java.io.Serializable
, Comparable<Boolean>
public final class Boolean extends Object implements java.io.Serializable, Comparable<Boolean>
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
.
Modifier and Type | Field | Description |
---|---|---|
static Boolean |
FALSE |
The
Boolean object corresponding to the primitive
value false . |
static Boolean |
TRUE |
The
Boolean object corresponding to the primitive
value true . |
static Class<Boolean> |
TYPE |
The Class object representing the primitive type boolean.
|
Constructor | Description |
---|---|
Boolean(boolean value) |
Deprecated.
It is rarely appropriate to use this constructor.
|
Boolean(String s) |
Deprecated.
It is rarely appropriate to use this constructor.
|
Modifier and Type | Method | Description |
---|---|---|
boolean |
booleanValue() |
Returns the value of this
Boolean object as a boolean
primitive. |
static int |
compare(boolean x,
boolean y) |
Compares two
boolean values. |
int |
compareTo(Boolean b) |
Compares this
Boolean instance with another. |
boolean |
equals(Object obj) |
Returns
true if and only if the argument is not
null and is a Boolean object that
represents the same boolean value as this object. |
static boolean |
getBoolean(String name) |
Returns
true 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 this
Boolean object. |
static int |
hashCode(boolean value) |
Returns a hash code for a
boolean value; compatible with
Boolean.hashCode() . |
static boolean |
logicalAnd(boolean a,
boolean b) |
Returns the result of applying the logical AND operator to the
specified
boolean operands. |
static boolean |
logicalOr(boolean a,
boolean b) |
Returns the result of applying the logical OR operator to the
specified
boolean operands. |
static boolean |
logicalXor(boolean a,
boolean b) |
Returns the result of applying the logical XOR operator to the
specified
boolean operands. |
static boolean |
parseBoolean(String s) |
Parses the string argument as a boolean.
|
String |
toString() |
Returns a
String object representing this Boolean's
value. |
static String |
toString(boolean b) |
Returns a
String object representing the specified
boolean. |
static Boolean |
valueOf(boolean b) |
Returns a
Boolean instance representing the specified
boolean value. |
static Boolean |
valueOf(String s) |
Returns a
Boolean with a value represented by the
specified string. |
public static final Boolean TRUE
Boolean
object corresponding to the primitive
value true
.public static final Boolean FALSE
Boolean
object corresponding to the primitive
value false
.@Deprecated(since="9") public Boolean(boolean value)
valueOf(boolean)
is generally a better choice, as it is
likely to yield significantly better space and time performance.
Also consider using the final fields TRUE
and FALSE
if possible.Boolean
object representing the
value
argument.value
- the value of the Boolean
.@Deprecated(since="9") public Boolean(String s)
parseBoolean(String)
to convert a string to a
boolean
primitive, or use valueOf(String)
to convert a string to a Boolean
object.Boolean
object representing the value
true
if the string argument is not null
and is equal, ignoring case, to the string "true"
.
Otherwise, allocates a Boolean
object representing the
value false
.s
- the string to be converted to a Boolean
.public static boolean parseBoolean(String s)
boolean
returned represents the value true
if the string argument
is not null
and is equal, ignoring case, to the string
"true"
.
Otherwise, a false value is returned, including for a null
argument.
Example: Boolean.parseBoolean("True")
returns true
.
Example: Boolean.parseBoolean("yes")
returns false
.
s
- the String
containing the boolean
representation to be parsedpublic boolean booleanValue()
Boolean
object as a boolean
primitive.boolean
value of this object.public static Boolean valueOf(boolean b)
Boolean
instance representing the specified
boolean
value. If the specified boolean
value
is true
, this method returns Boolean.TRUE
;
if it is false
, this method returns Boolean.FALSE
.
If a new Boolean
instance is not required, this method
should generally be used in preference to the constructor
Boolean(boolean)
, as this method is likely to yield
significantly better space and time performance.b
- a boolean value.Boolean
instance representing b
.public static Boolean valueOf(String s)
Boolean
with a value represented by the
specified string. The Boolean
returned represents a
true value if the string argument is not null
and is equal, ignoring case, to the string "true"
.
Otherwise, a false value is returned, including for a null
argument.s
- a string.Boolean
value represented by the string.public static String toString(boolean b)
String
object representing the specified
boolean. If the specified boolean is true
, then
the string "true"
will be returned, otherwise the
string "false"
will be returned.b
- the boolean to be convertedboolean
public String toString()
String
object representing this Boolean's
value. If this object represents the value true
,
a string equal to "true"
is returned. Otherwise, a
string equal to "false"
is returned.public int hashCode()
Boolean
object.hashCode
in class Object
1231
if this object represents
true
; returns the integer 1237
if this
object represents false
.Object.equals(java.lang.Object)
,
System.identityHashCode(java.lang.Object)
public static int hashCode(boolean value)
boolean
value; compatible with
Boolean.hashCode()
.value
- the value to hashboolean
value.public boolean equals(Object obj)
true
if and only if the argument is not
null
and is a Boolean
object that
represents the same boolean
value as this object.equals
in class Object
obj
- the object to compare with.true
if the Boolean objects represent the
same value; false
otherwise.Object.hashCode()
,
HashMap
public static boolean getBoolean(String name)
true
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 through getProperty
, a
method defined by the System
class. If there is no
property with the specified name, or if the specified name is
empty or null, then false
is returned.
name
- the system property name.boolean
value of the system property.SecurityException
- for the same reasons as
System.getProperty
System.getProperty(java.lang.String)
,
System.getProperty(java.lang.String, java.lang.String)
public int compareTo(Boolean b)
Boolean
instance with another.compareTo
in interface Comparable<Boolean>
b
- the Boolean
instance to be comparedNullPointerException
- if the argument is null
Comparable
public static int compare(boolean x, boolean y)
boolean
values.
The value returned is identical to what would be returned by:
Boolean.valueOf(x).compareTo(Boolean.valueOf(y))
x
- the first boolean
to comparey
- the second boolean
to compare0
if x == y
;
a value less than 0
if !x && y
; and
a value greater than 0
if x && !y
public static boolean logicalAnd(boolean a, boolean b)
boolean
operands.a
- the first operandb
- the second operanda
and b
BinaryOperator
public static boolean logicalOr(boolean a, boolean b)
boolean
operands.a
- the first operandb
- the second operanda
and b
BinaryOperator
public static boolean logicalXor(boolean a, boolean b)
boolean
operands.a
- the first operandb
- the second operanda
and b
BinaryOperator