java.lang.Object
java.lang.Boolean
- All Implemented Interfaces:
Serializable
,Comparable<Boolean>
public final class Boolean extends Object implements Serializable, Comparable<Boolean>
The Boolean class wraps a value of the primitive type
boolean
in an object. 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
.
- Since:
- 1.0
- See Also:
- Serialized Form
-
Field Summary
-
Constructor Summary
-
Method Summary
Modifier and Type Method Description boolean
booleanValue()
Returns the value of thisBoolean
object as a boolean primitive.static int
compare(boolean x, boolean y)
Compares twoboolean
values.int
compareTo(Boolean b)
Compares thisBoolean
instance with another.boolean
equals(Object obj)
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
parseBoolean(String s)
Parses the string argument as a boolean.String
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
valueOf(String s)
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
The Class object representing the primitive type boolean.- Since:
- 1.1
-
-
Constructor Details
-
Boolean
Deprecated.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.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
Returns aString
object representing this Boolean's value. If this object represents the valuetrue
, a string equal to"true"
is returned. Otherwise, a string equal to"false"
is returned. -
hashCode
public int hashCode()Returns a hash code for thisBoolean
object.- Overrides:
hashCode
in classObject
- Returns:
- the integer
1231
if this object representstrue
; returns the integer1237
if this object representsfalse
. - See Also:
Object.equals(java.lang.Object)
,System.identityHashCode(java.lang.Object)
-
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.- Overrides:
equals
in classObject
- Parameters:
obj
- the object to compare with.- Returns:
true
if the Boolean objects represent the same value;false
otherwise.- See Also:
Object.hashCode()
,HashMap
-
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:
System.getProperty(java.lang.String)
,System.getProperty(java.lang.String, java.lang.String)
-
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:
Comparable
-
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:
BinaryOperator
-
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:
BinaryOperator
-
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:
BinaryOperator
-