/*
* Copyright (c) 2005, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
package com.sun.net.httpserver;
import java.util.*;
import java.io.*;
/**
* HTTP request and response headers are represented by this class which implements
* the interface {@link java.util.Map}<
* {@link java.lang.String},{@link java.util.List}<{@link java.lang.String}>>.
* The keys are case-insensitive Strings representing the header names and
* the value associated with each key is a {@link List}<{@link String}> with one
* element for each occurence of the header name in the request or response.
* <p>
* For example, if a response header instance contains one key "HeaderName" with two values "value1 and value2"
* then this object is output as two header lines:
* <blockquote><pre>
* HeaderName: value1
* HeaderName: value2
* </blockquote></pre>
* <p>
* All the normal {@link java.util.Map} methods are provided, but the following
* additional convenience methods are most likely to be used:
* <ul>
* <li>{@link #getFirst(String)} returns a single valued header or the first value of
* a multi-valued header.</li>
* <li>{@link #add(String,String)} adds the given header value to the list for the given key</li>
* <li>{@link #set(String,String)} sets the given header field to the single value given
* overwriting any existing values in the value list.
* </ul><p>
* All methods in this class accept <code>null</code> values for keys and values. However, null
* keys will never will be present in HTTP request headers, and will not be output/sent in response headers.
* Null values can be represented as either a null entry for the key (i.e. the list is null) or
* where the key has a list, but one (or more) of the list's values is null. Null values are output
* as a header line containing the key but no associated value.
* @since 1.6
*/
public class Headers implements Map<String,List<String>> {
HashMap<String,List<String>> map;
public Headers () {map = new HashMap<String,List<String>>(32);}
/* Normalize the key by converting to following form.
* First char upper case, rest lower case.
* key is presumed to be ASCII
*/
private String normalize (String key) {
if (key == null) {
return null;
}
int len = key.length();
if (len == 0) {
return key;
}
char[] b = new char [len];
String s = null;
b = key.toCharArray();
if (b[0] >= 'a' && b[0] <= 'z') {
b[0] = (char)(b[0] - ('a' - 'A'));
}
for (int i=1; i<len; i++) {
if (b[i] >= 'A' && b[i] <= 'Z') {
b[i] = (char) (b[i] + ('a' - 'A'));
}
}
s = new String (b);
return s;
}
public int size() {return map.size();}
public boolean isEmpty() {return map.isEmpty();}
public boolean containsKey(Object key) {
if (key == null) {
return false;
}
if (!(key instanceof String)) {
return false;
}
return map.containsKey (normalize((String)key));
}
public boolean containsValue(Object value) {
return map.containsValue(value);
}
public List<String> get(Object key) {
return map.get(normalize((String)key));
}
/**
* returns the first value from the List of String values
* for the given key (if at least one exists).
* @param key the key to search for
* @return the first string value associated with the key
*/
public String getFirst (String key) {
List<String> l = map.get(normalize((String)key));
if (l == null) {
return null;
}
return l.get(0);
}
public List<String> put(String key, List<String> value) {
return map.put (normalize(key), value);
}
/**
* adds the given value to the list of headers
* for the given key. If the mapping does not
* already exist, then it is created
* @param key the header name
* @param value the header value to add to the header
*/
public void add (String key, String value) {
String k = normalize(key);
List<String> l = map.get(k);
if (l == null) {
l = new LinkedList<String>();
map.put(k,l);
}
l.add (value);
}
/**
* sets the given value as the sole header value
* for the given key. If the mapping does not
* already exist, then it is created
* @param key the header name
* @param value the header value to set.
*/
public void set (String key, String value) {
LinkedList<String> l = new LinkedList<String>();
l.add (value);
put (key, l);
}
public List<String> remove(Object key) {
return map.remove(normalize((String)key));
}
public void putAll(Map<? extends String,? extends List<String>> t) {
map.putAll (t);
}
public void clear() {map.clear();}
public Set<String> keySet() {return map.keySet();}
public Collection<List<String>> values() {return map.values();}
public Set<Map.Entry<String, List<String>>> entrySet() {
return map.entrySet();
}
public boolean equals(Object o) {return map.equals(o);}
public int hashCode() {return map.hashCode();}
}