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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  
23  /**
24   * Denotes array type, such as int[][]
25   */
26  public final class ArrayType extends ReferenceType {
27  
28      private final int dimensions;
29      private final Type basicType;
30  
31      /**
32       * Convenience constructor for array type, for example int[]
33       *
34       * @param type array type, for example T_INT.
35       * @param dimensions array dimensions.
36       */
37      public ArrayType(final byte type, final int dimensions) {
38          this(BasicType.getType(type), dimensions);
39      }
40  
41      /**
42       * Convenience constructor for reference array type, for example Object[]
43       *
44       * @param className complete name of class ({@link String}, for example).
45       * @param dimensions array dimensions.
46       */
47      public ArrayType(final String className, final int dimensions) {
48          this(ObjectType.getInstance(className), dimensions);
49      }
50  
51      /**
52       * Constructor for array of given type
53       *
54       * @param type type of array (may be an array itself).
55       * @param dimensions array dimensions.
56       */
57      public ArrayType(final Type type, final int dimensions) {
58          super(Const.T_ARRAY, "<dummy>");
59          if (dimensions < 1 || dimensions > Const.MAX_BYTE) {
60              throw new ClassGenException("Invalid number of dimensions: " + dimensions);
61          }
62          switch (type.getType()) {
63          case Const.T_ARRAY:
64              final ArrayType array = (ArrayType) type;
65              this.dimensions = dimensions + array.dimensions;
66              basicType = array.basicType;
67              break;
68          case Const.T_VOID:
69              throw new ClassGenException("Invalid type: void[]");
70          default: // Basic type or reference
71              this.dimensions = dimensions;
72              basicType = type;
73              break;
74          }
75          final StringBuilder buf = new StringBuilder();
76          for (int i = 0; i < this.dimensions; i++) {
77              buf.append('[');
78          }
79          buf.append(basicType.getSignature());
80          this.signature = buf.toString();
81      }
82  
83      /**
84       * @return true if both type objects refer to the same array type.
85       */
86      @Override
87      public boolean equals(final Object type) {
88          if (type instanceof ArrayType) {
89              final ArrayType array = (ArrayType) type;
90              return array.dimensions == dimensions && array.basicType.equals(basicType);
91          }
92          return false;
93      }
94  
95      /**
96       * Gets the basic type of array, that is, for int[][][] the basic type is int.
97       *
98       * @return basic type of array, that is, for int[][][] the basic type is int.
99       */
100     public Type getBasicType() {
101         return basicType;
102     }
103 
104     /**
105      * Gets the name of referenced class.
106      *
107      * @return name of referenced class.
108      * @since 6.7.0
109      */
110     @Override
111     public String getClassName() {
112         return signature;
113     }
114 
115     /**
116      * Gets the number of dimensions of array.
117      *
118      * @return number of dimensions of array.
119      */
120     public int getDimensions() {
121         return dimensions;
122     }
123 
124     /**
125      * Gets the element type of array, that is, for int[][][] the element type is int[][].
126      *
127      * @return element type of array, that is, for int[][][] the element type is int[][].
128      */
129     public Type getElementType() {
130         if (dimensions == 1) {
131             return basicType;
132         }
133         return new ArrayType(basicType, dimensions - 1);
134     }
135 
136     /**
137      * @return a hash code value for the object.
138      */
139     @Override
140     public int hashCode() {
141         return basicType.hashCode() ^ dimensions;
142     }
143 }