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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.commons.compress.harmony.unpack200.bytecode.forms;
20  
21  import org.apache.commons.compress.harmony.pack200.Pack200Exception;
22  import org.apache.commons.compress.harmony.unpack200.bytecode.ByteCode;
23  import org.apache.commons.compress.harmony.unpack200.bytecode.OperandManager;
24  
25  /**
26   * This class is used for representations of cldc and cldc_w. In these cases, a narrow class ref has one byte and a wide class ref has two bytes.
27   */
28  public class NarrowClassRefForm extends ClassRefForm {
29  
30      /**
31       * Constructs a new instance with the specified opcode, name, operandType and rewrite.
32       *
33       * @param opcode  index corresponding to the opcode's value.
34       * @param name    String printable name of the opcode.
35       * @param rewrite Operand positions (which will later be rewritten in ByteCodes) are indicated by -1.
36       */
37      public NarrowClassRefForm(final int opcode, final String name, final int[] rewrite) {
38          super(opcode, name, rewrite);
39      }
40  
41      /**
42       * Constructs a new instance with the specified opcode, name, operandType and rewrite.
43       *
44       * @param opcode  index corresponding to the opcode's value.
45       * @param name    String printable name of the opcode.
46       * @param rewrite Operand positions (which will later be rewritten in ByteCodes) are indicated by -1.
47       * @param widened TODO.
48       */
49      public NarrowClassRefForm(final int opcode, final String name, final int[] rewrite, final boolean widened) {
50          super(opcode, name, rewrite, widened);
51      }
52  
53      @Override
54      public boolean nestedMustStartClassPool() {
55          return !widened;
56      }
57  
58      @Override
59      protected void setNestedEntries(final ByteCode byteCode, final OperandManager operandManager, final int offset) throws Pack200Exception {
60          super.setNestedEntries(byteCode, operandManager, offset);
61          if (!widened) {
62              byteCode.setNestedPositions(new int[][] { { 0, 1 } });
63          }
64      }
65  }