| /* |
| * Copyright (c) 1997, 2012, 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 |
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| |
| package com.sun.xml.internal.ws.api.pipe; |
| |
| import com.sun.xml.internal.ws.api.message.Message; |
| import com.sun.xml.internal.ws.api.message.Packet; |
| import com.sun.xml.internal.ws.api.pipe.helper.AbstractFilterPipeImpl; |
| import com.sun.xml.internal.ws.api.pipe.helper.AbstractPipeImpl; |
| |
| import javax.annotation.PreDestroy; |
| import javax.xml.ws.Dispatch; |
| import javax.xml.ws.Provider; |
| import javax.xml.ws.WebServiceException; |
| import javax.xml.ws.handler.Handler; |
| import javax.xml.ws.handler.LogicalHandler; |
| import javax.xml.ws.handler.MessageContext; |
| import javax.xml.ws.handler.soap.SOAPHandler; |
| |
| /** |
| * Abstraction of the intermediate layers in the processing chain |
| * and transport. |
| * |
| * <h2>What is a {@link Pipe}?</h2> |
| * <p> |
| * Transport is a kind of pipe. It sends the {@link Packet} |
| * through, say, HTTP connection, and receives the data back into another {@link Packet}. |
| * |
| * <p> |
| * More often, a pipe is a filter. It acts on a packet, |
| * and then it passes the packet into another pipe. It can |
| * do the same on the way back. |
| * |
| * <p> |
| * For example, XWSS will be a {@link Pipe} |
| * that delegates to another {@link Pipe}, and it can wrap a {@link Packet} into |
| * another {@link Packet} to encrypt the body and add a header, for example. |
| * |
| * <p> |
| * Yet another kind of filter pipe is those that wraps {@link LogicalHandler} |
| * and {@link SOAPHandler}. These pipes are heavy-weight; they often consume |
| * a message in a packet and create a new one, and then pass it to the next pipe. |
| * For performance reason it probably makes sense to have one {@link Pipe} |
| * instance that invokes a series of {@link LogicalHandler}s, another one |
| * for {@link SOAPHandler}. |
| * |
| * <p> |
| * There would be a {@link Pipe} implementation that invokes {@link Provider}. |
| * There would be a {@link Pipe} implementation that invokes a service method |
| * on the user's code. |
| * There would be a {@link Dispatch} implementation that invokes a {@link Pipe}. |
| * |
| * <p> |
| * WS-MEX can be implemented as a {@link Pipe} that looks for |
| * {@link Message#getPayloadNamespaceURI()} and serves the request. |
| * |
| * |
| * <h2>Pipe Lifecycle</h2> |
| * {@link Pipe}line is expensive to set up, so once it's created it will be reused. |
| * A {@link Pipe}line is not reentrant; one pipeline is used to process one request/response |
| * at at time. The same pipeline instance may serve request/response for different threads, |
| * if one comes after another and they don't overlap. |
| * <p> |
| * Where a need arises to process multiple requests concurrently, a pipeline |
| * gets cloned through {@link PipeCloner}. Note that this need may happen on |
| * both server (because it quite often serves multiple requests concurrently) |
| * and client (because it needs to support asynchronous method invocations.) |
| * <p> |
| * Created pipelines (including cloned ones and the original) may be discarded and GCed |
| * at any time at the discretion of whoever owns pipelines. Pipes can, however, expect |
| * at least one copy (or original) of pipeline to live at any given time while a pipeline |
| * owner is interested in the given pipeline configuration (in more concerete terms, |
| * for example, as long as a dispatch object lives, it's going to keep at least one |
| * copy of a pipeline alive.) |
| * <p> |
| * Before a pipeline owner dies, it may invoke {@link #preDestroy()} on the last |
| * remaining pipeline. It is "may" for pipeline owners that live in the client-side |
| * of JAX-WS (such as dispatches and proxies), but it is a "must" for pipeline owners |
| * that live in the server-side of JAX-WS. |
| * <p> |
| * This last invocation gives a chance for some pipes to clean up any state/resource |
| * acquired (such as WS-RM's sequence, WS-Trust's SecurityToken), although as stated above, |
| * this is not required for clients. |
| * |
| * |
| * |
| * <h2>Pipe and State</h2> |
| * <p> |
| * The lifecycle of pipelines is designed to allow a {@link Pipe} to store various |
| * state in easily accessible fashion. |
| * |
| * |
| * <h3>Per-packet state</h3> |
| * <p> |
| * Any information that changes from a packet to packet should be |
| * stored in {@link Packet}. This includes information like |
| * transport-specific headers. |
| * |
| * <h3>Per-thread state</h3> |
| * <p> |
| * Any expensive objects that are non-reentrant can be stored in |
| * instance variables of a {@link Pipe}, since {@link #process(Packet)} is |
| * non reentrant. When a pipe is copied, new instances should be allocated |
| * so that two {@link Pipe} instances don't share thread-unsafe resources. |
| * This includes things like canonicalizers, JAXB unmarshallers, buffers, |
| * and so on. |
| * |
| * <h3>Per-proxy/per-endpoint state</h3> |
| * <p> |
| * Information that is tied to a particular proxy/dispatch can be stored |
| * in a separate object that is referenced from a pipe. When |
| * a new pipe is copied, you can simply hand out a reference to the newly |
| * created one, so that all copied pipes refer to the same instance. |
| * See the following code as an example: |
| * |
| * <pre> |
| * class PipeImpl { |
| * // this object stores per-proxy state |
| * class DataStore { |
| * int counter; |
| * } |
| * |
| * private DataStore ds; |
| * |
| * // create a fresh new pipe |
| * public PipeImpl(...) { |
| * .... |
| * ds = new DataStore(); |
| * } |
| * |
| * // copy constructor |
| * private PipeImpl(PipeImpl that, PipeCloner cloner) { |
| * cloner.add(that,this); |
| * ... |
| * this.ds = that.ds; |
| * } |
| * |
| * public PipeImpl copy(PipeCloner pc) { |
| * return new PipeImpl(this,pc); |
| * } |
| * } |
| * </pre> |
| * |
| * <p> |
| * Note that access to such resource often needs to be synchronized, |
| * since multiple copies of pipelines may execute concurrently. |
| * |
| * <p> |
| * If such information is read-only, |
| * it can be stored as instance variables of a pipe, |
| * and its reference copied as pipes get copied. (The only difference between |
| * this and per-thread state is that you just won't allocate new things when |
| * pipes get copied here.) |
| * |
| * |
| * <h3>VM-wide state</h3> |
| * <p> |
| * <tt>static</tt> is always there for you to use. |
| * |
| * |
| * |
| * <h2>Pipes and Handlers</h2> |
| * <p> |
| * JAX-WS has a notion of {@link LogicalHandler} and {@link SOAPHandler}, and |
| * we intend to have one {@link Pipe} implementation that invokes all the |
| * {@link LogicalHandler}s and another {@link Pipe} implementation that invokes |
| * all the {@link SOAPHandler}s. Those implementations need to convert a {@link Message} |
| * into an appropriate format, but grouping all the handlers together eliminates |
| * the intermediate {@link Message} instanciation between such handlers. |
| * <p> |
| * This grouping also allows such implementations to follow the event notifications |
| * to handlers (i.e. {@link Handler#close(MessageContext)} method. |
| * |
| * |
| * <pre> |
| * TODO: Possible types of pipe: |
| * creator: create message from wire |
| * to SAAJ SOAP message |
| * to cached representation |
| * directly to JAXB beans |
| * transformer: transform message from one representation to another |
| * JAXB beans to encoded SOAP message |
| * StAX writing + JAXB bean to encoded SOAP message |
| * modifier: modify message |
| * add SOAP header blocks |
| * security processing |
| * header block processor: |
| * process certain SOAP header blocks |
| * outbound initiator: input from the client |
| * Manage input e.g. JAXB beans and associated with parts of the SOAP message |
| * inbound invoker: invoke the service |
| * Inkoke SEI, e.g. EJB or SEI in servlet. |
| * </pre> |
| * |
| * @see AbstractPipeImpl |
| * @see AbstractFilterPipeImpl |
| * @deprecated |
| * Use {@link Tube}. |
| */ |
| public interface Pipe { |
| /** |
| * Sends a {@link Packet} and returns a response {@link Packet} to it. |
| * |
| * @throws WebServiceException |
| * On the server side, this signals an error condition where |
| * a fault reply is in order (or the exception gets eaten by |
| * the top-most transport {@link Pipe} if it's one-way.) |
| * This frees each {@link Pipe} from try/catching a |
| * {@link WebServiceException} in every layer. |
| * |
| * Note that this method is also allowed to return a {@link Packet} |
| * that has a fault as the payload. |
| * |
| * <p> |
| * On the client side, the {@link WebServiceException} thrown |
| * will be propagated all the way back to the calling client |
| * applications. (The consequence of that is that if you are |
| * a filtering {@link Pipe}, you must not catch the exception |
| * that your next {@link Pipe} threw. |
| * |
| * @throws RuntimeException |
| * Other runtime exception thrown by this method must |
| * be treated as a bug in the pipe implementation, |
| * and therefore should not be converted into a fault. |
| * (Otherwise it becomes very difficult to debug implementation |
| * problems.) |
| * |
| * <p> |
| * On the server side, this exception should be most likely |
| * just logged. On the client-side it gets propagated to the |
| * client application. |
| * |
| * <p> |
| * The consequence of this is that if a pipe calls |
| * into an user application (such as {@link SOAPHandler} |
| * or {@link LogicalHandler}), where a {@link RuntimeException} |
| * is *not* a bug in the JAX-WS implementation, it must be catched |
| * and wrapped into a {@link WebServiceException}. |
| * |
| * @param request |
| * The packet that represents a request message. Must not be null. |
| * If the packet has a non-null message, it must be a valid |
| * unconsumed {@link Message}. This message represents the |
| * SOAP message to be sent as a request. |
| * <p> |
| * The packet is also allowed to carry no message, which indicates |
| * that this is an output-only request. |
| * (that's called "solicit", right? - KK) |
| * |
| * @return |
| * The packet that represents a response message. Must not be null. |
| * If the packet has a non-null message, it must be |
| * a valid unconsumed {@link Message}. This message represents |
| * a response to the request message passed as a parameter. |
| * <p> |
| * The packet is also allowed to carry no message, which indicates |
| * that there was no response. This is used for things like |
| * one-way message and/or one-way transports. |
| */ |
| Packet process( Packet request); |
| |
| /** |
| * Invoked before the last copy of the pipeline is about to be discarded, |
| * to give {@link Pipe}s a chance to clean up any resources. |
| * |
| * <p> |
| * This can be used to invoke {@link PreDestroy} lifecycle methods |
| * on user handler. The invocation of it is optional on the client side, |
| * but mandatory on the server side. |
| * |
| * <p> |
| * When multiple copies of pipelines are created, this method is called |
| * only on one of them. |
| * |
| * @throws WebServiceException |
| * If the clean up fails, {@link WebServiceException} can be thrown. |
| * This exception will be propagated to users (if this is client), |
| * or recorded (if this is server.) |
| */ |
| void preDestroy(); |
| |
| /** |
| * Creates an identical clone of this {@link Pipe}. |
| * |
| * <p> |
| * This method creates an identical pipeline that can be used |
| * concurrently with this pipeline. When the caller of a pipeline |
| * is multi-threaded and need concurrent use of the same pipeline, |
| * it can do so by creating copies through this method. |
| * |
| * <h3>Implementation Note</h3> |
| * <p> |
| * It is the implementation's responsibility to call |
| * {@link PipeCloner#add(Pipe,Pipe)} to register the copied pipe |
| * with the original. This is required before you start copying |
| * the other {@link Pipe} references you have, or else there's a |
| * risk of infinite recursion. |
| * <p> |
| * For most {@link Pipe} implementations that delegate to another |
| * {@link Pipe}, this method requires that you also copy the {@link Pipe} |
| * that you delegate to. |
| * <p> |
| * For limited number of {@link Pipe}s that do not maintain any |
| * thread unsafe resource, it is allowed to simply return <tt>this</tt> |
| * from this method (notice that even if you are stateless, if you |
| * got a delegating {@link Pipe} and that one isn't stateless, you |
| * still have to copy yourself.) |
| * |
| * <p> |
| * Note that this method might be invoked by one thread while another |
| * thread is executing the {@link #process(Packet)} method. See |
| * the {@link Codec#copy()} for more discussion about this. |
| * |
| * @param cloner |
| * Use this object (in particular its {@link PipeCloner#copy(Pipe)} method |
| * to clone other pipe references you have |
| * in your pipe. See {@link PipeCloner} for more discussion |
| * about why. |
| * |
| * @return |
| * always non-null {@link Pipe}. |
| */ |
| Pipe copy(PipeCloner cloner); |
| } |