org.simpleframework.http.message.MessageHeader Maven / Gradle / Ivy
Show all versions of simple-http Show documentation
/*
* Message.java February 2007
*
* Copyright (C) 2007, Niall Gallagher
*
* 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 org.simpleframework.http.message;
import java.util.LinkedList;
import java.util.List;
import org.simpleframework.common.KeyMap;
import org.simpleframework.http.Cookie;
import org.simpleframework.http.parse.DateParser;
import org.simpleframework.http.parse.ValueParser;
/**
* The Message object is used to store an retrieve the
* headers for both a request and response. Headers are stored and
* retrieved in a case insensitive manner according to RFC 2616.
* The message also allows multiple header values to be added to a
* single header name, headers such as Cookie and Set-Cookie can be
* added multiple times with different values.
*
* @author Niall Gallagher
*/
public class MessageHeader implements Message {
/**
* This is used to store the cookies added to the HTTP header.
*/
private final KeyMap cookies;
/**
* This is used to store multiple header values for a name.
*/
private final KeyMap values;
/**
* This is used to store the individual names for the header.
*/
private final KeyMap names;
/**
* This is used to parse all date headers added to the message.
*/
private final DateParser parser;
/**
* Constructor for the Message object. This is used
* to create a case insensitive means for storing HTTP header
* names and values. Dates can also be added to message as a
* long value and is converted to RFC 1123 compliant date string.
*/
public MessageHeader() {
this.cookies = new KeyMap();
this.values = new KeyMap();
this.names = new KeyMap();
this.parser = new DateParser();
}
/**
* This is used to acquire the names of the of the headers that
* have been set in the response. This can be used to acquire all
* header values by name that have been set within the response.
* If no headers have been set this will return an empty list.
*
* @return a list of strings representing the set header names
*/
public List getNames() {
return names.getValues();
}
/**
* This can be used to set a HTTP message header to this object.
* The name and value of the HTTP message header will be used to
* create a HTTP message header object which can be retrieved using
* the getValue in combination with the get methods.
* This will perform a remove using the issued header
* name before the header value is set.
*
* @param name the name of the HTTP message header to be added
* @param value the value the HTTP message header will have
*/
public void setValue(String name, String value) {
List list = getAll(name);
if(value == null) {
String token = name.toLowerCase();
values.remove(token);
names.remove(token);
} else {
list.clear();
list.add(value);
}
}
/**
* This can be used to set a HTTP message header to this object.
* The name and value of the HTTP message header will be used to
* create a HTTP message header object which can be retrieved using
* the getValue in combination with the get methods.
* This will perform a remove using the issued header
* name before the header value is set.
*
* @param name the name of the HTTP message header to be added
* @param value the value the HTTP message header will have
*/
public void setInteger(String name, int value) {
setValue(name, String.valueOf(value));
}
/**
* This can be used to set a HTTP message header to this object.
* The name and value of the HTTP message header will be used to
* create a HTTP message header object which can be retrieved using
* the getValue in combination with the get methods.
* This will perform a remove using the issued header
* name before the header value is set.
*
* @param name the name of the HTTP message header to be added
* @param value the value the HTTP message header will have
*/
public void setLong(String name, long value) {
setValue(name, String.valueOf(value));
}
/**
* This is used as a convenience method for adding a header that
* needs to be parsed into a HTTP date string. This will convert
* the date given into a date string defined in RFC 2616 sec 3.3.1.
* This will perform a remove using the issued header
* name before the header value is set.
*
* @param name the name of the HTTP message header to be added
* @param date the value constructed as an RFC 1123 date string
*/
public void setDate(String name, long date) {
setValue(name, parser.convert(date));
}
/**
* This can be used to add a HTTP message header to this object.
* The name and value of the HTTP message header will be used to
* create a HTTP message header object which can be retrieved using
* the getValue in combination with the get methods.
*
* @param name the name of the HTTP message header to be added
* @param value the value the HTTP message header will have
*/
public void addValue(String name, String value) {
List list = getAll(name);
if(value != null) {
list.add(value);
}
}
/**
* This can be used to add a HTTP message header to this object.
* The name and value of the HTTP message header will be used to
* create a HTTP message header object which can be retrieved using
* the getInteger in combination with the get methods.
*
* @param name the name of the HTTP message header to be added
* @param value the value the HTTP message header will have
*/
public void addInteger(String name, int value) {
addValue(name, String.valueOf(value));
}
/**
* This is used as a convenience method for adding a header that
* needs to be parsed into a HTTPdate string. This will convert
* the date given into a date string defined in RFC 2616 sec 3.3.1.
*
* @param name the name of the HTTP message header to be added
* @param date the value constructed as an RFC 1123 date string
*/
public void addDate(String name, long date) {
addValue(name, parser.convert(date));
}
/**
* This can be used to get the value of the first message header
* that has the specified name. This will return the full string
* representing the named header value. If the named header does
* not exist then this will return a null value.
*
* @param name the HTTP message header to get the value from
*
* @return this returns the value that the HTTP message header
*/
public String getValue(String name) {
return getValue(name, 0);
}
/**
* This can be used to get the value of the first message header
* that has the specified name. This will return the full string
* representing the named header value. If the named header does
* not exist then this will return a null value.
*
* @param name the HTTP message header to get the value from
* @param index this is the index to get the value from
*
* @return this returns the value that the HTTP message header
*/
public String getValue(String name, int index) {
List list = getAll(name);
if(list.size() > index) {
return list.get(index);
}
return null;
}
/**
* This can be used to get the value of the first message header
* that has the specified name. This will return the integer
* representing the named header value. If the named header does
* not exist then this will return a value of minus one, -1.
*
* @param name the HTTP message header to get the value from
*
* @return this returns the value that the HTTP message header
*/
public int getInteger(String name) {
String value = getValue(name);
if(value == null) {
return -1;
}
return Integer.parseInt(value);
}
/**
* This can be used to get the value of the first message header
* that has the specified name. This will return the long
* representing the named header value. If the named header does
* not exist then this will return a value of minus one, -1.
*
* @param name the HTTP message header to get the value from
*
* @return this returns the value that the HTTP message header
*/
public long getLong(String name) {
String value = getValue(name);
if(value == null) {
return -1L;
}
return Long.parseLong(value);
}
/**
* This can be used to get the value of the first message header
* that has the specified name. This will return the long value
* representing the named header value. If the named header does
* not exist then this will return a value of minus one, -1.
*
* @param name the HTTP message header to get the value from
*
* @return this returns the value that the HTTP message header
*/
public long getDate(String name) {
String value = getValue(name);
if(value == null) {
return -1;
}
return parser.convert(value);
}
/**
* This returns the Cookie object stored under the
* specified name. This is used to retrieve cookies that have been
* set with the setCookie methods. If the cookie does
* not exist under the specified name this will return null.
*
* @param name this is the name of the cookie to be retrieved
*
* @return returns the Cookie by the given name
*/
public Cookie getCookie(String name) {
return cookies.get(name);
}
/**
* This returns all Cookie objects stored under the
* specified name. This is used to retrieve cookies that have been
* set with the setCookie methods. If there are no
* cookies then this will return an empty list.
*
* @return returns all the Cookie in the response
*/
public List getCookies() {
return cookies.getValues();
}
/**
* The setCookie method is used to set a cookie value
* with the cookie name. This will add a cookie to the response
* stored under the name of the cookie, when this is committed it
* will be added as a Set-Cookie header to the resulting response.
* This is a convenience method that avoids cookie creation.
*
* @param name this is the cookie to be added to the response
* @param value this is the cookie value that is to be used
*
* @return returns the cookie that has been set in the response
*/
public Cookie setCookie(String name, String value) {
return setCookie(new Cookie(name, value, true));
}
/**
* The setCookie method is used to set a cookie value
* with the cookie name. This will add a cookie to the response
* stored under the name of the cookie, when this is committed it
* will be added as a Set-Cookie header to the resulting response.
*
* @param cookie this is the cookie to be added to the response
*
* @return returns the cookie that has been set in the response
*/
public Cookie setCookie(Cookie cookie) {
String name = cookie.getName();
if(name != null) {
cookies.put(name, cookie);
}
return cookie;
}
/**
* This can be used to get the values of HTTP message headers
* that have the specified name. This is a convenience method that
* will present that values as tokens extracted from the header.
* This has obvious performance benefits as it avoids having to
* deal with substring and trim calls.
*
* The tokens returned by this method are ordered according to
* there HTTP quality values, or "q" values, see RFC 2616 section
* 3.9. This also strips out the quality parameter from tokens
* returned. So "image/html; q=0.9" results in "image/html". If
* there are no "q" values present then order is by appearance.
*
* The result from this is either the trimmed header value, that
* is, the header value with no leading or trailing whitespace
* or an array of trimmed tokens ordered with the most preferred
* in the lower indexes, so index 0 is has highest preference.
*
* @param name the name of the headers that are to be retrieved
*
* @return ordered list of tokens extracted from the header(s)
*/
public List getValues(String name) {
return getValues(getAll(name));
}
/**
* This can be used to get the values of HTTP message headers
* that have the specified name. This is a convenience method that
* will present that values as tokens extracted from the header.
* This has obvious performance benefits as it avoids having to
* deal with substring and trim calls.
*
* The tokens returned by this method are ordered according to
* there HTTP quality values, or "q" values, see RFC 2616 section
* 3.9. This also strips out the quality parameter from tokens
* returned. So "image/html; q=0.9" results in "image/html". If
* there are no "q" values present then order is by appearance.
*
* The result from this is either the trimmed header value, that
* is, the header value with no leading or trailing whitespace
* or an array of trimmed tokens ordered with the most preferred
* in the lower indexes, so index 0 is has highest preference.
*
* @param list this is the list of individual header values
*
* @return ordered list of tokens extracted from the header(s)
*/
public List getValues(List list) {
return new ValueParser(list).list();
}
/**
* This is used to acquire all the individual header values from
* the message. The header values provided by this are unparsed
* and represent the actual string values that have been added to
* the message keyed by a given header name.
*
* @param name the name of the header to get the values for
*
* @return this returns a list of the values for the header name
*/
public List getAll(String name) {
String token = name.toLowerCase();
Series series = values.get(token);
if(series == null) {
return getAll(name, token);
}
return series.getValues();
}
/**
* This is used to acquire all the individual header values from
* the message. The header values provided by this are unparsed
* and represent the actual string values that have been added to
* the message keyed by a given header name.
*
* @param name the name of the header to get the values for
* @param token this provides a lower case version of the header
*
* @return this returns a list of the values for the header name
*/
private List getAll(String name, String token) {
Series series = new Series();
String value = names.get(token);
if(value == null) {
names.put(token, name);
}
values.put(token, series);
return series.getValues();
}
/**
* The Series object is used to represent a list of
* HTTP header value for a given name. It allows multiple values
* to exist for a given header, such as the Cookie header. Most
* entries will contain a single value.
*/
private class Series {
/**
* Contains the header values that belong to the entry name.
*/
private List value;
/**
* Constructor for the Entry object. The entry is
* created using the name of the HTTP header. Values can be
* added to the entry list in order to build up the header.
*/
public Series() {
this.value = new LinkedList();
}
/**
* This returns the list of header values associated with the
* header name. Each value is added as an individual header
* prefixed by the header name and a semicolon character.
*
* @return this returns the list of values for the header
*/
public List getValues() {
return value;
}
}
}