Cookie.java
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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 jakarta.servlet.http;
import java.io.Serializable;
import java.text.MessageFormat;
import java.util.BitSet;
import java.util.Collections;
import java.util.Locale;
import java.util.Map;
import java.util.ResourceBundle;
import java.util.TreeMap;
/**
* 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.
* <p>
* 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.
* <p>
* 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 50 cookies
* for each domain, 3000 cookies total, and may limit cookie size to 4 KiB each.
* <p>
* 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.
* <p>
* 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.
* <p>
* This class supports both the RFC 6265 specification.
*/
public class Cookie implements Cloneable, Serializable {
private static final String LSTRING_FILE = "jakarta.servlet.http.LocalStrings";
private static final ResourceBundle LSTRINGS = ResourceBundle.getBundle(LSTRING_FILE);
private static final CookieNameValidator validation = new RFC6265Validator();
private static final long serialVersionUID = 2L;
/**
* Cookie name.
*/
private final String name;
/**
* Cookie value.
*/
private String value;
/**
* Attributes encoded in the header's cookie fields.
*/
private volatile Map<String,String> attributes;
private static final String DOMAIN = "Domain";
private static final String MAX_AGE = "Max-Age";
private static final String PATH = "Path";
private static final String SECURE = "Secure";
private static final String HTTP_ONLY = "HttpOnly";
/**
* Constructs a cookie with a specified name and value.
* <p>
* The cookie's name cannot be changed after creation.
* <p>
* 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 <code>setValue</code> method.
*
* @param name a <code>String</code> specifying the name of the cookie
* @param value a <code>String</code> specifying the value of the cookie
*
* @throws IllegalArgumentException if the cookie name contains illegal characters
*
* @see #setValue
*/
public Cookie(String name, String value) {
validation.validate(name);
this.name = name;
this.value = value;
}
/**
* If called, this method has no effect.
*
* @param purpose ignored
*
* @see #getComment
*
* @deprecated This is no longer required with RFC 6265
*/
@Deprecated(since = "Servlet 6.0", forRemoval = true)
public void setComment(String purpose) {
// NO-OP
}
/**
* With the adoption of support for RFC 6265, this method should no longer be used.
*
* @return always {@code null}
*
* @see #setComment
*
* @deprecated This is no longer required with RFC 6265
*/
@Deprecated(since = "Servlet 6.0", forRemoval = true)
public String getComment() {
return null;
}
/**
* Specifies the domain within which this cookie should be presented.
* <p>
* By default, cookies are only returned to the server that sent them.
*
* @param pattern a <code>String</code> containing the domain name within which this cookie is visible
*
* @see #getDomain
*/
public void setDomain(String pattern) {
if (pattern == null) {
setAttributeInternal(DOMAIN, null);
} else {
// IE requires the domain to be lower case (unconfirmed)
setAttributeInternal(DOMAIN, pattern.toLowerCase(Locale.ENGLISH));
}
}
/**
* Returns the domain name set for this cookie.
*
* @return a <code>String</code> containing the domain name
*
* @see #setDomain
*/
public String getDomain() {
return getAttribute(DOMAIN);
}
/**
* Sets the maximum age of the cookie in seconds.
* <p>
* A positive value indicates that the cookie will expire after that many seconds have passed. Note that the value
* is the <i>maximum</i> age when the cookie will expire, not the cookie's current age.
* <p>
* 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) {
setAttributeInternal(MAX_AGE, Integer.toString(expiry));
}
/**
* Returns the maximum age of the cookie, specified in seconds, By default, <code>-1</code> indicating 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() {
String maxAge = getAttribute(MAX_AGE);
if (maxAge == null) {
return -1;
} else {
return Integer.parseInt(maxAge);
}
}
/**
* Specifies a path for the cookie to which the client should return the cookie.
* <p>
* 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, <i>/catalog</i>, which
* makes the cookie visible to all directories on the server under <i>/catalog</i>.
*
* @param uri a <code>String</code> specifying a path
*
* @see #getPath
*/
public void setPath(String uri) {
setAttributeInternal(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 <code>String</code> specifying a path that contains a servlet name, for example, <i>/catalog</i>
*
* @see #setPath
*/
public String getPath() {
return getAttribute(PATH);
}
/**
* Indicates to the browser whether the cookie should only be sent using a secure protocol, such as HTTPS or SSL.
* <p>
* The default value is <code>false</code>.
*
* @param flag if <code>true</code>, sends the cookie from the browser to the server only when using a secure
* protocol; if <code>false</code>, sent on any protocol
*
* @see #getSecure
*/
public void setSecure(boolean flag) {
setAttributeInternal(SECURE, Boolean.toString(flag));
}
/**
* Returns <code>true</code> if the browser is sending cookies only over a secure protocol, or <code>false</code> if
* the browser can send cookies using any protocol.
*
* @return <code>true</code> if the browser uses a secure protocol; otherwise, <code>false</code>
*
* @see #setSecure
*/
public boolean getSecure() {
return Boolean.parseBoolean(getAttribute(SECURE));
}
/**
* Returns the name of the cookie. The name cannot be changed after creation.
*
* @return a <code>String</code> specifying the cookie's name
*/
public String getName() {
return name;
}
/**
* Assigns a new value to a cookie after the cookie is created. If you use a binary value, you may want to use
* BASE64 encoding.
* <p>
* 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 a <code>String</code> specifying the new value
*
* @see #getValue
* @see Cookie
*/
public void setValue(String newValue) {
value = newValue;
}
/**
* Returns the value of the cookie.
*
* @return a <code>String</code> containing the cookie's present value
*
* @see #setValue
* @see Cookie
*/
public String getValue() {
return value;
}
/**
* With the adoption of support for RFC 6265, this method should no longer be used.
*
* @return Always zero
*
* @see #setVersion
*
* @deprecated This is no longer required with RFC 6265
*/
@Deprecated(since = "Servlet 6.0", forRemoval = true)
public int getVersion() {
return 0;
}
/**
* If called, this method has no effect.
*
* @param v Ignored
*
* @see #getVersion
*
* @deprecated This is no longer required with RFC 6265
*/
@Deprecated(since = "Servlet 6.0", forRemoval = true)
public void setVersion(int v) {
// NO-OP
}
/**
* Overrides the standard <code>java.lang.Object.clone</code> method to return a copy of this cookie.
*/
@Override
public Object clone() {
try {
return super.clone();
} catch (CloneNotSupportedException e) {
throw new RuntimeException(e);
}
}
/**
* Sets the flag that controls if this cookie will be hidden from scripts on the client side.
*
* @param httpOnly The new value of the flag
*
* @since Servlet 3.0
*/
public void setHttpOnly(boolean httpOnly) {
setAttributeInternal(HTTP_ONLY, Boolean.toString(httpOnly));
}
/**
* Gets the flag that controls if this cookie will be hidden from scripts on the client side.
*
* @return <code>true</code> if the cookie is hidden from scripts, else <code>false</code>
*
* @since Servlet 3.0
*/
public boolean isHttpOnly() {
return Boolean.parseBoolean(getAttribute(HTTP_ONLY));
}
/**
* Sets the value for the given cookie attribute. When a value is set via this method, the value returned by the
* attribute specific getter (if any) must be consistent with the value set via this method.
*
* @param name Name of attribute to set
* @param value Value of attribute
*
* @throws IllegalArgumentException If the attribute name is null or contains any characters not permitted for use
* in Cookie names.
* @throws NumberFormatException If the attribute is known to be numerical but the provided value cannot be
* parsed to a number.
*
* @since Servlet 6.0
*/
public void setAttribute(String name, String value) {
if (name == null) {
throw new IllegalArgumentException(LSTRINGS.getString("cookie.attribute.invalidName.null"));
}
if (!validation.isToken(name)) {
String msg = LSTRINGS.getString("cookie.attribute.invalidName.notToken");
throw new IllegalArgumentException(MessageFormat.format(msg, name));
}
if (name.equalsIgnoreCase(MAX_AGE)) {
if (value == null) {
setAttributeInternal(MAX_AGE, null);
} else {
// Integer.parseInt throws NFE if required
setMaxAge(Integer.parseInt(value));
}
} else {
setAttributeInternal(name, value);
}
}
private void setAttributeInternal(String name, String value) {
if (attributes == null) {
if (value == null) {
return;
} else {
// Case insensitive keys but retain case used
attributes = new TreeMap<>(String.CASE_INSENSITIVE_ORDER);
}
}
if (value == null) {
attributes.remove(name);
} else {
attributes.put(name, value);
}
}
/**
* Obtain the value for a given attribute. Values returned from this method must be consistent with the values set
* and returned by the attribute specific getters and setters in this class.
*
* @param name Name of attribute to return
*
* @return Value of specified attribute
*
* @since Servlet 6.0
*/
public String getAttribute(String name) {
if (attributes == null) {
return null;
} else {
return attributes.get(name);
}
}
/**
* Obtain the Map of attributes and values (excluding version) for this cookie.
*
* @return A read-only Map of attributes to values, excluding version.
*
* @since Servlet 6.0
*/
public Map<String,String> getAttributes() {
if (attributes == null) {
return Collections.emptyMap();
} else {
return Collections.unmodifiableMap(attributes);
}
}
@Override
public int hashCode() {
final int prime = 31;
int result = 1;
result = prime * result + ((attributes == null) ? 0 : attributes.hashCode());
result = prime * result + ((name == null) ? 0 : name.hashCode());
result = prime * result + ((value == null) ? 0 : value.hashCode());
return result;
}
@Override
public boolean equals(Object obj) {
if (this == obj) {
return true;
}
if (obj == null) {
return false;
}
if (getClass() != obj.getClass()) {
return false;
}
Cookie other = (Cookie) obj;
if (attributes == null) {
if (other.attributes != null) {
return false;
}
} else if (!attributes.equals(other.attributes)) {
return false;
}
if (name == null) {
if (other.name != null) {
return false;
}
} else if (!name.equals(other.name)) {
return false;
}
if (value == null) {
if (other.value != null) {
return false;
}
} else if (!value.equals(other.value)) {
return false;
}
return true;
}
}
class CookieNameValidator {
private static final String LSTRING_FILE = "jakarta.servlet.http.LocalStrings";
protected static final ResourceBundle lStrings = ResourceBundle.getBundle(LSTRING_FILE);
protected final BitSet allowed;
protected CookieNameValidator(String separators) {
allowed = new BitSet(128);
allowed.set(0x20, 0x7f); // any CHAR except CTLs or separators
for (int i = 0; i < separators.length(); i++) {
char ch = separators.charAt(i);
allowed.clear(ch);
}
}
void validate(String name) {
if (name == null || name.length() == 0) {
throw new IllegalArgumentException(lStrings.getString("err.cookie_name_blank"));
}
if (!isToken(name)) {
String errMsg = lStrings.getString("err.cookie_name_is_token");
throw new IllegalArgumentException(MessageFormat.format(errMsg, name));
}
}
boolean isToken(String possibleToken) {
int len = possibleToken.length();
for (int i = 0; i < len; i++) {
char c = possibleToken.charAt(i);
if (!allowed.get(c)) {
return false;
}
}
return true;
}
}
class RFC6265Validator extends CookieNameValidator {
private static final String RFC2616_SEPARATORS = "()<>@,;:\\\"/[]?={} \t";
RFC6265Validator() {
super(RFC2616_SEPARATORS);
}
}