1 /* 2 * Copyright (c) 1997, 2013, 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 com.sun.xml.internal.ws.api.server; 27 28 import java.util.Collection; 29 import java.util.Collections; 30 import java.util.Set; 31 import java.util.concurrent.CopyOnWriteArraySet; 32 33 import com.sun.istack.internal.NotNull; 34 import com.sun.xml.internal.ws.api.Component; 35 import com.sun.xml.internal.ws.api.ComponentEx; 36 import com.sun.xml.internal.ws.api.ComponentRegistry; 37 38 /** 39 * Root of the SPI implemented by the container 40 * (such as application server.) 41 * 42 * <p> 43 * Often technologies that are built on top of JAX-WS 44 * (such as Tango) needs to negotiate private contracts between 45 * them and the container. This interface allows such technologies 46 * to query the negotiated SPI by using the {@link #getSPI(Class)}. 47 * 48 * <p> 49 * For example, if a security pipe needs to get some information 50 * from a container, they can do the following: 51 * <ol> 52 * <li>Negotiate an interface with the container and define it. 53 * (let's call it {@code ContainerSecuritySPI}.) 54 * <li>The container will implement {@code ContainerSecuritySPI}. 55 * <li>At the runtime, a security pipe gets 56 * {@link WSEndpoint} and then to {@link Container}. 57 * <li>It calls {@code container.getSPI(ContainerSecuritySPI.class)} 58 * <li>The container returns an instance of {@code ContainerSecuritySPI}. 59 * <li>The security pipe talks to the container through this SPI. 60 * </ol> 61 * 62 * <p> 63 * This protects JAX-WS from worrying about the details of such contracts, 64 * while still providing the necessary service of hooking up those parties. 65 * 66 * <p> 67 * Technologies that run inside JAX-WS server runtime can access this object through 68 * {@link WSEndpoint#getContainer()}. In the client runtime, it can be accessed from 69 * {@link ContainerResolver#getContainer()} 70 * 71 * @author Kohsuke Kawaguchi 72 * @see WSEndpoint 73 */ 74 public abstract class Container implements ComponentRegistry, ComponentEx { 75 private final Set<Component> components = new CopyOnWriteArraySet<Component>(); 76 77 /** 78 * For derived classes. 79 */ 80 protected Container() { 81 } 82 83 /** 84 * Constant that represents a "no {@link Container}", 85 * which always returns null from {@link #getSPI(Class)}. 86 */ 87 public static final Container NONE = new NoneContainer(); 88 89 private static final class NoneContainer extends Container { 90 } 91 92 public <S> S getSPI(Class<S> spiType) { 93 if (components == null) return null; 94 for (Component c : components) { 95 S s = c.getSPI(spiType); 96 if (s != null) 97 return s; 98 } 99 return null; 100 } 101 102 public Set<Component> getComponents() { 103 return components; 104 } 105 106 public @NotNull <E> Iterable<E> getIterableSPI(Class<E> spiType) { 107 E item = getSPI(spiType); 108 if (item != null) { 109 Collection<E> c = Collections.singletonList(item); 110 return c; 111 } 112 return Collections.emptySet(); 113 } 114 }