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/*
* Copyright (c) 2005, 2017, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
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*/
/**
* Interfaces used to model elements of the Java programming language.
*
* The term "element" in this package is used to refer to program
* elements, the declared entities that make up a program. Elements
* include classes, interfaces, methods, constructors, and fields.
* The interfaces in this package do not model the structure of a
* program inside a method body; for example there is no
* representation of a {@code for} loop or {@code try}-{@code finally}
* block. However, the interfaces can model some structures only
* appearing inside method bodies, such as local variables and
* anonymous classes.
*
* <p>When used in the context of annotation processing, an accurate
* model of the element being represented must be returned. As this
* is a language model, the source code provides the fiducial
* (reference) representation of the construct in question rather than
* a representation in an executable output like a class file.
* Executable output may serve as the basis for creating a modeling
* element. However, the process of translating source code to
* executable output may not permit recovering some aspects of the
* source code representation. For example, annotations with
* {@linkplain java.lang.annotation.RetentionPolicy#SOURCE source}
* {@linkplain java.lang.annotation.Retention retention} cannot be
* recovered from class files and class files might not be able to
* provide source position information.
*
* Names of parameters may not be recoverable from class files.
*
* The {@linkplain javax.lang.model.element.Modifier modifiers} on an
* element created from a class file may differ in some cases from an
* element for the same declaration created from a source file
* including:
*
* <ul>
* <li> {@code strictfp} on a class or interface
* <li> {@code final} on a parameter
* <li> {@code protected}, {@code private}, and {@code static} on classes and interfaces
* </ul>
*
* Some elements which are {@linkplain
* javax.lang.model.util.Elements.Origin#MANDATED mandated} may not be
* marked as such when created from class files.
*
* Additionally, {@linkplain
* javax.lang.model.util.Elements.Origin#SYNTHETIC synthetic}
* constructs in a class file, such as accessor methods used in
* implementing nested classes and {@linkplain
* javax.lang.model.util.Elements.Origin#isBridge(ExecutableElement)
* bridge methods} used in implementing covariant returns, are
* translation artifacts strictly outside of this model. However, when
* operating on class files, it is helpful be able to operate on such
* elements, screening them out when appropriate.
*
* <p>During annotation processing, operating on incomplete or
* erroneous programs is necessary; however, there are fewer
* guarantees about the nature of the resulting model. If the source
* code is not syntactically well-formed or has some other
* irrecoverable error that could not be removed by the generation of
* new types, a model may or may not be provided as a quality of
* implementation issue.
* If a program is syntactically valid but erroneous in some other
* fashion, any returned model must have no less information than if
* all the method bodies in the program were replaced by {@code "throw
* new RuntimeException();"}. If a program refers to a missing type Xyz,
* the returned model must contain no less information than if the
* declaration of type Xyz were assumed to be {@code "class Xyz {}"},
* {@code "interface Xyz {}"}, {@code "enum Xyz {}"}, or {@code
* "@interface Xyz {}"}. If a program refers to a missing type {@code
* Xyz<K1, ... ,Kn>}, the returned model must contain no less
* information than if the declaration of Xyz were assumed to be
* {@code "class Xyz<T1, ... ,Tn> {}"} or {@code "interface Xyz<T1,
* ... ,Tn> {}"}
*
* <p> Unless otherwise specified in a particular implementation, the
* collections returned by methods in this package should be expected
* to be unmodifiable by the caller and unsafe for concurrent access.
*
* <p> Unless otherwise specified, methods in this package will throw
* a {@code NullPointerException} if given a {@code null} argument.
*
* @author Joseph D. Darcy
* @author Scott Seligman
* @author Peter von der Ah&eacute;
* @since 1.6
*/
package javax.lang.model.element;