Class Cookie
- All Implemented Interfaces:
- Serializable,- Cloneable
A cookie has a name, a single value, and optional attributes such as a comment, path and domain qualifiers, a maximum age, and a version number. Some Web browsers have bugs in how they handle the optional attributes, so use them sparingly to improve the interoperability of your servlets.
 The servlet sends cookies to the browser by using the HttpServletResponse.addCookie(javax.servlet.http.Cookie) method, which adds fields
 to HTTP response headers to send cookies to the browser, one at a time. The browser is expected to support 50 cookies
 for each domain, 3000 cookies total, and may limit cookie size to 4 KiB each.
 
 The browser returns cookies to the servlet by adding fields to HTTP request headers. Cookies can be retrieved from a
 request by using the HttpServletRequest.getCookies() method. Several cookies might have the same name but
 different path attributes.
 
Cookies affect the caching of the Web pages that use them. HTTP 1.0 does not cache pages that use cookies created with this class. This class does not support the cache control defined with HTTP 1.1.
This class supports both the RFC 2109 and the RFC 6265 specifications. By default, cookies are created using RFC 6265.
- See Also:
- 
Constructor SummaryConstructors
- 
Method SummaryModifier and TypeMethodDescriptionclone()Overrides the standardjava.lang.Object.clonemethod to return a copy of this cookie.Returns the comment describing the purpose of this cookie, ornullif the cookie has no comment.Returns the domain name set for this cookie.intReturns the maximum age of the cookie, specified in seconds, By default,-1indicating the cookie will persist until browser shutdown.getName()Returns the name of the cookie.getPath()Returns the path on the server to which the browser returns this cookie.booleanReturnstrueif the browser is sending cookies only over a secure protocol, orfalseif the browser can send cookies using any protocol.getValue()Returns the value of the cookie.intReturns the version of the protocol this cookie complies with.booleanGets the flag that controls if this cookie will be hidden from scripts on the client side.voidsetComment(String purpose) Specifies a comment that describes a cookie's purpose.voidSpecifies the domain within which this cookie should be presented.voidsetHttpOnly(boolean httpOnly) Sets the flag that controls if this cookie will be hidden from scripts on the client side.voidsetMaxAge(int expiry) Sets the maximum age of the cookie in seconds.voidSpecifies a path for the cookie to which the client should return the cookie.voidsetSecure(boolean flag) Indicates to the browser whether the cookie should only be sent using a secure protocol, such as HTTPS or SSL.voidAssigns a new value to a cookie after the cookie is created.voidsetVersion(int v) Sets the version of the cookie protocol this cookie complies with.
- 
Constructor Details- 
CookieConstructs a cookie with a specified name and value.The name must conform to RFC 2109. That means it can contain only ASCII alphanumeric characters and cannot contain commas, semicolons, or white space or begin with a $ character. The cookie's name cannot be changed after creation. The value can be anything the server chooses to send. Its value is probably of interest only to the server. The cookie's value can be changed after creation with the setValuemethod.By default, cookies are created according to the Netscape cookie specification. The version can be changed with the setVersionmethod.- Parameters:
- name- a- Stringspecifying the name of the cookie
- value- a- Stringspecifying the value of the cookie
- Throws:
- IllegalArgumentException- if the cookie name contains illegal characters (for example, a comma, space, or semicolon) or it is one of the tokens reserved for use by the cookie protocol
- See Also:
 
 
- 
- 
Method Details- 
setCommentSpecifies a comment that describes a cookie's purpose. The comment is useful if the browser presents the cookie to the user. Comments are not supported by Netscape Version 0 cookies.- Parameters:
- purpose- a- Stringspecifying the comment to display to the user
- See Also:
 
- 
getCommentReturns the comment describing the purpose of this cookie, ornullif the cookie has no comment.- Returns:
- a Stringcontaining the comment, ornullif none
- See Also:
 
- 
setDomainSpecifies the domain within which this cookie should be presented.The form of the domain name is specified by RFC 2109. A domain name begins with a dot ( .foo.com) and means that the cookie is visible to servers in a specified Domain Name System (DNS) zone (for example,www.foo.com, but nota.b.foo.com). By default, cookies are only returned to the server that sent them.- Parameters:
- pattern- a- Stringcontaining the domain name within which this cookie is visible; form is according to RFC 2109
- See Also:
 
- 
getDomainReturns the domain name set for this cookie. The form of the domain name is set by RFC 2109.- Returns:
- a Stringcontaining the domain name
- See Also:
 
- 
setMaxAgepublic void setMaxAge(int expiry) Sets the maximum age of the cookie in seconds.A positive value indicates that the cookie will expire after that many seconds have passed. Note that the value is the maximum age when the cookie will expire, not the cookie's current age. A negative value means that the cookie is not stored persistently and will be deleted when the Web browser exits. A zero value causes the cookie to be deleted. - Parameters:
- expiry- an integer specifying the maximum age of the cookie in seconds; if negative, means the cookie is not stored; if zero, deletes the cookie
- See Also:
 
- 
getMaxAgepublic int getMaxAge()Returns the maximum age of the cookie, specified in seconds, By default,-1indicating the cookie will persist until browser shutdown.- Returns:
- an integer specifying the maximum age of the cookie in seconds; if negative, means the cookie persists until browser shutdown
- See Also:
 
- 
setPathSpecifies a path for the cookie to which the client should return the cookie.The cookie is visible to all the pages in the directory you specify, and all the pages in that directory's subdirectories. A cookie's path must include the servlet that set the cookie, for example, /catalog, which makes the cookie visible to all directories on the server under /catalog. Consult RFC 2109 (available on the Internet) for more information on setting path names for cookies. - Parameters:
- uri- a- Stringspecifying a path
- See Also:
 
- 
getPathReturns the path on the server to which the browser returns this cookie. The cookie is visible to all subpaths on the server.- Returns:
- a Stringspecifying a path that contains a servlet name, for example, /catalog
- See Also:
 
- 
setSecurepublic void setSecure(boolean flag) Indicates to the browser whether the cookie should only be sent using a secure protocol, such as HTTPS or SSL.The default value is false.- Parameters:
- flag- if- true, sends the cookie from the browser to the server only when using a secure protocol; if- false, sent on any protocol
- See Also:
 
- 
getSecurepublic boolean getSecure()Returnstrueif the browser is sending cookies only over a secure protocol, orfalseif the browser can send cookies using any protocol.- Returns:
- trueif the browser uses a secure protocol; otherwise,- false
- See Also:
 
- 
getNameReturns the name of the cookie. The name cannot be changed after creation.- Returns:
- a Stringspecifying the cookie's name
 
- 
setValueAssigns a new value to a cookie after the cookie is created. If you use a binary value, you may want to use BASE64 encoding.With Version 0 cookies, values should not contain white space, brackets, parentheses, equals signs, commas, double quotes, slashes, question marks, at signs, colons, and semicolons. Empty values may not behave the same way on all browsers. - Parameters:
- newValue- a- Stringspecifying the new value
- See Also:
 
- 
getValueReturns the value of the cookie.- Returns:
- a Stringcontaining the cookie's present value
- See Also:
 
- 
getVersionpublic int getVersion()Returns the version of the protocol this cookie complies with. Version 1 complies with RFC 2109, and version 0 complies with the original cookie specification drafted by Netscape. Cookies provided by a browser use and identify the browser's cookie version.- Returns:
- 0 if the cookie complies with the original Netscape specification; 1 if the cookie complies with RFC 2109
- See Also:
 
- 
setVersionpublic void setVersion(int v) Sets the version of the cookie protocol this cookie complies with. Version 0 complies with the original Netscape cookie specification. Version 1 complies with RFC 2109.Since RFC 2109 is still somewhat new, consider version 1 as experimental; do not use it yet on production sites. - Parameters:
- v- 0 if the cookie should comply with the original Netscape specification; 1 if the cookie should comply with RFC 2109
- See Also:
 
- 
cloneOverrides the standardjava.lang.Object.clonemethod to return a copy of this cookie.
- 
setHttpOnlypublic void setHttpOnly(boolean httpOnly) Sets the flag that controls if this cookie will be hidden from scripts on the client side.- Parameters:
- httpOnly- The new value of the flag
- Since:
- Servlet 3.0
 
- 
isHttpOnlypublic boolean isHttpOnly()Gets the flag that controls if this cookie will be hidden from scripts on the client side.- Returns:
- trueif the cookie is hidden from scripts, else- false
- Since:
- Servlet 3.0
 
 
-