/** * 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 org.apache.camel.component.undertow; import java.util.ArrayList; import java.util.List; import java.util.Map; /** * Util class for useful methods used all over the component */ public final class UndertowUtils { private UndertowUtils() { } public static void appendHeader(Map<String, Object> headers, String key, Object value) { if (headers.containsKey(key)) { Object existing = headers.get(key); List<Object> list; if (existing instanceof List) { list = (List<Object>) existing; } else { list = new ArrayList<Object>(); list.add(existing); } list.add(value); value = list; } headers.put(key, value); } }