/*
 * Copyright 2002-2018 the original author or authors.
 *
 * 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.springframework.http.server.reactive;

import java.util.AbstractSet;
import java.util.Collection;
import java.util.Iterator;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.stream.Collectors;

import io.netty.handler.codec.http.HttpHeaders;

import org.springframework.lang.Nullable;
import org.springframework.util.MultiValueMap;

MultiValueMap implementation for wrapping Netty HTTP headers.
Author:Brian Clozel
Since:5.1.1
/** * {@code MultiValueMap} implementation for wrapping Netty HTTP headers. * * @author Brian Clozel * @since 5.1.1 */
class NettyHeadersAdapter implements MultiValueMap<String, String> { private final HttpHeaders headers; NettyHeadersAdapter(HttpHeaders headers) { this.headers = headers; } @Override @Nullable public String getFirst(String key) { return this.headers.get(key); } @Override public void add(String key, @Nullable String value) { this.headers.add(key, value); } @Override public void addAll(String key, List<? extends String> values) { this.headers.add(key, values); } @Override public void addAll(MultiValueMap<String, String> values) { values.forEach(this.headers::add); } @Override public void set(String key, @Nullable String value) { this.headers.set(key, value); } @Override public void setAll(Map<String, String> values) { values.forEach(this.headers::set); } @Override public Map<String, String> toSingleValueMap() { Map<String, String> singleValueMap = new LinkedHashMap<>(this.headers.size()); this.headers.entries() .forEach(entry -> { if (!singleValueMap.containsKey(entry.getKey())) { singleValueMap.put(entry.getKey(), entry.getValue()); } }); return singleValueMap; } @Override public int size() { return this.headers.names().size(); } @Override public boolean isEmpty() { return this.headers.isEmpty(); } @Override public boolean containsKey(Object key) { return (key instanceof String && this.headers.contains((String) key)); } @Override public boolean containsValue(Object value) { return (value instanceof String && this.headers.entries().stream() .anyMatch(entry -> value.equals(entry.getValue()))); } @Override @Nullable public List<String> get(Object key) { if (containsKey(key)) { return this.headers.getAll((String) key); } return null; } @Nullable @Override public List<String> put(String key, @Nullable List<String> value) { List<String> previousValues = this.headers.getAll(key); this.headers.set(key, value); return previousValues; } @Nullable @Override public List<String> remove(Object key) { if (key instanceof String) { List<String> previousValues = this.headers.getAll((String) key); this.headers.remove((String) key); return previousValues; } return null; } @Override public void putAll(Map<? extends String, ? extends List<String>> map) { map.forEach(this.headers::add); } @Override public void clear() { this.headers.clear(); } @Override public Set<String> keySet() { return this.headers.names(); } @Override public Collection<List<String>> values() { return this.headers.names().stream() .map(this.headers::getAll).collect(Collectors.toList()); } @Override public Set<Entry<String, List<String>>> entrySet() { return new AbstractSet<Entry<String, List<String>>>() { @Override public Iterator<Entry<String, List<String>>> iterator() { return new EntryIterator(); } @Override public int size() { return headers.size(); } }; } @Override public String toString() { return org.springframework.http.HttpHeaders.formatHeaders(this); } private class EntryIterator implements Iterator<Entry<String, List<String>>> { private Iterator<String> names = headers.names().iterator(); @Override public boolean hasNext() { return this.names.hasNext(); } @Override public Entry<String, List<String>> next() { return new HeaderEntry(this.names.next()); } } private class HeaderEntry implements Entry<String, List<String>> { private final String key; HeaderEntry(String key) { this.key = key; } @Override public String getKey() { return this.key; } @Override public List<String> getValue() { return headers.getAll(this.key); } @Override public List<String> setValue(List<String> value) { List<String> previousValues = headers.getAll(this.key); headers.set(this.key, value); return previousValues; } } }