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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one or more
3    * contributor license agreements.  See the NOTICE file distributed with
4    * this work for additional information regarding copyright ownership.
5    * The ASF licenses this file to You under the Apache License, Version 2.0
6    * (the "License"); you may not use this file except in compliance with
7    * the License.  You may obtain a copy of the License at
8    *
9    *      http://www.apache.org/licenses/LICENSE-2.0
10   *
11   *  Unless required by applicable law or agreed to in writing, software
12   *  distributed under the License is distributed on an "AS IS" BASIS,
13   *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14   *  See the License for the specific language governing permissions and
15   *  limitations under the License.
16   *
17   */
18  package org.apache.bcel.generic;
19  
20  import org.apache.bcel.Const;
21  
22  /**
23   * Denotes array type, such as int[][]
24   *
25   * @version $Id: ArrayType.html 1018313 2017-09-18 09:03:04Z britter $
26   */
27  public final class ArrayType extends ReferenceType {
28  
29      private int dimensions;
30      private Type basic_type;
31  
32  
33      /**
34       * Convenience constructor for array type, e.g. int[]
35       *
36       * @param type array type, e.g. T_INT
37       */
38      public ArrayType(final byte type, final int dimensions) {
39          this(BasicType.getType(type), dimensions);
40      }
41  
42  
43      /**
44       * Convenience constructor for reference array type, e.g. Object[]
45       *
46       * @param class_name complete name of class (java.lang.String, e.g.)
47       */
48      public ArrayType(final String class_name, final int dimensions) {
49          this(ObjectType.getInstance(class_name), dimensions);
50      }
51  
52  
53      /**
54       * Constructor for array of given type
55       *
56       * @param type type of array (may be an array itself)
57       */
58      public ArrayType(final Type type, final int dimensions) {
59          super(Const.T_ARRAY, "<dummy>");
60          if ((dimensions < 1) || (dimensions > Const.MAX_BYTE)) {
61              throw new ClassGenException("Invalid number of dimensions: " + dimensions);
62          }
63          switch (type.getType()) {
64              case Const.T_ARRAY:
65                  final ArrayType array = (ArrayType) type;
66                  this.dimensions = dimensions + array.dimensions;
67                  basic_type = array.basic_type;
68                  break;
69              case Const.T_VOID:
70                  throw new ClassGenException("Invalid type: void[]");
71              default: // Basic type or reference
72                  this.dimensions = dimensions;
73                  basic_type = type;
74                  break;
75          }
76          final StringBuilder buf = new StringBuilder();
77          for (int i = 0; i < this.dimensions; i++) {
78              buf.append('[');
79          }
80          buf.append(basic_type.getSignature());
81          super.setSignature(buf.toString());
82      }
83  
84  
85      /**
86       * @return basic type of array, i.e., for int[][][] the basic type is int
87       */
88      public Type getBasicType() {
89          return basic_type;
90      }
91  
92  
93      /**
94       * @return element type of array, i.e., for int[][][] the element type is int[][]
95       */
96      public Type getElementType() {
97          if (dimensions == 1) {
98              return basic_type;
99          }
100         return new ArrayType(basic_type, dimensions - 1);
101     }
102 
103 
104     /** @return number of dimensions of array
105      */
106     public int getDimensions() {
107         return dimensions;
108     }
109 
110 
111     /** @return a hash code value for the object.
112      */
113     @Override
114     public int hashCode() {
115         return basic_type.hashCode() ^ dimensions;
116     }
117 
118 
119     /** @return true if both type objects refer to the same array type.
120      */
121     @Override
122     public boolean equals( final Object _type ) {
123         if (_type instanceof ArrayType) {
124             final ArrayType array = (ArrayType) _type;
125             return (array.dimensions == dimensions) && array.basic_type.equals(basic_type);
126         }
127         return false;
128     }
129 }