1 /*
2 * Copyright (c) 1994, 2025, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package java.lang;
27
28 import jdk.internal.vm.annotation.IntrinsicCandidate;
29
30 import java.lang.constant.Constable;
31 import java.lang.constant.ConstantDescs;
32 import java.lang.constant.DynamicConstantDesc;
33 import java.util.Optional;
34
35 /**
36 * The {@code Boolean} class is the {@linkplain
37 * java.lang##wrapperClass wrapper class} for values of the primitive
38 * type {@code boolean}. An object of type {@code Boolean} contains a
39 * single field whose type is {@code boolean}.
40 *
41 * <p>In addition, this class provides many methods for
42 * converting a {@code boolean} to a {@code String} and a
43 * {@code String} to a {@code boolean}, as well as other
44 * constants and methods useful when dealing with a
45 * {@code boolean}.
46 *
47 * <p>This is a <a href="{@docRoot}/java.base/java/lang/doc-files/ValueBased.html">value-based</a>
48 * class; programmers should treat instances that are
49 * {@linkplain #equals(Object) equal} as interchangeable and should not
50 * use instances for synchronization, or unpredictable behavior may
51 * occur. For example, in a future release, synchronization may fail.
52 *
53 * @author Arthur van Hoff
54 * @since 1.0
55 */
56 @jdk.internal.ValueBased
57 public final class Boolean implements java.io.Serializable,
58 Comparable<Boolean>, Constable
59 {
60 /**
61 * The {@code Boolean} object corresponding to the primitive
62 * value {@code true}.
63 */
64 public static final Boolean TRUE = new Boolean(true);
65
66 /**
67 * The {@code Boolean} object corresponding to the primitive
68 * value {@code false}.
69 */
70 public static final Boolean FALSE = new Boolean(false);
71
72 /**
73 * The Class object representing the primitive type boolean.
74 *
75 * @since 1.1
76 */
77 public static final Class<Boolean> TYPE = Class.getPrimitiveClass("boolean");
78
84 private final boolean value;
85
86 /** use serialVersionUID from JDK 1.0.2 for interoperability */
87 @java.io.Serial
88 private static final long serialVersionUID = -3665804199014368530L;
89
90 /**
91 * Allocates a {@code Boolean} object representing the
92 * {@code value} argument.
93 *
94 * @param value the value of the {@code Boolean}.
95 *
96 * @deprecated
97 * It is rarely appropriate to use this constructor. The static factory
98 * {@link #valueOf(boolean)} is generally a better choice, as it is
99 * likely to yield significantly better space and time performance.
100 * Also consider using the final fields {@link #TRUE} and {@link #FALSE}
101 * if possible.
102 */
103 @Deprecated(since="9")
104 public Boolean(boolean value) {
105 this.value = value;
106 }
107
108 /**
109 * Allocates a {@code Boolean} object representing the value
110 * {@code true} if the string argument is not {@code null}
111 * and is equal, ignoring case, to the string {@code "true"}.
112 * Otherwise, allocates a {@code Boolean} object representing the
113 * value {@code false}.
114 *
115 * @param s the string to be converted to a {@code Boolean}.
116 *
117 * @deprecated
118 * It is rarely appropriate to use this constructor.
119 * Use {@link #parseBoolean(String)} to convert a string to a
120 * {@code boolean} primitive, or use {@link #valueOf(String)}
121 * to convert a string to a {@code Boolean} object.
122 */
123 @Deprecated(since="9")
140 * @return the boolean represented by the string argument
141 * @since 1.5
142 */
143 public static boolean parseBoolean(String s) {
144 return "true".equalsIgnoreCase(s);
145 }
146
147 /**
148 * Returns the value of this {@code Boolean} object as a boolean
149 * primitive.
150 *
151 * @return the primitive {@code boolean} value of this object.
152 */
153 @IntrinsicCandidate
154 public boolean booleanValue() {
155 return value;
156 }
157
158 /**
159 * Returns a {@code Boolean} instance representing the specified
160 * {@code boolean} value. If the specified {@code boolean} value
161 * is {@code true}, this method returns {@code Boolean.TRUE};
162 * if it is {@code false}, this method returns {@code Boolean.FALSE}.
163 * If a new {@code Boolean} instance is not required, this method
164 * should generally be used in preference to the constructor
165 * {@link #Boolean(boolean)}, as this method is likely to yield
166 * significantly better space and time performance.
167 *
168 * @param b a boolean value.
169 * @return a {@code Boolean} instance representing {@code b}.
170 * @since 1.4
171 */
172 @IntrinsicCandidate
173 public static Boolean valueOf(boolean b) {
174 return (b ? TRUE : FALSE);
175 }
176
177 /**
178 * Returns a {@code Boolean} with a value represented by the
179 * specified string. The {@code Boolean} returned represents a
180 * true value if the string argument is not {@code null}
181 * and is equal, ignoring case, to the string {@code "true"}.
182 * Otherwise, a false value is returned, including for a null
183 * argument.
184 *
185 * @param s a string.
186 * @return the {@code Boolean} value represented by the string.
|
1 /*
2 * Copyright (c) 1994, 2026, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package java.lang;
27
28 import jdk.internal.value.Deserializer;
29 import jdk.internal.vm.annotation.IntrinsicCandidate;
30
31 import java.lang.constant.Constable;
32 import java.lang.constant.ConstantDescs;
33 import java.lang.constant.DynamicConstantDesc;
34 import java.util.Optional;
35
36 /**
37 * The {@code Boolean} class is the {@linkplain
38 * java.lang##wrapperClass wrapper class} for values of the primitive
39 * type {@code boolean}. An object of type {@code Boolean} contains a
40 * single field whose type is {@code boolean}.
41 *
42 * <p>In addition, this class provides many methods for
43 * converting a {@code boolean} to a {@code String} and a
44 * {@code String} to a {@code boolean}, as well as other
45 * constants and methods useful when dealing with a
46 * {@code boolean}.
47 *
48 * <p>This is a <a href="{@docRoot}/java.base/java/lang/doc-files/ValueBased.html">value-based</a>
49 * class; programmers should treat instances that are {@linkplain #equals(Object) equal}
50 * as interchangeable and should not use instances for synchronization, mutexes, or
51 * with {@linkplain java.lang.ref.Reference object references}.
52 *
53 * <div class="preview-block">
54 * <div class="preview-comment">
55 * When preview features are enabled, {@code Boolean} is a {@linkplain Class#isValue value class}.
56 * Use of value class instances for synchronization, mutexes, or with
57 * {@linkplain java.lang.ref.Reference object references} result in
58 * {@link IdentityException}.
59 * </div>
60 * </div>
61 *
62 * @author Arthur van Hoff
63 * @since 1.0
64 */
65 @jdk.internal.MigratedValueClass
66 @jdk.internal.ValueBased
67 public final /*value*/ class Boolean
68 implements java.io.Serializable, Comparable<Boolean>, Constable
69 {
70 /**
71 * The {@code Boolean} object corresponding to the primitive
72 * value {@code true}.
73 */
74 public static final Boolean TRUE = new Boolean(true);
75
76 /**
77 * The {@code Boolean} object corresponding to the primitive
78 * value {@code false}.
79 */
80 public static final Boolean FALSE = new Boolean(false);
81
82 /**
83 * The Class object representing the primitive type boolean.
84 *
85 * @since 1.1
86 */
87 public static final Class<Boolean> TYPE = Class.getPrimitiveClass("boolean");
88
94 private final boolean value;
95
96 /** use serialVersionUID from JDK 1.0.2 for interoperability */
97 @java.io.Serial
98 private static final long serialVersionUID = -3665804199014368530L;
99
100 /**
101 * Allocates a {@code Boolean} object representing the
102 * {@code value} argument.
103 *
104 * @param value the value of the {@code Boolean}.
105 *
106 * @deprecated
107 * It is rarely appropriate to use this constructor. The static factory
108 * {@link #valueOf(boolean)} is generally a better choice, as it is
109 * likely to yield significantly better space and time performance.
110 * Also consider using the final fields {@link #TRUE} and {@link #FALSE}
111 * if possible.
112 */
113 @Deprecated(since="9")
114 @Deserializer("value")
115 public Boolean(boolean value) {
116 this.value = value;
117 }
118
119 /**
120 * Allocates a {@code Boolean} object representing the value
121 * {@code true} if the string argument is not {@code null}
122 * and is equal, ignoring case, to the string {@code "true"}.
123 * Otherwise, allocates a {@code Boolean} object representing the
124 * value {@code false}.
125 *
126 * @param s the string to be converted to a {@code Boolean}.
127 *
128 * @deprecated
129 * It is rarely appropriate to use this constructor.
130 * Use {@link #parseBoolean(String)} to convert a string to a
131 * {@code boolean} primitive, or use {@link #valueOf(String)}
132 * to convert a string to a {@code Boolean} object.
133 */
134 @Deprecated(since="9")
151 * @return the boolean represented by the string argument
152 * @since 1.5
153 */
154 public static boolean parseBoolean(String s) {
155 return "true".equalsIgnoreCase(s);
156 }
157
158 /**
159 * Returns the value of this {@code Boolean} object as a boolean
160 * primitive.
161 *
162 * @return the primitive {@code boolean} value of this object.
163 */
164 @IntrinsicCandidate
165 public boolean booleanValue() {
166 return value;
167 }
168
169 /**
170 * Returns a {@code Boolean} instance representing the specified
171 * {@code boolean} value.
172 * <div class="preview-block">
173 * <div class="preview-comment">
174 * <p>
175 * - When preview features are NOT enabled, {@code Boolean} is an identity class.
176 * If the specified {@code boolean} value is {@code true},
177 * this method returns {@code Boolean.TRUE}; if it is
178 * {@code false}, this method returns {@code Boolean.FALSE}.
179 * If a new {@code Boolean} instance is not required, this
180 * method should generally be used in preference to the
181 * constructor {@link #Boolean(boolean)}, as this method is
182 * likely to yield significantly better space and time
183 * performance.
184 * </p>
185 * <p>
186 * - When preview features are enabled, {@code Boolean} is a {@linkplain Class#isValue value class}.
187 * The {@code valueOf} behavior is the same as invoking the constructor.
188 * </p>
189 * </div>
190 * </div>
191 *
192 * @param b a boolean value.
193 * @return a {@code Boolean} instance representing {@code b}.
194 * @since 1.4
195 */
196 @IntrinsicCandidate
197 public static Boolean valueOf(boolean b) {
198 return (b ? TRUE : FALSE);
199 }
200
201 /**
202 * Returns a {@code Boolean} with a value represented by the
203 * specified string. The {@code Boolean} returned represents a
204 * true value if the string argument is not {@code null}
205 * and is equal, ignoring case, to the string {@code "true"}.
206 * Otherwise, a false value is returned, including for a null
207 * argument.
208 *
209 * @param s a string.
210 * @return the {@code Boolean} value represented by the string.
|