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/*
* 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
*/
/**
* The JAXB 2.0 runtime
.
*
* Overview
*
* This module provides code that implements {@link javax.xml.bind.JAXBContext}.
* Roughly speaking the runtime works like this:
*
*
* - There's a set of classes and interfaces that model JAXB-bound types.
* You can think of this as a reflection library for JAXB.
*
- 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.
*
- {@link com.sun.xml.bind.v2.runtime.JAXBContextImpl} builds itself by reading the model and
* composing unmarshallers and marshallers.
*
*
* Interesting Pieces inside Runtime
*
* The followings are the interesting pieces inside the runtime.
*
*
* - {@code com.sun.xml.bind.v2.model model}
*
-
* This set of classes and interfaces models JAXB-bound types.
*
*
- {@link com.sun.xml.bind.v2.runtime XML I/O}
*
-
* This set of classes implements the JAXB API and provides the XML I/O functionality.
*
*
*
* The classes NOT in the {@link com.sun.xml.bind.v2} package (and its subpackages)
* are also used by old JAXB 1.0 clients.
*
*
Models
*
* "Model" is the portion of the code that represents JAXB-bound types.
*
*
* The following picture illustrates the relationship among major
* packages of the binding model.
*
*
*
*
*
*
* 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:
*
* - at runtime to process loaded classes,
*
- at tool-time to process source files / class files, and
*
- at schema compile time to generate source code.
*
* They all use different reflection libraries.
*
*
* This portion is used by all
* three running mode of JAXB.
* The corresponding base-level implementaion
* is also parameterized.
*
*
* 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.
*
*
* Finally XJC has its own implementation of the contract in
* its own package. This package also fixes the parameterization
* to its own reflection library.
*
*
* When you work on the code, it is often helpful to know the layer you are in.
*
*
*
* The binding model design roughly looks like the following.
* For more details, see the javadoc of each component.
*
*
*
*
*
* TODO: link to classes from above pictures
*
*
* Evolution Rules
* 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.
*
*
*
*
* Performance Characteristics
*
* Model construction happens inside {@link javax.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.
*
*
* Code that implements the unmarshaller and the marshaller OTOH
* needs to be very carefully written to achieve maximum sustaining
* performance.
*
*
*
*
*
Bootstrap Sequence
*
* The following picture illustrates how the {@link javax.xml.bind.JAXBContext#newInstance(Class[])} method
* triggers activities.
*
*/
package com.sun.xml.bind.v2;