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.bcel.generic;
18
19 /**
20 * IFNULL - Branch if reference is not null
21 *
22 * <PRE>
23 * Stack: ..., reference -> ...
24 * </PRE>
25 */
26 public class IFNULL extends IfInstruction {
27
28 /**
29 * Empty constructor needed for Instruction.readInstruction. Not to be used otherwise.
30 */
31 IFNULL() {
32 }
33
34 public IFNULL(final InstructionHandle target) {
35 super(org.apache.bcel.Const.IFNULL, target);
36 }
37
38 /**
39 * Call corresponding visitor method(s). The order is: Call visitor methods of implemented interfaces first, then call
40 * methods according to the class hierarchy in descending order, i.e., the most specific visitXXX() call comes last.
41 *
42 * @param v Visitor object
43 */
44 @Override
45 public void accept(final Visitor v) {
46 v.visitStackConsumer(this);
47 v.visitBranchInstruction(this);
48 v.visitIfInstruction(this);
49 v.visitIFNULL(this);
50 }
51
52 /**
53 * @return negation of instruction
54 */
55 @Override
56 public IfInstruction negate() {
57 return new IFNONNULL(super.getTarget());
58 }
59 }