Added in API level 1

Boolean

class Boolean : Serializable, Comparable<Boolean!>

kotlin.Any
↳	java.lang.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.

Summary

Public constructors
Boolean(value: Boolean) Allocates a Boolean object representing the value argument.
Boolean(s: String?) Allocates a Boolean object representing the value true if the string argument is not null and is equal, ignoring case, to the string "true".

Public methods
Boolean	booleanValue() Returns the value of this Boolean object as a boolean primitive.
static Int	compare(x: Boolean, y: Boolean) Compares two boolean values.
Int	compareTo(other: Boolean) Compares this Boolean instance with another.
Boolean	equals(other: Any?) 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(name: String) 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(value: Boolean) Returns a hash code for a boolean value; compatible with Boolean.hashCode().
static Boolean	logicalAnd(a: Boolean, b: Boolean) Returns the result of applying the logical AND operator to the specified boolean operands.
static Boolean	logicalOr(a: Boolean, b: Boolean) Returns the result of applying the logical OR operator to the specified boolean operands.
static Boolean	logicalXor(a: Boolean, b: Boolean) Returns the result of applying the logical XOR operator to the specified boolean operands.
static Boolean	parseBoolean(s: String?) Parses the string argument as a boolean.
String	toString() Returns a String object representing this Boolean's value.
static String	toString(b: Boolean) Returns a String object representing the specified boolean.
static Boolean	valueOf(b: Boolean) Returns a Boolean instance representing the specified boolean value.
static Boolean	valueOf(s: String?) Returns a Boolean with a value represented by the specified string.

Properties
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.

Public constructors

Boolean

Added in API level 1

Boolean(value: Boolean)

Deprecated: It is rarely appropriate to use this constructor. The static factory 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.

Allocates a Boolean object representing the value argument.

Parameters
value	Boolean: the value of the Boolean.

Boolean

Added in API level 1

Boolean(s: String?)

Deprecated: It is rarely appropriate to use this constructor. Use parseBoolean(java.lang.String) to convert a string to a boolean primitive, or use valueOf(java.lang.String) to convert a string to a Boolean object.

Allocates a 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.

Parameters
s	String?: the string to be converted to a Boolean.

Public methods

booleanValue

Added in API level 1

fun booleanValue(): Boolean

Returns the value of this Boolean object as a boolean primitive.

Return
Boolean	the primitive boolean value of this object.

compare

Added in API level 19

static fun compare(
    x: Boolean, 
    y: Boolean
): Int

Compares two boolean values. The value returned is identical to what would be returned by:

Boolean.valueOf(x).compareTo(Boolean.valueOf(y))
  

Parameters
x	Boolean: the first boolean to compare
y	Boolean: the second boolean to compare

Return
Int	the value 0 if x == y; a value less than 0 if !x && y; and a value greater than 0 if x && !y

compareTo

Added in API level 1

fun compareTo(other: Boolean): Int

Compares this Boolean instance with another.

Parameters
o	the object to be compared.
b	the Boolean instance to be compared

Return
Int	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

Exceptions
java.lang.NullPointerException	if the argument is null
java.lang.ClassCastException	if the specified object's type prevents it from being compared to this object.

See Also

• java.lang.Comparable

equals

Added in API level 1

fun equals(other: Any?): Boolean

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.

Parameters
obj	the object to compare with.

Return
Boolean	true if the Boolean objects represent the same value; false otherwise.

getBoolean

Added in API level 1

static fun getBoolean(name: String): Boolean

Returns 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.

Parameters
name	String: the system property name.

Return
Boolean	the boolean value of the system property.

Exceptions
java.lang.SecurityException	for the same reasons as System.getProperty

See Also

• java.lang.System#getProperty(java.lang.String)
• java.lang.System#getProperty(java.lang.String, java.lang.String)

hashCode

Added in API level 1

fun hashCode(): Int

Returns a hash code for this Boolean object.

Return
Int	the integer 1231 if this object represents true; returns the integer 1237 if this object represents false.

hashCode

Added in API level 24

static fun hashCode(value: Boolean): Int

Returns a hash code for a boolean value; compatible with Boolean.hashCode().

Parameters
value	Boolean: the value to hash

Return
Int	a hash code value for a boolean value.

logicalAnd

Added in API level 24

static fun logicalAnd(
    a: Boolean, 
    b: Boolean
): Boolean

Returns the result of applying the logical AND operator to the specified boolean operands.

Parameters
a	Boolean: the first operand
b	Boolean: the second operand

Return
Boolean	the logical AND of a and b

See Also

• java.util.function.BinaryOperator

logicalOr

Added in API level 24

static fun logicalOr(
    a: Boolean, 
    b: Boolean
): Boolean

Returns the result of applying the logical OR operator to the specified boolean operands.

Parameters
a	Boolean: the first operand
b	Boolean: the second operand

Return
Boolean	the logical OR of a and b

See Also

• java.util.function.BinaryOperator

logicalXor

Added in API level 24

static fun logicalXor(
    a: Boolean, 
    b: Boolean
): Boolean

Returns the result of applying the logical XOR operator to the specified boolean operands.

Parameters
a	Boolean: the first operand
b	Boolean: the second operand

Return
Boolean	the logical XOR of a and b

See Also

• java.util.function.BinaryOperator

parseBoolean

Added in API level 1

static fun parseBoolean(s: String?): Boolean

Parses the string argument as a boolean. The 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.

Parameters
s	String?: the String containing the boolean representation to be parsed

Return
Boolean	the boolean represented by the string argument

toString

Added in API level 1

fun toString(): String

Returns a 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.

Return
String	a string representation of this object.

toString

Added in API level 1

static fun toString(b: Boolean): String

Returns a 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.

Parameters
b	Boolean: the boolean to be converted

Return
String	the string representation of the specified boolean

valueOf

Added in API level 1

static fun valueOf(b: Boolean): Boolean

Returns a 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.

Parameters
b	Boolean: a boolean value.

Return
Boolean	a Boolean instance representing b.

valueOf

Added in API level 1

static fun valueOf(s: String?): Boolean

Returns a 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.

Parameters
s	String?: a string.

Return
Boolean	the Boolean value represented by the string.

Properties

FALSE

Added in API level 1

static val FALSE: Boolean!

The Boolean object corresponding to the primitive value false.

TRUE

Added in API level 1

static val TRUE: Boolean!

The Boolean object corresponding to the primitive value true.

TYPE

Added in API level 1

static val TYPE: Class<Boolean!>!

The Class object representing the primitive type boolean.