View Javadoc
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.commons.compress.harmony.unpack200.bytecode;
20  
21  import java.io.DataOutputStream;
22  import java.io.IOException;
23  import java.util.Objects;
24  
25  /**
26   * Abstract superclass for reference constant pool entries, such as a method or field reference.
27   */
28  public abstract class CPRef extends ConstantPoolEntry {
29  
30      CPClass className;
31      transient int classNameIndex;
32  
33      protected CPNameAndType nameAndType;
34      transient int nameAndTypeIndex;
35  
36      protected String cachedToString;
37  
38      /**
39       * Constructs a new CPRef.
40       *
41       * @param type        TODO
42       * @param className   TODO
43       * @param descriptor  TODO
44       * @param globalIndex index in CpBands
45       * @throws NullPointerException if descriptor or className is null
46       */
47      public CPRef(final byte type, final CPClass className, final CPNameAndType descriptor, final int globalIndex) {
48          super(type, globalIndex);
49          this.className = Objects.requireNonNull(className, "className");
50          this.nameAndType = Objects.requireNonNull(descriptor, "descriptor");
51      }
52  
53      @Override
54      public boolean equals(final Object obj) {
55          if (this == obj) {
56              return true;
57          }
58          if (obj == null || getClass() != obj.getClass() || hashCode() != obj.hashCode()) {
59              return false;
60          }
61          final CPRef other = (CPRef) obj;
62          return Objects.equals(className, other.className)
63                  && Objects.equals(nameAndType, other.nameAndType);
64      }
65  
66      @Override
67      protected ClassFileEntry[] getNestedClassFileEntries() {
68          final ClassFileEntry[] entries = new ClassFileEntry[2];
69          entries[0] = className;
70          entries[1] = nameAndType;
71          return entries;
72      }
73  
74      @Override
75      protected void resolve(final ClassConstantPool pool) {
76          super.resolve(pool);
77          nameAndTypeIndex = pool.indexOf(nameAndType);
78          classNameIndex = pool.indexOf(className);
79      }
80  
81      @Override
82      public String toString() {
83          if (cachedToString == null) {
84              final String type;
85              if (getTag() == CP_Fieldref) {
86                  type = "FieldRef"; //$NON-NLS-1$
87              } else if (getTag() == CP_Methodref) {
88                  type = "MethoddRef"; //$NON-NLS-1$
89              } else if (getTag() == CP_InterfaceMethodref) {
90                  type = "InterfaceMethodRef"; //$NON-NLS-1$
91              } else {
92                  type = "unknown"; //$NON-NLS-1$
93              }
94              cachedToString = type + ": " + className + "#" + nameAndType; //$NON-NLS-1$ //$NON-NLS-2$
95          }
96          return cachedToString;
97      }
98  
99      @Override
100     protected void writeBody(final DataOutputStream dos) throws IOException {
101         dos.writeShort(classNameIndex);
102         dos.writeShort(nameAndTypeIndex);
103     }
104 
105 }