jaxb-ri/runtime/impl/src/main/java/org/glassfish/jaxb/runtime/v2/package-info.java

/*
 * Copyright (c) 1997, 2021 Oracle and/or its affiliates. All rights reserved.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Distribution License v. 1.0, which is available at
 * http://www.eclipse.org/org/documents/edl-v10.php.
 *
 * SPDX-License-Identifier: BSD-3-Clause
 */

/**
 * <h2>The JAXB 2.0 runtime</h2>.
 *
 * <h2>Overview</h2>
 * <p>
 * This module provides code that implements {@link jakarta.xml.bind.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 org.glassfish.jaxb.runtime.v2.runtime.JAXBContextImpl} builds itself by reading the model and
 *      composing unmarshallers and marshallers.
 * </ol>
 *
 * <h2>Interesting Pieces inside Runtime</h2>
 * <p>
 * The followings are the interesting pieces inside the runtime.
 *
 * <dl>
 *  <dt>{@code org.glassfish.jaxb.core.v2.model model}
 *  <dd>
 *    This set of classes and interfaces models JAXB-bound types.
 *
 *  <dt>{@link org.glassfish.jaxb.core.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 org.glassfish.jaxb.core.v2} package (and its subpackages)
 * are also used by old JAXB 1.0 clients.
 *
 * <h2>Models</h2>
 * <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" alt="">
 * </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" alt="">
 * </div>
 *
 * <b><i>TODO: link to classes from above pictures</i></b>
 *
 *
 * <h2>Evolution Rules</h2>
 * 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.
 *
 *
 *
 *
 * <h2>Performance Characteristics</h2>
 * <p>
 * Model construction happens inside {@link jakarta.xml.bind.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.
 *
 *
 *
 *
 * <h2>Bootstrap Sequence</h2>
 * <p>
 * The following picture illustrates how the {@link jakarta.xml.bind.JAXBContext#newInstance(Class[])} method
 * triggers activities.
 *
 */
package org.glassfish.jaxb.runtime.v2;