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1   /*
2    * Copyright  2000-2004 The Apache Software Foundation
3    *
4    *  Licensed under the Apache License, Version 2.0 (the "License"); 
5    *  you may not use this file except in compliance with the License.
6    *  You may obtain a copy of the License at
7    *
8    *      http://www.apache.org/licenses/LICENSE-2.0
9    *
10   *  Unless required by applicable law or agreed to in writing, software
11   *  distributed under the License is distributed on an "AS IS" BASIS,
12   *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13   *  See the License for the specific language governing permissions and
14   *  limitations under the License. 
15   *
16   */
17  package org.apache.bcel.generic;
18  
19  /***
20   * Denotes an unparameterized instruction to load a value from a local
21   * variable, e.g. ILOAD.
22   *
23   * @version $Id: LoadInstruction.java 386056 2006-03-15 11:31:56Z tcurdt $
24   * @author <A HREF="mailto:m.dahm@gmx.de">M. Dahm</A>
25   */
26  public abstract class LoadInstruction extends LocalVariableInstruction implements PushInstruction {
27  
28      /***
29       * Empty constructor needed for the Class.newInstance() statement in
30       * Instruction.readInstruction(). Not to be used otherwise.
31       * tag and length are defined in readInstruction and initFromFile, respectively.
32       */
33      LoadInstruction(short canon_tag, short c_tag) {
34          super(canon_tag, c_tag);
35      }
36  
37  
38      /***
39       * @param opcode Instruction opcode
40       * @param c_tag Instruction number for compact version, ALOAD_0, e.g.
41       * @param n local variable index (unsigned short)
42       */
43      protected LoadInstruction(short opcode, short c_tag, int n) {
44          super(opcode, c_tag, n);
45      }
46  
47  
48      /***
49       * Call corresponding visitor method(s). The order is:
50       * Call visitor methods of implemented interfaces first, then
51       * call methods according to the class hierarchy in descending order,
52       * i.e., the most specific visitXXX() call comes last.
53       *
54       * @param v Visitor object
55       */
56      public void accept( Visitor v ) {
57          v.visitStackProducer(this);
58          v.visitPushInstruction(this);
59          v.visitTypedInstruction(this);
60          v.visitLocalVariableInstruction(this);
61          v.visitLoadInstruction(this);
62      }
63  }