONTROL
```
    The "Cache-Control" header name. Tells all caching mechanisms from server to client whether they may cache this object. It is measured in seconds.
    
    See Also:
    
    Constant Field Values
  - CONNECTION
```
public static final String CONNECTION
```
    The "Connection" header name. Control options for the current connection and list of hop-by-hop response fields.
    
    See Also:
    
    Constant Field Values
  - CONTENT_DISPOSITION
```
public static final String CONTENT_DISPOSITION
```
    The "Content-Disposition" header name. An opportunity to raise a File Download dialogue box for a known MIME type with binary format or suggest a filename for dynamic content. Quotes are necessary with special characters.
    
    See Also:
    
    Constant Field Values
  - CONTENT_ENCODING
```
public static final String CONTENT_ENCODING
```
    The "Content-Encoding" header name. The type of encoding used on the data.
    
    See Also:
    
    Constant Field Values
  - CONTENT_LANGUAGE
```
public static final String CONTENT_LANGUAGE
```
    The "Content-Language" header name. The natural language or languages of the intended audience for the enclosed content.
    
    See Also:
    
    Constant Field Values
  - CONTENT_LENGTH
```
public static final String CONTENT_LENGTH
```
    The "Content-Length" header name. The length of the response body in octets.
    
    See Also:
    
    Constant Field Values
  - CONTENT_LOCATION
```
public static final String CONTENT_LOCATION
```
    The "aa" header name. An alternate location for the returned data.
    
    See Also:
    
    Constant Field Values
  - CONTENT_RANGE
```
public static final String CONTENT_RANGE
```
    The "Content-Range" header name. Where in a full body message this partial message belongs.
    
    See Also:
    
    Constant Field Values
  - CONTENT_TYPE
```
public static final String CONTENT_TYPE
```
    The "Content-Type" header name. The MIME type of this content.
    
    See Also:
    
    Constant Field Values
  - DATE
```
public static final String DATE
```
    The "Date" header name. The date and time that the message was sent (in HTTP-date format as defined by RFC 7231).
    
    See Also:
    
    Constant Field Values
  - ETAG
```
public static final String ETAG
```
    The "ETag" header name. An identifier for a specific version of a resource, often a message digest.
    
    See Also:
    
    Constant Field Values
  - EXPIRES
```
public static final String EXPIRES
```
    The "Expires" header name. Gives the date/time after which the response is considered stale (in HTTP-date format as defined by RFC 7231)
    
    See Also:
    
    Constant Field Values
  - LAST_MODIFIED
```
public static final String LAST_MODIFIED
```
    The "Last-Modified" header name. The last modified date for the requested object (in HTTP-date format as defined by RFC 7231)
    
    See Also:
    
    Constant Field Values
  - LINK
```
public static final String LINK
```
    The "Link" header name. Used to express a typed relationship with another resource, where the relation type is defined by RFC 5988.
    
    See Also:
    
    Constant Field Values
  - LOCATION
```
public static final String LOCATION
```
    The "Location" header name. Used in redirection, or whenRequest a new resource has been created.
    
    See Also:
    
    Constant Field Values
  - PRAGMA
```
public static final String PRAGMA
```
    The "Pragma" header name. Implementation-specific fields that may have various effects anywhere along the request-response chain.
    
    See Also:
    
    Constant Field Values
  - PUBLIC_KEY_PINS
```
public static final String PUBLIC_KEY_PINS
```
    The "Public-Key-Pins" header name. HTTP Public Key Pinning, announces hash of website's authentic TLS certificate.
    
    See Also:
    
    Constant Field Values
  - RETRY_AFTER
```
public static final String RETRY_AFTER
```
    The "Retry-After" header name. If an entity is temporarily unavailable, this instructs the client to try again later. Value could be a specified period of time (in seconds) or an HTTP-date.
    
    See Also:
    
    Constant Field Values
  - SERVER
```
public static final String SERVER
```
    The "Server" header name. A name for the server.
    
    See Also:
    
    Constant Field Values
  - SET_COOKIE
```
public static final String SET_COOKIE
```
    The "Set-Cookie" header name. An HTTP cookie set directive.
    
    See Also:
    
    Constant Field Values
  - STRICT_TRANSPORT_SECURITY
```
public static final String STRICT_TRANSPORT_SECURITY
```
    The "Strict-Transport-Security" header name. A HSTS Policy informing the HTTP client how long to cache the HTTPS only policy and whether this applies to subdomains.
    
    See Also:
    
    Constant Field Values
  - TRAILER
```
public static final String TRAILER
```
    The "Trailer" header name. The Trailer general field value indicates that the given set of header fields is present in the trailer of a message encoded with chunked transfer coding.
    
    See Also:
    
    Constant Field Values
  - TRANSFER_ENCODING
```
public static final String TRANSFER_ENCODING
```
    The "Transfer-Encoding" header name. The form of encoding used to safely transfer the entity to the user. Currently defined methods are: chunked, compress, deflate, gzip, identity.
    
    See Also:
    
    Constant Field Values
  - TSV
```
public static final String TSV
```
    The "TSV" header name. Tracking Status Value, value suggested to be sent in response to a DNT(do-not-track).
    
    See Also:
    
    Constant Field Values
  - UPGRADE
```
public static final String UPGRADE
```
    The "Upgrade" header name. Ask to upgrade to another protocol.
    
    See Also:
    
    Constant Field Values
  - VARY
```
public static final String VARY
```
    The "Vary" header name. Tells downstream proxies how to match future request headers to decide whether the cached response can be used rather than requesting a fresh one from the origin server.
    
    See Also:
    
    Constant Field Values
  - WARNING
```
public static final String WARNING
```
    The "Warning" header name. A general warning about possible problems with the entity body.
    
    See Also:
    
    Constant Field Values
  - WWW_AUTHENTICATE
```
public static final String WWW_AUTHENTICATE
```
    The "WWW-Authenticate" header name. Indicates the authentication scheme that should be used to access the requested entity.
    
    See Also:
    
    Constant Field Values
  - X_HELIDON_CN
```
public static final String X_HELIDON_CN
```
    The "X-HELIDON-CN" header name. Corresponds to the certificate CN subject value when client authentication enabled. This header will be removed if it is part of the request.
    
    See Also:
    
    Constant Field Values

Class Http.Header

Field Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

ACCEPT

ACCEPT_CHARSET

ACCEPT_ENCODING

ACCEPT_LANGUAGE

ACCEPT_DATETIME

AUTHORIZATION

COOKIE

EXPECT

FORWARDED

X_FORWARDED_FOR

X_FORWARDED_HOST

X_FORWARDED_PORT

X_FORWARDED_PREFIX

X_FORWARDED_PROTO

FROM

HOST

IF_MATCH

IF_MODIFIED_SINCE

IF_NONE_MATCH

IF_RANGE

IF_UNMODIFIED_SINCE

MAX_FORWARDS

ORIGIN

RANGE

REFERER

TE

USER_AGENT

VIA

ACCEPT_PATCH

ACCEPT_RANGES

AGE

ALLOW

ALT_SVC

CACHE_CONTROL

CONNECTION

CONTENT_DISPOSITION

CONTENT_ENCODING

CONTENT_LANGUAGE

CONTENT_LENGTH

CONTENT_LOCATION

CONTENT_RANGE

CONTENT_TYPE

DATE

ETAG

EXPIRES

LAST_MODIFIED

LINK

LOCATION

PRAGMA

PUBLIC_KEY_PINS

RETRY_AFTER

SERVER

SET_COOKIE

STRICT_TRANSPORT_SECURITY

TRAILER

TRANSFER_ENCODING

TSV

UPGRADE

VARY

WARNING

WWW_AUTHENTICATE

X_HELIDON_CN