View Javadoc
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  package org.apache.commons.compress.harmony.unpack200.bytecode.forms;
18  
19  import org.apache.commons.compress.harmony.pack200.Pack200Exception;
20  import org.apache.commons.compress.harmony.unpack200.SegmentConstantPool;
21  import org.apache.commons.compress.harmony.unpack200.bytecode.ByteCode;
22  import org.apache.commons.compress.harmony.unpack200.bytecode.CPClass;
23  import org.apache.commons.compress.harmony.unpack200.bytecode.ClassFileEntry;
24  import org.apache.commons.compress.harmony.unpack200.bytecode.OperandManager;
25  
26  /**
27   * This class is an extension of the ClassRefForm. It has two purposes: 1. To keep track of the last type used in a new() instruction in the current class. 2.
28   * To allow the sender to create instances of either a specified class (which then becomes the new class) or the last used new class.
29   */
30  public class NewClassRefForm extends ClassRefForm {
31  
32      public NewClassRefForm(final int opcode, final String name, final int[] rewrite) {
33          super(opcode, name, rewrite);
34      }
35  
36      /*
37       * (non-Javadoc)
38       *
39       * @see org.apache.commons.compress.harmony.unpack200.bytecode.forms.ReferenceForm#setByteCodeOperands(org.apache.commons
40       * .compress.harmony.unpack200.bytecode.ByteCode, org.apache.commons.compress.harmony.unpack200.bytecode.OperandManager)
41       */
42      @Override
43      public void setByteCodeOperands(final ByteCode byteCode, final OperandManager operandManager, final int codeLength) {
44          final int offset = getOffset(operandManager);
45          if (offset == 0) {
46              // Use current class
47              final SegmentConstantPool globalPool = operandManager.globalConstantPool();
48              final ClassFileEntry[] nested = { globalPool.getClassPoolEntry(operandManager.getCurrentClass()) };
49              byteCode.setNested(nested);
50              byteCode.setNestedPositions(new int[][] { { 0, 2 } });
51          } else {
52              // Look up the class in the classpool
53              try {
54                  // Parent takes care of subtracting one from offset
55                  // to adjust for 1-based global pool
56                  setNestedEntries(byteCode, operandManager, offset);
57              } catch (final Pack200Exception ex) {
58                  throw new Error("Got a pack200 exception. What to do?");
59              }
60          }
61          operandManager.setNewClass(((CPClass) byteCode.getNestedClassFileEntries()[0]).getName());
62      }
63  }