TypeElement.java revision 2571:10fc81ac75b4
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25
26package javax.lang.model.element;
27
28import java.util.List;
29import javax.lang.model.type.*;
30import javax.lang.model.util.*;
31
32/**
33 * Represents a class or interface program element.  Provides access
34 * to information about the type and its members.  Note that an enum
35 * type is a kind of class and an annotation type is a kind of
36 * interface.
37 *
38 * <p> <a name="ELEM_VS_TYPE"></a>
39 * While a {@code TypeElement} represents a class or interface
40 * <i>element</i>, a {@link DeclaredType} represents a class
41 * or interface <i>type</i>, the latter being a use
42 * (or <i>invocation</i>) of the former.
43 * The distinction is most apparent with generic types,
44 * for which a single element can define a whole
45 * family of types.  For example, the element
46 * {@code java.util.Set} corresponds to the parameterized types
47 * {@code java.util.Set<String>} and {@code java.util.Set<Number>}
48 * (and many others), and to the raw type {@code java.util.Set}.
49 *
50 * <p> Each method of this interface that returns a list of elements
51 * will return them in the order that is natural for the underlying
52 * source of program information.  For example, if the underlying
53 * source of information is Java source code, then the elements will be
54 * returned in source code order.
55 *
56 * @author Joseph D. Darcy
57 * @author Scott Seligman
58 * @author Peter von der Ah&eacute;
59 * @see DeclaredType
60 * @since 1.6
61 */
62public interface TypeElement extends Element, Parameterizable, QualifiedNameable {
63    /**
64     * Returns the fields, methods, constructors, and member types
65     * that are directly declared in this class or interface.
66     *
67     * This includes any (implicit) default constructor and
68     * the implicit {@code values} and {@code valueOf} methods of an
69     * enum type.
70     *
71     * <p> Note that as a particular instance of the {@linkplain
72     * javax.lang.model.element general accuracy requirements} and the
73     * ordering behavior required of this interface, the list of
74     * enclosed elements will be returned in the natural order for the
75     * originating source of information about the type.  For example,
76     * if the information about the type is originating from a source
77     * file, the elements will be returned in source code order.
78     * (However, in that case the the ordering of synthesized
79     * elements, such as a default constructor, is not specified.)
80     *
81     * @return the enclosed elements in proper order, or an empty list if none
82     */
83    @Override
84    List<? extends Element> getEnclosedElements();
85
86    /**
87     * Returns the <i>nesting kind</i> of this type element.
88     *
89     * @return the nesting kind of this type element
90     */
91    NestingKind getNestingKind();
92
93    /**
94     * Returns the fully qualified name of this type element.
95     * More precisely, it returns the <i>canonical</i> name.
96     * For local and anonymous classes, which do not have canonical names,
97     * an empty name is returned.
98     *
99     * <p>The name of a generic type does not include any reference
100     * to its formal type parameters.
101     * For example, the fully qualified name of the interface
102     * {@code java.util.Set<E>} is "{@code java.util.Set}".
103     * Nested types use "{@code .}" as a separator, as in
104     * "{@code java.util.Map.Entry}".
105     *
106     * @return the fully qualified name of this class or interface, or
107     * an empty name if none
108     *
109     * @see Elements#getBinaryName
110     * @jls 6.7 Fully Qualified Names and Canonical Names
111     */
112    Name getQualifiedName();
113
114    /**
115     * Returns the simple name of this type element.
116     *
117     * For an anonymous class, an empty name is returned.
118     *
119     * @return the simple name of this class or interface,
120     * an empty name for an anonymous class
121     *
122     */
123    @Override
124    Name getSimpleName();
125
126    /**
127     * Returns the direct superclass of this type element.
128     * If this type element represents an interface or the class
129     * {@code java.lang.Object}, then a {@link NoType}
130     * with kind {@link TypeKind#NONE NONE} is returned.
131     *
132     * @return the direct superclass, or a {@code NoType} if there is none
133     */
134    TypeMirror getSuperclass();
135
136    /**
137     * Returns the interface types directly implemented by this class
138     * or extended by this interface.
139     *
140     * @return the interface types directly implemented by this class
141     * or extended by this interface, or an empty list if there are none
142     */
143    List<? extends TypeMirror> getInterfaces();
144
145    /**
146     * Returns the formal type parameters of this type element
147     * in declaration order.
148     *
149     * @return the formal type parameters, or an empty list
150     * if there are none
151     */
152    List<? extends TypeParameterElement> getTypeParameters();
153
154    /**
155     * Returns the package of a top-level type and returns the
156     * immediately lexically enclosing element for a {@linkplain
157     * NestingKind#isNested nested} type.
158     *
159     * @return the package of a top-level type, the immediately
160     * lexically enclosing element for a nested type
161     */
162    @Override
163    Element getEnclosingElement();
164}
165