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  25 
  26 /**
  27  * <h1>The JAXB 2.0 runtime</h1>.
  28  *
  29  * <h1>Overview</h1>
  30  * <p>
  31  * This module provides code that implements {@link javax.xml.bind.JAXBContext}.
  32  * Roughly speaking the runtime works like this:
  33  *
  34  * <ol>
  35  *  <li>There's a set of classes and interfaces that model JAXB-bound types.
  36  *      You can think of this as a reflection library for JAXB.
  37  *  <li>There's a set of classes that constitute the unmarshaller and marshaller.
  38  *      Each class represents a small portion, and they are composed to perform
  39  *      the operations.
  40  *  <li>{@link com.sun.xml.internal.bind.v2.runtime.JAXBContextImpl} builds itself by reading the model and
  41  *      composing unmarshallers and marshallers.
  42  * </ol>
  43  *
  44  * <h1>Interesting Pieces inside Runtime</h1>
  45  * <p>
  46  * The followings are the interesting pieces inside the runtime.
  47  *
  48  * <dl>
  49  *  <dt>{@link com.sun.xml.internal.bind.v2.model model}
  50  *  <dd>
  51  *    This set of classes and interfaces models JAXB-bound types.
  52  *
  53  *  <dt>{@link com.sun.xml.internal.bind.v2.runtime XML I/O}
  54  *  <dd>
  55  *    This set of classes implements the JAXB API and provides the XML I/O functionality.
  56  * </dl>
  57  *
  58  * <p>
  59  * The classes <b>NOT</b> in the {@link com.sun.xml.internal.bind.v2} package (and its subpackages)
  60  * are also used by old JAXB 1.0 clients.
  61  *
  62  * <h1>Models</h1>
  63  * <p>
  64  * "Model" is the portion of the code that represents JAXB-bound types.
  65  *
  66  * <p>
  67  * The following picture illustrates the relationship among major
  68  * packages of the binding model.
  69  *
  70  * <div>
  71  *   <img src="doc-files/packages.png" alt="">
  72  * </div>
  73  *
  74  * <p>
  75  * The core model contracts are all interfaces, and they are parameterized
  76  * so that they can be used
  77  * with different reflection libraries. This is necessary, as the model
  78  * is used:
  79  * <ol>
  80  *  <li> at runtime to process loaded classes,
  81  *  <li> at tool-time to process source files / class files, and
  82  *  <li> at schema compile time to generate source code.
  83  * </ol>
  84  * They all use different reflection libraries.
  85  *
  86  * <p>
  87  * This portion is used by all
  88  * three running mode of JAXB.
  89  * <a href="model/impl/package-summary.html">The corresponding base-level implementaion</a>
  90  * is also parameterized.
  91  *
  92  * <p>
  93  * The runtime model contract and implementation are used only at the run-time.
  94  * These packages fix the parameterization to the Java reflection,
  95  * and also exposes additional functionalities to actually do the
  96  * unmarshalling/marshalling. These classes have "Runtime" prefix.
  97  *
  98  * <p>
  99  * Finally XJC has its own implementation of the contract in
 100  * its own package. This package also fixes the parameterization
 101  * to its own reflection library.
 102  *
 103  * <p>
 104  * When you work on the code, it is often helpful to know the layer you are in.
 105  *
 106  *
 107  * <p>
 108  * The binding model design roughly looks like the following.
 109  * For more details, see the javadoc of each component.
 110  *
 111  * <div>
 112  *  <img src="doc-files/j2s_architecture.gif" alt="">
 113  * </div>
 114  *
 115  * <b><i>TODO: link to classes from above pictures</i></b>
 116  *
 117  *
 118  * <h2>Evolution Rules</h2>
 119  * None of the class in this package or below should be directly
 120  * referenced by the generated code. Hence they can be changed freely
 121  * from versions to versions.
 122  *
 123  *
 124  *
 125  *
 126  * <h1>Performance Characteristics</h1>
 127  * <p>
 128  * Model construction happens inside {@link javax.xml.bind.JAXBContext#newInstance(Class[])}.
 129  * It's desirable for this step to be fast and consume less memory,
 130  * but it's not too performance sensitive.
 131  *
 132  * <p>
 133  * Code that implements the unmarshaller and the marshaller OTOH
 134  * needs to be very carefully written to achieve maximum sustaining
 135  * performance.
 136  *
 137  *
 138  *
 139  *
 140  * <h1>Bootstrap Sequence</h1>
 141  * <p>
 142  * The following picture illustrates how the {@link javax.xml.bind.JAXBContext#newInstance(Class[])} method
 143  * triggers activities.
 144  *
 145  */
 146 package com.sun.xml.internal.bind.v2;