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25 
26 package javax.lang.model.element;
27 
28 import javax.lang.model.util.Elements;
29 import javax.lang.model.type.TypeMirror;
30 import javax.lang.model.type.TypeKind;
31 
32 /**
33  * Represents a field, {@code enum} constant, method or constructor
34  * parameter, local variable, resource variable, or exception
35  * parameter.
36  *
37  * @author Joseph D. Darcy
38  * @author Scott Seligman
39  * @author Peter von der Ahé
40  * @since 1.6
41  */
42 public interface VariableElement extends Element {
43     /**
44      * {@return the type of this variable}
45      *
46      * Note that the types of variables range over {@linkplain
47      * TypeKind many kinds} of types, including primitive types,
48      * declared types, and array types, among others.
49      *
50      * @see TypeKind
51      */
52     @Override
asType()53     TypeMirror asType();
54 
55     /**
56      * Returns the value of this variable if this is a {@code final}
57      * field initialized to a compile-time constant.  Returns {@code
58      * null} otherwise.  The value will be of a primitive type or a
59      * {@code String}.  If the value is of a primitive type, it is
60      * wrapped in the appropriate wrapper class (such as {@link
61      * Integer}).
62      *
63      * <p>Note that not all {@code final} fields will have
64      * constant values.  In particular, {@code enum} constants are
65      * <em>not</em> considered to be compile-time constants.  To have a
66      * constant value, a field's type must be either a primitive type
67      * or {@code String}.
68      *
69      * @return the value of this variable if this is a {@code final}
70      * field initialized to a compile-time constant, or {@code null}
71      * otherwise
72      *
73      * @see Elements#getConstantExpression(Object)
74      * @jls 15.29 Constant Expressions
75      * @jls 4.12.4 final Variables
76      */
getConstantValue()77     Object getConstantValue();
78 
79     /**
80      * {@return the simple name of this variable element}
81      *
82      * <p>For method and constructor parameters, the name of each
83      * parameter must be distinct from the names of all other
84      * parameters of the same executable.  If the original source
85      * names are not available, an implementation may synthesize names
86      * subject to the distinctness requirement above.
87      */
88     @Override
getSimpleName()89     Name getSimpleName();
90 
91     /**
92      * {@return the enclosing element of this variable}
93      *
94      * The enclosing element of a method or constructor parameter is
95      * the executable declaring the parameter.
96      */
97     @Override
getEnclosingElement()98     Element getEnclosingElement();
99 }
100