Class Boolean
java.lang.Object
java.lang.Boolean
- All Implemented Interfaces:
Serializable
,Comparable<Boolean>
,Constable
The
Boolean
class is the wrapper class for values of the primitive
type boolean
. An object of type Boolean
contains a
single field whose type is boolean
.
In addition, this class provides many methods for
converting a boolean
to a String
and a
String
to a boolean
, as well as other
constants and methods useful when dealing with a
boolean
.
This is a value-based class; programmers should treat instances that are equal as interchangeable and should not use instances for synchronization, or unpredictable behavior may occur. For example, in a future release, synchronization may fail.
- Since:
- 1.0
- See Also:
-
Field Summary
-
Constructor Summary
ConstructorDescriptionBoolean
(boolean value) Deprecated, for removal: This API element is subject to removal in a future version.It is rarely appropriate to use this constructor.Deprecated, for removal: This API element is subject to removal in a future version.It is rarely appropriate to use this constructor. -
Method Summary
Modifier and TypeMethodDescriptionboolean
Returns the value of thisBoolean
object as a boolean primitive.static int
compare
(boolean x, boolean y) Compares twoboolean
values.int
Compares thisBoolean
instance with another.Returns anOptional
containing the nominal descriptor for this instance.boolean
Returnstrue
if and only if the argument is notnull
and is aBoolean
object that represents the sameboolean
value as this object.static boolean
getBoolean
(String name) Returnstrue
if and only if the system property named by the argument exists and is equal to, ignoring case, the string"true"
.int
hashCode()
Returns a hash code for thisBoolean
object.static int
hashCode
(boolean value) Returns a hash code for aboolean
value; compatible withBoolean.hashCode()
.static boolean
logicalAnd
(boolean a, boolean b) Returns the result of applying the logical AND operator to the specifiedboolean
operands.static boolean
logicalOr
(boolean a, boolean b) Returns the result of applying the logical OR operator to the specifiedboolean
operands.static boolean
logicalXor
(boolean a, boolean b) Returns the result of applying the logical XOR operator to the specifiedboolean
operands.static boolean
Parses the string argument as a boolean.toString()
Returns aString
object representing this Boolean's value.static String
toString
(boolean b) Returns aString
object representing the specified boolean.static Boolean
valueOf
(boolean b) Returns aBoolean
instance representing the specifiedboolean
value.static Boolean
Returns aBoolean
with a value represented by the specified string.
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Field Details
-
TRUE
TheBoolean
object corresponding to the primitive valuetrue
. -
FALSE
TheBoolean
object corresponding to the primitive valuefalse
. -
TYPE
-
-
Constructor Details
-
Boolean
Deprecated, for removal: This API element is subject to removal in a future version.It is rarely appropriate to use this constructor. The static factoryvalueOf(boolean)
is generally a better choice, as it is likely to yield significantly better space and time performance. Also consider using the final fieldsTRUE
andFALSE
if possible.Allocates aBoolean
object representing thevalue
argument.- Parameters:
value
- the value of theBoolean
.
-
Boolean
Deprecated, for removal: This API element is subject to removal in a future version.It is rarely appropriate to use this constructor. UseparseBoolean(String)
to convert a string to aboolean
primitive, or usevalueOf(String)
to convert a string to aBoolean
object.Allocates aBoolean
object representing the valuetrue
if the string argument is notnull
and is equal, ignoring case, to the string"true"
. Otherwise, allocates aBoolean
object representing the valuefalse
.- Parameters:
s
- the string to be converted to aBoolean
.
-
-
Method Details
-
parseBoolean
Parses the string argument as a boolean. Theboolean
returned represents the valuetrue
if the string argument is notnull
and is equal, ignoring case, to the string"true"
. Otherwise, a false value is returned, including for a null argument.Example:
Boolean.parseBoolean("True")
returnstrue
.
Example:Boolean.parseBoolean("yes")
returnsfalse
.- Parameters:
s
- theString
containing the boolean representation to be parsed- Returns:
- the boolean represented by the string argument
- Since:
- 1.5
-
booleanValue
public boolean booleanValue()Returns the value of thisBoolean
object as a boolean primitive.- Returns:
- the primitive
boolean
value of this object.
-
valueOf
Returns aBoolean
instance representing the specifiedboolean
value. If the specifiedboolean
value istrue
, this method returnsBoolean.TRUE
; if it isfalse
, this method returnsBoolean.FALSE
. If a newBoolean
instance is not required, this method should generally be used in preference to the constructorBoolean(boolean)
, as this method is likely to yield significantly better space and time performance.- Parameters:
b
- a boolean value.- Returns:
- a
Boolean
instance representingb
. - Since:
- 1.4
-
valueOf
Returns aBoolean
with a value represented by the specified string. TheBoolean
returned represents a true value if the string argument is notnull
and is equal, ignoring case, to the string"true"
. Otherwise, a false value is returned, including for a null argument.- Parameters:
s
- a string.- Returns:
- the
Boolean
value represented by the string.
-
toString
Returns aString
object representing the specified boolean. If the specified boolean istrue
, then the string"true"
will be returned, otherwise the string"false"
will be returned.- Parameters:
b
- the boolean to be converted- Returns:
- the string representation of the specified
boolean
- Since:
- 1.4
-
toString
-
hashCode
-
hashCode
public static int hashCode(boolean value) Returns a hash code for aboolean
value; compatible withBoolean.hashCode()
.- Parameters:
value
- the value to hash- Returns:
- a hash code value for a
boolean
value. - Since:
- 1.8
-
equals
Returnstrue
if and only if the argument is notnull
and is aBoolean
object that represents the sameboolean
value as this object. -
getBoolean
Returnstrue
if and only if the system property named by the argument exists and is equal to, ignoring case, the string"true"
. A system property is accessible throughgetProperty
, a method defined by theSystem
class.If there is no property with the specified name, or if the specified name is empty or null, then
false
is returned.- Parameters:
name
- the system property name.- Returns:
- the
boolean
value of the system property. - Throws:
SecurityException
- for the same reasons asSystem.getProperty
- See Also:
-
compareTo
Compares thisBoolean
instance with another.- Specified by:
compareTo
in interfaceComparable<Boolean>
- Parameters:
b
- theBoolean
instance to be compared- Returns:
- zero if this object represents the same boolean value as the argument; a positive value if this object represents true and the argument represents false; and a negative value if this object represents false and the argument represents true
- Throws:
NullPointerException
- if the argument isnull
- Since:
- 1.5
- See Also:
-
compare
public static int compare(boolean x, boolean y) Compares twoboolean
values. The value returned is identical to what would be returned by:Boolean.valueOf(x).compareTo(Boolean.valueOf(y))
- Parameters:
x
- the firstboolean
to comparey
- the secondboolean
to compare- Returns:
- the value
0
ifx == y
; a value less than0
if!x && y
; and a value greater than0
ifx && !y
- Since:
- 1.7
-
logicalAnd
public static boolean logicalAnd(boolean a, boolean b) Returns the result of applying the logical AND operator to the specifiedboolean
operands.- Parameters:
a
- the first operandb
- the second operand- Returns:
- the logical AND of
a
andb
- Since:
- 1.8
- See Also:
-
logicalOr
public static boolean logicalOr(boolean a, boolean b) Returns the result of applying the logical OR operator to the specifiedboolean
operands.- Parameters:
a
- the first operandb
- the second operand- Returns:
- the logical OR of
a
andb
- Since:
- 1.8
- See Also:
-
logicalXor
public static boolean logicalXor(boolean a, boolean b) Returns the result of applying the logical XOR operator to the specifiedboolean
operands.- Parameters:
a
- the first operandb
- the second operand- Returns:
- the logical XOR of
a
andb
- Since:
- 1.8
- See Also:
-
describeConstable
Returns anOptional
containing the nominal descriptor for this instance.- Specified by:
describeConstable
in interfaceConstable
- Returns:
- an
Optional
describing the Boolean instance - Since:
- 15
-