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/**
* <h1>The JAXB 2.0 runtime</h1>.
*
* <h1>Overview</h1>
* <p>
* This module provides code that implements {@link JAXBContext}.
* Roughly speaking the runtime works like this:
*
* <ol>
* <li>There's a set of classes and interfaces that model JAXB-bound types.
* You can think of this as a reflection library for JAXB.
* <li>There's a set of classes that constitute the unmarshaller and marshaller.
* Each class represents a small portion, and they are composed to perform
* the operations.
* <li>{@link JAXBContextImpl} builds itself by reading the model and
* composing unmarshallers and marshallers.
* </ol>
*
* <h1>Interesting Pieces inside Runtime</h1>
* <p>
* The followings are the interesting pieces inside the runtime.
*
* <dl>
* <dt>{@link com.sun.xml.internal.bind.v2.model model}
* <dd>
* This set of classes and interfaces models JAXB-bound types.
*
* <dt>{@link com.sun.xml.internal.bind.v2.runtime XML I/O}
* <dd>
* This set of classes implements the JAXB API and provides the XML I/O functionality.
* </dl>
*
* <p>
* The classes <b>NOT</b> in the {@link com.sun.xml.internal.bind.v2} package (and its subpackages)
* are also used by old JAXB 1.0 clients.
*
* <h1>Models</h1>
* <p>
* "Model" is the portion of the code that represents JAXB-bound types.
*
* <p>
* The following picture illustrates the relationship among major
* packages of the binding model.
*
* <div>
* <img src="doc-files/packages.png"/>
* </div>
*
* <p>
* The core model contracts are all interfaces, and they are parameterized
* so that they can be used
* with different reflection libraries. This is necessary, as the model
* is used:
* <ol>
* <li> at runtime to process loaded classes,
* <li> at tool-time to process source files / class files, and
* <li> at schema compile time to generate source code.
* </ol>
* They all use different reflection libraries.
*
* <p>
* This portion is used by all
* three running mode of JAXB.
* <a href="model/impl/package-summary.html">The corresponding base-level implementaion</a>
* is also parameterized.
*
* <p>
* The runtime model contract and implementation are used only at the run-time.
* These packages fix the parameterization to the Java reflection,
* and also exposes additional functionalities to actually do the
* unmarshalling/marshalling. These classes have "Runtime" prefix.
*
* <p>
* Finally XJC has its own implementation of the contract in
* its own package. This package also fixes the parameterization
* to its own reflection library.
*
* <p>
* When you work on the code, it is often helpful to know the layer you are in.
*
*
* <p>
* The binding model design roughly looks like the following.
* For more details, see the javadoc of each component.
*
* <div>
* <img src="doc-files/j2s_architecture.gif"/>
* </div>
*
* <b><i>TODO: link to classes from above pictures</i></b>
*
*
* <h3>Evolution Rules</h3>
* None of the class in this package or below should be directly
* referenced by the generated code. Hence they can be changed freely
* from versions to versions.
*
*
*
*
* <h1>Performance Characteristics</h1>
* <p>
* Model construction happens inside {@link JAXBContext#newInstance(Class[])}.
* It's desirable for this step to be fast and consume less memory,
* but it's not too performance sensitive.
*
* <p>
* Code that implements the unmarshaller and the marshaller OTOH
* needs to be very carefully written to achieve maximum sustaining
* performance.
*
*
*
*
* <h1>Bootstrap Sequence</h1>
* <p>
* The following picture illustrates how the {@link JAXBContext#newInstance(Class[])} method
* triggers activities.
*
* {@SequenceDiagram
boxwid=1.2;
pobject(U,"user");
object(A,"JAXB API");
object(CF,"ContextFactory");
pobject(JC);
step();
message(U,A,"JAXBContext.newInstance()");
active(A);
message(A,A,"locate JAXB RI 2.0");
active(A);
step();
inactive(A);
message(A,CF,"createContext");
active(CF);
create_message(CF,JC,"c:JAXBContextImpl");
active(JC);
message(JC,JC,"build runtime model");
message(JC,JC,"build JaxBeanInfos");
inactive(JC);
rmessage(A,U,"return c");
inactive(CF);
inactive(A);
complete(JC);
complete(CF);
complete(A);
* }
*
* @ArchitectureDocument
*/
package com.sun.xml.internal.bind.v2;