1 /*
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   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
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  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
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  17  * You should have received a copy of the GNU General Public License version
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  25 
  26 /**
  27  * Interfaces used to model elements of the Java programming language.
  28  *
  29  * The term "element" in this package is used to refer to program
  30  * elements, the declared entities that make up a program.  Elements
  31  * include classes, interfaces, methods, constructors, and fields.
  32  * The interfaces in this package do not model the structure of a
  33  * program inside a method body; for example there is no
  34  * representation of a {@code for} loop or {@code try}-{@code finally}
  35  * block.  However, the interfaces can model some structures only
  36  * appearing inside method bodies, such as local variables and
  37  * anonymous classes.
  38  *
  39  * <p>When used in the context of annotation processing, an accurate
  40  * model of the element being represented must be returned.  As this
  41  * is a language model, the source code provides the fiducial
  42  * (reference) representation of the construct in question rather than
  43  * a representation in an executable output like a class file.
  44  * Executable output may serve as the basis for creating a modeling
  45  * element.  However, the process of translating source code to
  46  * executable output may not permit recovering some aspects of the
  47  * source code representation.  For example, annotations with
  48  * {@linkplain java.lang.annotation.RetentionPolicy#SOURCE source}
  49  * {@linkplain java.lang.annotation.Retention retention} cannot be
  50  * recovered from class files and class files might not be able to
  51  * provide source position information.
  52  *
  53  * Names of parameters may not be recoverable from class files.
  54  *
  55  * The {@linkplain javax.lang.model.element.Modifier modifiers} on an
  56  * element created from a class file may differ in some cases from an
  57  * element for the same declaration created from a source file
  58  * including:
  59  *
  60  * <ul>
  61  * <li> {@code strictfp} on a class or interface
  62  * <li> {@code final} on a parameter
  63  * <li> {@code protected}, {@code private}, and {@code static} on classes and interfaces
  64  * </ul>
  65  *
  66  * Some elements which are {@linkplain
  67  * javax.lang.model.util.Elements.Origin#MANDATED mandated} may not be
  68  * marked as such when created from class files.
  69  *
  70  * Additionally, {@linkplain
  71  * javax.lang.model.util.Elements.Origin#SYNTHETIC synthetic}
  72  * constructs in a class file, such as accessor methods used in
  73  * implementing nested classes and {@linkplain
  74  * javax.lang.model.util.Elements.Origin#isBridge(ExecutableElement)
  75  * bridge methods} used in implementing covariant returns, are
  76  * translation artifacts strictly outside of this model. However, when
  77  * operating on class files, it is helpful be able to operate on such
  78  * elements, screening them out when appropriate.
  79  *
  80  * <p>During annotation processing, operating on incomplete or
  81  * erroneous programs is necessary; however, there are fewer
  82  * guarantees about the nature of the resulting model.  If the source
  83  * code is not syntactically well-formed or has some other
  84  * irrecoverable error that could not be removed by the generation of
  85  * new types, a model may or may not be provided as a quality of
  86  * implementation issue.
  87  * If a program is syntactically valid but erroneous in some other
  88  * fashion, any returned model must have no less information than if
  89  * all the method bodies in the program were replaced by {@code "throw
  90  * new RuntimeException();"}.  If a program refers to a missing type Xyz,
  91  * the returned model must contain no less information than if the
  92  * declaration of type Xyz were assumed to be {@code "class Xyz {}"},
  93  * {@code "interface Xyz {}"}, {@code "enum Xyz {}"}, or {@code
  94  * "@interface Xyz {}"}. If a program refers to a missing type {@code
  95  * Xyz<K1, ... ,Kn>}, the returned model must contain no less
  96  * information than if the declaration of Xyz were assumed to be
  97  * {@code "class Xyz<T1, ... ,Tn> {}"} or {@code "interface Xyz<T1,
  98  * ... ,Tn> {}"}
  99  *
 100  * <p> Unless otherwise specified in a particular implementation, the
 101  * collections returned by methods in this package should be expected
 102  * to be unmodifiable by the caller and unsafe for concurrent access.
 103  *
 104  * <p> Unless otherwise specified, methods in this package will throw
 105  * a {@code NullPointerException} if given a {@code null} argument.
 106  *
 107  * @author Joseph D. Darcy
 108  * @author Scott Seligman
 109  * @author Peter von der Ah&eacute;
 110  * @see javax.lang.model.util.Elements
 111  * @since 1.6
 112  */
 113 package javax.lang.model.element;