java.lang
public final class Boolean extends Object implements Serializable
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: JDK1.0
Version: 1.45, 06/22/03
Field Summary | |
---|---|
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 Summary | |
---|---|
Boolean(boolean value)
Allocates a Boolean object representing the
value argument.
| |
Boolean(String s)
Allocates a Boolean object representing the value
true if the string argument is not null
and is equal, ignoring case, to the string "true" .
|
Method Summary | |
---|---|
boolean | booleanValue()
Returns the value of this Boolean object as a boolean
primitive.
|
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 the string
"true" . |
int | hashCode()
Returns a hash code for this Boolean object.
|
static boolean | parseBoolean(String s)
Parses the string argument as a boolean. |
static String | toString(boolean b)
Returns a String object representing the specified
boolean. |
String | toString()
Returns a String object representing this Boolean's
value. |
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. |
Boolean
object corresponding to the primitive
value false
.Boolean
object corresponding to the primitive
value true
.Since: JDK1.1
Boolean
object representing the
value
argument.
Note: It is rarely appropriate to use this constructor. Unless a new instance is required, the static factory Boolean is generally a better choice. It is likely to yield significantly better space and time performance.
Parameters: value the value of the Boolean
.
Boolean
object representing the value
true
if the string argument is not null
and is equal, ignoring case, to the string "true"
.
Otherwise, allocate a Boolean
object representing the
value false
. Examples:
new Boolean("True") produces a Boolean object
that represents true.
new Boolean("yes") produces a Boolean object
that represents false.
Parameters: s the string to be converted to a Boolean
.
Returns: the primitive boolean
value of this object.
true
if and only if the argument is not
null
and is a Boolean
object that
represents the same boolean
value as this object.
Parameters: obj the object to compare with.
Returns: true
if the Boolean objects represent the
same value; false
otherwise.
true
if and only if the system property
named by the argument exists and is equal to the string
"true"
. (Beginning with version 1.0.2 of the
JavaTM platform, the test of
this string is case insensitive.) 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.
Parameters: name the system property name.
Returns: the boolean
value of the system property.
See Also: java.lang.System#getProperty(java.lang.String) java.lang.System#getProperty(java.lang.String, java.lang.String)
Returns: the integer 1231 if this object represents true; returns the integer 1237 if this object represents false.
boolean
returned represents the value true
if the string argument
is not null
and is equal, ignoring case, to the string
"true"
.
Parameters: s the String
containing the boolean
representation to be parsed
Returns: the boolean represented by the string argument
Since: 1.5
true
, 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
true
,
a string equal to "true"
is returned. Otherwise, a
string equal to "false"
is returned.
Returns: a string representation of this object.
Parameters: b a boolean value.
Returns: a Boolean instance representing b.
Since: 1.4
Boolean
with a value represented by the
specified String. The Boolean
returned represents the
value true
if the string argument is not null
and is equal, ignoring case, to the string "true"
.
Example: Boolean.valueOf("True") returns true.
Example: Boolean.valueOf("yes") returns false.
Parameters: s a string.
Returns: the Boolean
value represented by the string.