javax.servlet.http.Cookie Maven / Gradle / Ivy
/*
* Copyright (c) 1997-2018 Oracle and/or its affiliates. All rights reserved.
* Copyright 2004 The Apache Software Foundation
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package javax.servlet.http;
import java.io.Serializable;
import java.text.MessageFormat;
import java.util.Locale;
import java.util.ResourceBundle;
/**
*
* Creates a cookie, a small amount of information sent by a servlet to
* a Web browser, saved by the browser, and later sent back to the server.
* A cookie's value can uniquely
* identify a client, so cookies are commonly used for session management.
*
* 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
* {@link HttpServletResponse#addCookie} method, which adds
* fields to HTTP response headers to send cookies to the
* browser, one at a time. The browser is expected to
* support 20 cookies for each Web server, 300 cookies total, and
* may limit cookie size to 4 KB 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 {@link 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 Version 0 (by Netscape) and Version 1
* (by RFC 2109) cookie specifications. By default, cookies are
* created using Version 0 to ensure the best interoperability.
*
* @author Various
*/
public class Cookie implements Cloneable, Serializable {
private static final long serialVersionUID = -6454587001725327448L;
private static final String TSPECIALS;
private static final String LSTRING_FILE =
"javax.servlet.http.LocalStrings";
private static ResourceBundle lStrings =
ResourceBundle.getBundle(LSTRING_FILE);
static {
if (Boolean.valueOf(System.getProperty("org.glassfish.web.rfc2109_cookie_names_enforced", "true"))) {
TSPECIALS = "/()<>@,;:\\\"[]?={} \t";
} else {
TSPECIALS = ",; ";
}
}
//
// The value of the cookie itself.
//
private String name; // NAME= ... "$Name" style is reserved
private String value; // value of NAME
//
// Attributes encoded in the header's cookie fields.
//
private String comment; // ;Comment=VALUE ... describes cookie's use
// ;Discard ... implied by maxAge < 0
private String domain; // ;Domain=VALUE ... domain that sees cookie
private int maxAge = -1; // ;Max-Age=VALUE ... cookies auto-expire
private String path; // ;Path=VALUE ... URLs that see the cookie
private boolean secure; // ;Secure ... e.g. use SSL
private int version = 0; // ;Version=1 ... means RFC 2109++ style
private boolean isHttpOnly = false;
/**
* Constructs a cookie with the specified name and value.
*
*
The name must conform to RFC 2109. However, vendors may
* provide a configuration option that allows cookie names conforming
* to the original Netscape Cookie Specification to be accepted.
*
*
The name of a cookie cannot be changed once the cookie has
* been created.
*
*
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
* setValue method.
*
*
By default, cookies are created according to the Netscape
* cookie specification. The version can be changed with the
* setVersion method.
*
* @param name the name of the cookie
*
* @param value the value of the cookie
*
* @throws IllegalArgumentException if the cookie name is null or
* empty or contains any illegal characters (for example, a comma,
* space, or semicolon) or matches a token reserved for use by the
* cookie protocol
*
* @see #setValue
* @see #setVersion
*/
public Cookie(String name, String value) {
if (name == null || name.length() == 0) {
throw new IllegalArgumentException(
lStrings.getString("err.cookie_name_blank"));
}
if (!isToken(name) ||
name.equalsIgnoreCase("Comment") || // rfc2019
name.equalsIgnoreCase("Discard") || // 2019++
name.equalsIgnoreCase("Domain") ||
name.equalsIgnoreCase("Expires") || // (old cookies)
name.equalsIgnoreCase("Max-Age") || // rfc2019
name.equalsIgnoreCase("Path") ||
name.equalsIgnoreCase("Secure") ||
name.equalsIgnoreCase("Version") ||
name.startsWith("$")) {
String errMsg = lStrings.getString("err.cookie_name_is_token");
Object[] errArgs = new Object[1];
errArgs[0] = name;
errMsg = MessageFormat.format(errMsg, errArgs);
throw new IllegalArgumentException(errMsg);
}
this.name = name;
this.value = value;
}
/**
* Specifies 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.
*
* @param purpose a String specifying the comment
* to display to the user
*
* @see #getComment
*/
public void setComment(String purpose) {
comment = purpose;
}
/**
* Returns the comment describing the purpose of this cookie, or
* null if the cookie has no comment.
*
* @return the comment of the cookie, or null if unspecified
*
* @see #setComment
*/
public String getComment() {
return comment;
}
/**
*
* Specifies 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 not
* a.b.foo.com). By default, cookies are only returned
* to the server that sent them.
*
* @param domain the domain name within which this cookie is visible;
* form is according to RFC 2109
*
* @see #getDomain
*/
public void setDomain(String domain) {
this.domain = domain.toLowerCase(Locale.ENGLISH); // IE allegedly needs this
}
/**
* Gets the domain name of this Cookie.
*
*
Domain names are formatted according to RFC 2109.
*
* @return the domain name of this Cookie
*
* @see #setDomain
*/
public String getDomain() {
return domain;
}
/**
* Sets the maximum age in seconds for this Cookie.
*
*
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.
*
* @param 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 #getMaxAge
*/
public void setMaxAge(int expiry) {
maxAge = expiry;
}
/**
* Gets the maximum age in seconds of this Cookie.
*
*
By default, -1 is returned, which indicates that
* the cookie will persist until browser shutdown.
*
* @return an integer specifying the maximum age of the
* cookie in seconds; if negative, means
* the cookie persists until browser shutdown
*
* @see #setMaxAge
*/
public int getMaxAge() {
return maxAge;
}
/**
* Specifies 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.
*
*
* @param uri a String specifying a path
*
* @see #getPath
*/
public void setPath(String uri) {
path = uri;
}
/**
* Returns the path on the server
* to which the browser returns this cookie. The
* cookie is visible to all subpaths on the server.
*
* @return a String specifying a path that contains
* a servlet name, for example, /catalog
*
* @see #setPath
*/
public String getPath() {
return path;
}
/**
* 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.
*
* @param 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 #getSecure
*/
public void setSecure(boolean flag) {
secure = flag;
}
/**
* Returns true if the browser is sending cookies
* only over a secure protocol, or false if the
* browser can send cookies using any protocol.
*
* @return true if the browser uses a secure protocol,
* false otherwise
*
* @see #setSecure
*/
public boolean getSecure() {
return secure;
}
/**
* Returns the name of the cookie. The name cannot be changed after
* creation.
*
* @return the name of the cookie
*/
public String getName() {
return name;
}
/**
* Assigns a new value to this Cookie.
*
*
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.
*
* @param newValue the new value of the cookie
*
* @see #getValue
*/
public void setValue(String newValue) {
value = newValue;
}
/**
* Gets the current value of this Cookie.
*
* @return the current value of this Cookie
*
* @see #setValue
*/
public String getValue() {
return value;
}
/**
* 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.
*
* @return 0 if the cookie complies with the
* original Netscape specification; 1
* if the cookie complies with RFC 2109
*
* @see #setVersion
*/
public int getVersion() {
return version;
}
/**
* Sets the version of the cookie protocol that 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.
*
* @param v 0 if the cookie should comply with the original Netscape
* specification; 1 if the cookie should comply with RFC 2109
*
* @see #getVersion
*/
public void setVersion(int v) {
version = v;
}
/*
* Tests a string and returns true if the string counts as a
* reserved token in the Java language.
*
* @param value the String to be tested
*
* @return true if the String is a reserved
* token; false otherwise
*/
private boolean isToken(String value) {
int len = value.length();
for (int i = 0; i < len; i++) {
char c = value.charAt(i);
if (c < 0x20 || c >= 0x7f || TSPECIALS.indexOf(c) != -1) {
return false;
}
}
return true;
}
/**
* Overrides the standard java.lang.Object.clone
* method to return a copy of this Cookie.
*/
public Object clone() {
try {
return super.clone();
} catch (CloneNotSupportedException e) {
throw new RuntimeException(e.getMessage());
}
}
/**
* Marks or unmarks this Cookie as HttpOnly.
*
*
If isHttpOnly is set to true, this cookie is
* marked as HttpOnly, by adding the HttpOnly attribute
* to it.
*
*
HttpOnly cookies are not supposed to be exposed to
* client-side scripting code, and may therefore help mitigate certain
* kinds of cross-site scripting attacks.
*
* @param isHttpOnly true if this cookie is to be marked as
* HttpOnly, false otherwise
*
* @since Servlet 3.0
*/
public void setHttpOnly(boolean isHttpOnly) {
this.isHttpOnly = isHttpOnly;
}
/**
* Checks whether this Cookie has been marked as HttpOnly.
*
* @return true if this Cookie has been marked as HttpOnly,
* false otherwise
*
* @since Servlet 3.0
*/
public boolean isHttpOnly() {
return isHttpOnly;
}
}