1 /*
   2  * Copyright (c) 2015, 2018, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package jdk.internal.net.http;
  27 
  28 import java.util.ArrayList;
  29 import java.util.List;
  30 import java.util.Map;
  31 import java.util.Objects;
  32 import java.util.TreeMap;
  33 import java.util.function.BiPredicate;
  34 import java.util.function.Predicate;
  35 import java.net.http.HttpHeaders;
  36 import jdk.internal.net.http.common.HttpHeadersImpl;
  37 import jdk.internal.net.http.common.Utils;
  38 import static java.util.Collections.emptyMap;
  39 import static java.util.Collections.unmodifiableList;
  40 import static java.util.Collections.unmodifiableMap;
  41 import static java.util.Objects.requireNonNull;
  42 
  43 final class ImmutableHeaders extends HttpHeaders {
  44 
  45     private final Map<String, List<String>> map;
  46 
  47     public static ImmutableHeaders empty() {
  48         return of(emptyMap());
  49     }
  50 
  51     public static ImmutableHeaders of(Map<String, List<String>> src) {
  52         return of(src, x -> true);
  53     }
  54 
  55     public static ImmutableHeaders of(HttpHeaders headers) {
  56         return (headers instanceof ImmutableHeaders)
  57                 ? (ImmutableHeaders)headers
  58                 : of(headers.map());
  59     }
  60 
  61     static ImmutableHeaders validate(HttpHeaders headers) {
  62         if (headers instanceof ImmutableHeaders) {
  63             return of(headers);
  64         }
  65         if (headers instanceof HttpHeadersImpl) {
  66             return of(headers);
  67         }
  68         Map<String, List<String>> map = headers.map();
  69         return new ImmutableHeaders(map, Utils.VALIDATE_USER_HEADER);
  70     }
  71 
  72     public static ImmutableHeaders of(Map<String, List<String>> src,
  73                                       Predicate<? super String> keyAllowed) {
  74         requireNonNull(src, "src");
  75         requireNonNull(keyAllowed, "keyAllowed");
  76         return new ImmutableHeaders(src, headerAllowed(keyAllowed));
  77     }
  78 
  79     public static ImmutableHeaders of(Map<String, List<String>> src,
  80                                       BiPredicate<? super String, ? super List<String>> headerAllowed) {
  81         requireNonNull(src, "src");
  82         requireNonNull(headerAllowed, "headerAllowed");
  83         return new ImmutableHeaders(src, headerAllowed);
  84     }
  85 
  86     private ImmutableHeaders(Map<String, List<String>> src,
  87                              BiPredicate<? super String, ? super List<String>> headerAllowed) {
  88         Map<String, List<String>> m = new TreeMap<>(String.CASE_INSENSITIVE_ORDER);
  89         src.entrySet().stream()
  90                 .forEach(e -> addIfAllowed(e, headerAllowed, m));
  91         this.map = unmodifiableMap(m);
  92     }
  93 
  94     private static void addIfAllowed(Map.Entry<String, List<String>> e,
  95                                      BiPredicate<? super String, ? super List<String>> headerAllowed,
  96                                      Map<String, List<String>> map) {
  97         String key = e.getKey();
  98         List<String> values = unmodifiableValues(e.getValue());
  99         if (headerAllowed.test(key, values)) {
 100             map.put(key, values);
 101         }
 102     }
 103 
 104     private static List<String> unmodifiableValues(List<String> values) {
 105         return unmodifiableList(new ArrayList<>(Objects.requireNonNull(values)));
 106     }
 107 
 108     private static BiPredicate<String, List<String>> headerAllowed(Predicate<? super String> keyAllowed) {
 109         return (n,v) -> keyAllowed.test(n);
 110     }
 111 
 112     @Override
 113     public Map<String, List<String>> map() {
 114         return map;
 115     }
 116 }