1 /*
2 * Copyright (c) 2017, 2019, Oracle and/or its affiliates. All rights reserved.
3 */
4 /*
5 * Licensed to the Apache Software Foundation (ASF) under one or more
6 * contributor license agreements. See the NOTICE file distributed with
7 * this work for additional information regarding copyright ownership.
8 * The ASF licenses this file to You under the Apache License, Version 2.0
9 * (the "License"); you may not use this file except in compliance with
10 * the License. You may obtain a copy of the License at
11 *
12 * http://www.apache.org/licenses/LICENSE-2.0
13 *
14 * Unless required by applicable law or agreed to in writing, software
15 * distributed under the License is distributed on an "AS IS" BASIS,
16 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
17 * See the License for the specific language governing permissions and
18 * limitations under the License.
19 */
20
21 package com.sun.org.apache.bcel.internal.generic;
22
23 import com.sun.org.apache.bcel.internal.Const;
24
25 /**
26 * Wrapper class for push operations, which are implemented either as BIPUSH,
27 * LDC or xCONST_n instructions.
28 *
29 * @version $Id$
30 * @LastModified: Jun 2019
31 */
32 public final class PUSH implements CompoundInstruction, VariableLengthInstruction {
33
34 private Instruction instruction;
35
36
37 /**
38 * This constructor also applies for values of type short, char, byte
39 *
40 * @param cp Constant pool
41 * @param value to be pushed
42 */
43 public PUSH(final ConstantPoolGen cp, final int value) {
44 if ((value >= -1) && (value <= 5)) {
45 instruction = InstructionConst.getInstruction(Const.ICONST_0 + value);
46 } else if (Instruction.isValidByte(value)) {
47 instruction = new BIPUSH((byte) value);
48 } else if (Instruction.isValidShort(value)) {
49 instruction = new SIPUSH((short) value);
50 } else {
51 instruction = new LDC(cp.addInteger(value));
52 }
53 }
54
55
56 /**
57 * @param cp Constant pool
58 * @param value to be pushed
59 */
60 public PUSH(final ConstantPoolGen cp, final boolean value) {
61 instruction = InstructionConst.getInstruction(Const.ICONST_0 + (value ? 1 : 0));
62 }
63
64
65 /**
66 * @param cp Constant pool
67 * @param value to be pushed
68 */
69 public PUSH(final ConstantPoolGen cp, final float value) {
70 if (value == 0.0) {
71 instruction = InstructionConst.FCONST_0;
72 } else if (value == 1.0) {
73 instruction = InstructionConst.FCONST_1;
74 } else if (value == 2.0) {
75 instruction = InstructionConst.FCONST_2;
76 } else {
77 instruction = new LDC(cp.addFloat(value));
78 }
79 }
80
81
82 /**
83 * @param cp Constant pool
84 * @param value to be pushed
85 */
86 public PUSH(final ConstantPoolGen cp, final long value) {
87 if (value == 0) {
88 instruction = InstructionConst.LCONST_0;
89 } else if (value == 1) {
90 instruction = InstructionConst.LCONST_1;
91 } else {
92 instruction = new LDC2_W(cp.addLong(value));
93 }
94 }
95
96
97 /**
98 * @param cp Constant pool
99 * @param value to be pushed
100 */
101 public PUSH(final ConstantPoolGen cp, final double value) {
102 if (value == 0.0) {
103 instruction = InstructionConst.DCONST_0;
104 } else if (value == 1.0) {
105 instruction = InstructionConst.DCONST_1;
106 } else {
107 instruction = new LDC2_W(cp.addDouble(value));
108 }
109 }
110
111
112 /**
113 * @param cp Constant pool
114 * @param value to be pushed
115 */
116 public PUSH(final ConstantPoolGen cp, final String value) {
117 if (value == null) {
118 instruction = InstructionConst.ACONST_NULL;
119 } else {
120 instruction = new LDC(cp.addString(value));
121 }
122 }
123
124 /**
125 *
126 * @param cp
127 * @param value
128 * @since 6.0
129 */
130 public PUSH(final ConstantPoolGen cp, final ObjectType value) {
131 if (value == null) {
132 instruction = InstructionConst.ACONST_NULL;
133 } else {
134 instruction = new LDC(cp.addClass(value));
135 }
136 }
137
138 /**
139 * @param cp Constant pool
140 * @param value to be pushed
141 */
142 public PUSH(final ConstantPoolGen cp, final Number value) {
143 if ((value instanceof Integer) || (value instanceof Short) || (value instanceof Byte)) {
144 instruction = new PUSH(cp, value.intValue()).instruction;
145 } else if (value instanceof Double) {
146 instruction = new PUSH(cp, value.doubleValue()).instruction;
147 } else if (value instanceof Float) {
148 instruction = new PUSH(cp, value.floatValue()).instruction;
149 } else if (value instanceof Long) {
150 instruction = new PUSH(cp, value.longValue()).instruction;
151 } else {
152 throw new ClassGenException("What's this: " + value);
153 }
154 }
155
156
157 /**
158 * creates a push object from a Character value. Warning: Make sure not to attempt to allow
159 * autoboxing to create this value parameter, as an alternative constructor will be called
160 *
161 * @param cp Constant pool
162 * @param value to be pushed
163 */
164 public PUSH(final ConstantPoolGen cp, final Character value) {
165 this(cp, value.charValue());
166 }
167
168
169 /**
170 * @param cp Constant pool
171 * @param value to be pushed
172 */
173 public PUSH(final ConstantPoolGen cp, final Boolean value) {
174 this(cp, value.booleanValue());
175 }
176
177
178 @Override
179 public final InstructionList getInstructionList() {
180 return new InstructionList(instruction);
181 }
182
183
184 public final Instruction getInstruction() {
185 return instruction;
186 }
187
188
189 /**
190 * @return mnemonic for instruction
191 */
192 @Override
193 public String toString() {
194 return instruction + " (PUSH)";
195 }
196 }