1 /*
   2  * Copyright (c) 2005, 2015, 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
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   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
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  25 
  26 /**
  27  * Provides the API for creating and building SOAP messages. This package
  28  * is defined in the <i>SOAP with Attachments API for Java<sup><font size="-2">TM</font></sup>
  29  * (SAAJ) 1.4</i> specification.
  30  *
  31  * <p> The API in the <code>javax.xml.soap</code> package allows you to do the following:
  32  *
  33  * <ul>
  34  *     <li>create a point-to-point connection to a specified endpoint
  35  *     <li>create a SOAP message
  36  *     <li>create an XML fragment
  37  *     <li>add content to the header of a SOAP message
  38  *     <li>add content to the body of a SOAP message
  39  *     <li>create attachment parts and add content to them
  40  *     <li>access/add/modify parts of a SOAP message
  41  *     <li>create/add/modify SOAP fault information
  42  *     <li>extract content from a SOAP message
  43  *     <li>send a SOAP request-response message
  44  * </ul>
  45  *
  46  * <p>
  47  * In addition the APIs in the <code>javax.xml.soap</code> package extend
  48  * their  counterparts in the <code>org.w3c.dom</code> package. This means that
  49  * the  <code>SOAPPart</code> of a <code>SOAPMessage</code> is also a DOM Level
  50  * 2 <code>Document</code>, and can be manipulated as such by applications,
  51  * tools and libraries that use DOM (see http://www.w3.org/DOM/ for more information).
  52  * It is important to note that, while it is possible to use DOM APIs to add
  53  * ordinary DOM nodes to a SAAJ tree, the SAAJ APIs are still required to return
  54  * SAAJ types when examining or manipulating the tree. In order to accomplish
  55  * this the SAAJ APIs (specifically {@link javax.xml.soap.SOAPElement#getChildElements()})
  56  * are allowed to silently replace objects that are incorrectly typed relative
  57  * to SAAJ requirements with equivalent objects of the required type. These
  58  * replacements must never cause the logical structure of the tree to change,
  59  * so from the perspective of the DOM APIs the tree will remain unchanged. However,
  60  * the physical composition of the tree will have changed so that references
  61  * to the nodes that were replaced will refer to nodes that are no longer a
  62  * part of the tree. The SAAJ APIs are not allowed to make these replacements
  63  * if they are not required so the replacement objects will never subsequently
  64  * be silently replaced by future calls to the SAAJ API.
  65  * <p>
  66  * What this means in practical terms is that an application that starts to use
  67  * SAAJ APIs on a tree after manipulating it using DOM APIs must assume that the
  68  * tree has been translated into an all SAAJ tree and that any references to objects
  69  * within the tree that were obtained using DOM APIs are no longer valid. Switching
  70  * from SAAJ APIs to DOM APIs is not allowed to cause invalid references and
  71  * neither is using SAAJ APIs exclusively. It is only switching from using DOM
  72  * APIs on a particular SAAJ tree to using SAAJ APIs that causes the risk of
  73  * invalid references.
  74  *
  75  * <h3>Discovery of SAAJ implementation</h3>
  76  * <p>
  77  * There are several factories defined in the SAAJ API to discover and load specific implementation:
  78  *
  79  * <ul>
  80  *     <li>{@link javax.xml.soap.SOAPFactory}
  81  *     <li>{@link javax.xml.soap.MessageFactory}
  82  *     <li>{@link javax.xml.soap.SOAPConnectionFactory}
  83  *     <li>{@link javax.xml.soap.SAAJMetaFactory}
  84  * </ul>
  85  *
  86  * First three define {@code newInstance()} method which uses a common lookup procedure to determine
  87  * the implementation class:
  88  *
  89  * <ul>
  90  *  <li>Checks if a system property with the same name as the factory class is set (e.g.
  91  *  {@code javax.xml.soap.SOAPFactory}). If such property exists then its value is assumed to be the fully qualified
  92  *  name of the implementation class. This phase of the look up enables per-JVM override of the SAAJ implementation.
  93  *  <li>Use the configuration file "jaxm.properties". The file is in standard
  94  *  {@link java.util.Properties} format and typically located in the
  95  *  {@code conf} directory of the Java installation. It contains the fully qualified
  96  *  name of the implementation class with the key being the system property
  97  *  defined above.
  98  *  <li> Use the service-provider loading facilities, defined by the {@link java.util.ServiceLoader} class,
  99  *  to attempt to locate and load an implementation of the service using the {@linkplain
 100  *  java.util.ServiceLoader#load(java.lang.Class) default loading mechanism}.
 101  *  <li> Finally, if all the steps above fail, {@link javax.xml.soap.SAAJMetaFactory} instance is used
 102  *  to locate specific implementation (for {@link javax.xml.soap.MessageFactory} and {@link javax.xml.soap.SOAPFactory})
 103  *  or platform default implementation is used ({@link javax.xml.soap.SOAPConnectionFactory}).
 104  *  Whenever {@link javax.xml.soap.SAAJMetaFactory} is used, its lookup procedure to get actual instance is performed.
 105  * </ul>
 106  */
 107 package javax.xml.soap;