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1   /*
2    * Copyright (c) 2003, 2013, Oracle and/or its affiliates. All rights reserved.
3    * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4    *
5    * This code is free software; you can redistribute it and/or modify it
6    * under the terms of the GNU General Public License version 2 only, as
7    * published by the Free Software Foundation.  Oracle designates this
8    * particular file as subject to the "Classpath" exception as provided
9    * by Oracle in the LICENSE file that accompanied this code.
10   *
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).
16   *
17   * You should have received a copy of the GNU General Public License version
18   * 2 along with this work; if not, write to the Free Software Foundation,
19   * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20   *
21   * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22   * or visit www.oracle.com if you need additional information or have any
23   * questions.
24   */
25  
26  package sun.reflect.generics.repository;
27  
28  import sun.reflect.generics.factory.GenericsFactory;
29  import sun.reflect.generics.tree.ClassSignature;
30  import sun.reflect.generics.tree.TypeTree;
31  import sun.reflect.generics.visitor.Reifier;
32  import sun.reflect.generics.parser.SignatureParser;
33  import java.lang.reflect.Type;
34  
35  
36  /**
37   * This class represents the generic type information for a class.
38   * The code is not dependent on a particular reflective implementation.
39   * It is designed to be used unchanged by at least core reflection and JDI.
40   */
41  public class ClassRepository extends GenericDeclRepository<ClassSignature> {
42  
43      public static final ClassRepository NONE = ClassRepository.make("Ljava/lang/Object;", null);
44  
45      private Type superclass; // caches the generic superclass info
46      private Type[] superInterfaces; // caches the generic superinterface info
47  
48   // private, to enforce use of static factory
49      private ClassRepository(String rawSig, GenericsFactory f) {
50          super(rawSig, f);
51      }
52  
53      protected ClassSignature parse(String s) {
54          return SignatureParser.make().parseClassSig(s);
55      }
56  
57      /**
58       * Static factory method.
59       * @param rawSig - the generic signature of the reflective object
60       * that this repository is servicing
61       * @param f - a factory that will provide instances of reflective
62       * objects when this repository converts its AST
63       * @return a <tt>ClassRepository</tt> that manages the generic type
64       * information represented in the signature <tt>rawSig</tt>
65       */
66      public static ClassRepository make(String rawSig, GenericsFactory f) {
67          return new ClassRepository(rawSig, f);
68      }
69  
70      // public API
71   /*
72   * When queried for a particular piece of type information, the
73   * general pattern is to consult the corresponding cached value.
74   * If the corresponding field is non-null, it is returned.
75   * If not, it is created lazily. This is done by selecting the appropriate
76   * part of the tree and transforming it into a reflective object
77   * using a visitor.
78   * a visitor, which is created by feeding it the factory
79   * with which the repository was created.
80   */
81  
82      public Type getSuperclass(){
83          if (superclass == null) { // lazily initialize superclass
84              Reifier r = getReifier(); // obtain visitor
85              // Extract superclass subtree from AST and reify
86              getTree().getSuperclass().accept(r);
87              // extract result from visitor and cache it
88              superclass = r.getResult();
89              }
90          return superclass; // return cached result
91      }
92  
93      public Type[] getSuperInterfaces(){
94          if (superInterfaces == null) { // lazily initialize super interfaces
95              // first, extract super interface subtree(s) from AST
96              TypeTree[] ts  = getTree().getSuperInterfaces();
97              // create array to store reified subtree(s)
98              Type[] sis = new Type[ts.length];
99              // reify all subtrees
100             for (int i = 0; i < ts.length; i++) {
101                 Reifier r = getReifier(); // obtain visitor
102                 ts[i].accept(r);// reify subtree
103                 // extract result from visitor and store it
104                 sis[i] = r.getResult();
105             }
106             superInterfaces = sis; // cache overall result
107         }
108         return superInterfaces.clone(); // return cached result
109     }
110 }