1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one
3 * or more contributor license agreements. See the NOTICE file
4 * distributed with this work for additional information
5 * regarding copyright ownership. The ASF licenses this file
6 * to you under the Apache License, Version 2.0 (the
7 * "License"); you may not use this file except in compliance
8 * with the License. You may obtain a copy of the License at
9 *
10 * https://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing,
13 * software distributed under the License is distributed on an
14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15 * KIND, either express or implied. See the License for the
16 * specific language governing permissions and limitations
17 * under the License.
18 */
19 package org.apache.bcel.generic;
20
21 import org.apache.bcel.Const;
22 import org.apache.bcel.Repository;
23 import org.apache.bcel.classfile.JavaClass;
24 import org.apache.bcel.classfile.Utility;
25
26 /**
27 * Denotes reference such as {@link String}.
28 */
29 public class ObjectType extends ReferenceType {
30
31 /**
32 * Constructs a new instance.
33 *
34 * @param className fully qualified class name, for example {@link String}.
35 * @return a new instance.
36 * @since 6.0
37 */
38 public static ObjectType getInstance(final String className) {
39 return new ObjectType(className);
40 }
41
42 private final String className; // Class name of type
43
44 /**
45 * Constructs a new instance.
46 *
47 * @param className fully qualified class name, for example {@link String}.
48 */
49 public ObjectType(final String className) {
50 super(Const.T_REFERENCE, "L" + Utility.packageToPath(className) + ";");
51 this.className = Utility.pathToPackage(className);
52 }
53
54 /**
55 * Java Virtual Machine Specification edition 2, � 5.4.4 Access Control
56 *
57 * @throws ClassNotFoundException if the class referenced by this type can't be found
58 */
59 public boolean accessibleTo(final ObjectType accessor) throws ClassNotFoundException {
60 final JavaClass jc = Repository.lookupClass(className);
61 if (jc.isPublic()) {
62 return true;
63 }
64 final JavaClass acc = Repository.lookupClass(accessor.className);
65 return acc.getPackageName().equals(jc.getPackageName());
66 }
67
68 /**
69 * @return true if both type objects refer to the same class.
70 */
71 @Override
72 public boolean equals(final Object type) {
73 return type instanceof ObjectType && ((ObjectType) type).className.equals(className);
74 }
75
76 /**
77 * @return name of referenced class.
78 */
79 @Override
80 public String getClassName() {
81 return className;
82 }
83
84 /**
85 * @return a hash code value for the object.
86 */
87 @Override
88 public int hashCode() {
89 return className.hashCode();
90 }
91
92 /**
93 * If "this" doesn't reference a class, it references an interface or a non-existant entity.
94 *
95 * @deprecated (since 6.0) this method returns an inaccurate result if the class or interface referenced cannot be
96 * found: use referencesClassExact() instead
97 */
98 @Deprecated
99 public boolean referencesClass() {
100 try {
101 final JavaClass jc = Repository.lookupClass(className);
102 return jc.isClass();
103 } catch (final ClassNotFoundException e) {
104 return false;
105 }
106 }
107
108 /**
109 * Return true if this type references a class, false if it references an interface.
110 *
111 * @return true if the type references a class, false if it references an interface.
112 * @throws ClassNotFoundException if the class or interface referenced by this type can't be found
113 */
114 public boolean referencesClassExact() throws ClassNotFoundException {
115 final JavaClass jc = Repository.lookupClass(className);
116 return jc.isClass();
117 }
118
119 /**
120 * If "this" doesn't reference an interface, it references a class or a non-existant entity.
121 *
122 * @deprecated (since 6.0) this method returns an inaccurate result if the class or interface referenced cannot be
123 * found: use referencesInterfaceExact() instead
124 */
125 @Deprecated
126 public boolean referencesInterface() {
127 try {
128 final JavaClass jc = Repository.lookupClass(className);
129 return !jc.isClass();
130 } catch (final ClassNotFoundException e) {
131 return false;
132 }
133 }
134
135 /**
136 * Return true if this type references an interface, false if it references a class.
137 *
138 * @return true if the type references an interface, false if it references a class.
139 * @throws ClassNotFoundException if the class or interface referenced by this type can't be found
140 */
141 public boolean referencesInterfaceExact() throws ClassNotFoundException {
142 final JavaClass jc = Repository.lookupClass(className);
143 return !jc.isClass();
144 }
145
146 /**
147 * Return true if this type is a subclass of given ObjectType.
148 *
149 * @throws ClassNotFoundException if any of this class's superclasses can't be found
150 */
151 public boolean subclassOf(final ObjectType superclass) throws ClassNotFoundException {
152 if (referencesInterfaceExact() || superclass.referencesInterfaceExact()) {
153 return false;
154 }
155 return Repository.instanceOf(this.className, superclass.className);
156 }
157 }