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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.SegmentConstantPool;
23  import org.apache.commons.compress.harmony.unpack200.bytecode.ByteCode;
24  import org.apache.commons.compress.harmony.unpack200.bytecode.ClassFileEntry;
25  import org.apache.commons.compress.harmony.unpack200.bytecode.OperandManager;
26  
27  /**
28   * This class implements the byte code form for those bytecodes which have string references (and only string references).
29   */
30  public class StringRefForm extends SingleByteReferenceForm {
31  
32      /**
33       * Constructs a new instance with the specified opcode, name, operandType and rewrite.
34       *
35       * @param opcode  index corresponding to the opcode's value.
36       * @param name    String printable name of the opcode.
37       * @param rewrite Operand positions (which will later be rewritten in ByteCodes) are indicated by -1.
38       */
39      public StringRefForm(final int opcode, final String name, final int[] rewrite) {
40          super(opcode, name, rewrite);
41      }
42  
43      /**
44       * Constructs a new instance with the specified opcode, name, operandType and rewrite.
45       *
46       * @param opcode  index corresponding to the opcode's value.
47       * @param name    String printable name of the opcode.
48       * @param rewrite Operand positions (which will later be rewritten in ByteCodes) are indicated by -1.
49       * @param widened TODO.
50       */
51      public StringRefForm(final int opcode, final String name, final int[] rewrite, final boolean widened) {
52          this(opcode, name, rewrite);
53          this.widened = widened;
54      }
55  
56      @Override
57      protected int getOffset(final OperandManager operandManager) {
58          return operandManager.nextStringRef();
59      }
60  
61      @Override
62      protected int getPoolID() {
63          return SegmentConstantPool.CP_STRING;
64      }
65  
66      @Override
67      protected void setNestedEntries(final ByteCode byteCode, final OperandManager operandManager, final int offset) throws Pack200Exception {
68          final SegmentConstantPool globalPool = operandManager.globalConstantPool();
69          final ClassFileEntry[] nested = { globalPool.getValue(getPoolID(), offset) };
70          byteCode.setNested(nested);
71          if (widened) {
72              byteCode.setNestedPositions(new int[][] { { 0, 2 } });
73          } else {
74              byteCode.setNestedPositions(new int[][] { { 0, 1 } });
75          }
76      }
77  }