public final class Long extends Number implements Comparable<Long>
Long
class wraps a value of the primitive type long
in an object. An object
of type Long
contains a single field whose type is long
.
In addition, this class provides several methods for converting a long
to a
String
and a String
to a long
, as well as other constants and methods
useful when dealing with a long
.
Modifier and Type  Field and Description 

static long 
MAX_VALUE
A constant holding the maximum value a
long can have, 2^{63}1. 
static long 
MIN_VALUE
A constant holding the minimum value a
long can have, 2^{63}. 
static int 
SIZE
The number of bits used to represent a
long value in two's complement binary form. 
Constructor and Description 

Long(long value)
Constructs a newly allocated
Long object that represents the specified long
argument. 
Long(String s)
Constructs a newly allocated
Long object that represents the long value
indicated by the String parameter. 
Modifier and Type  Method and Description 

byte 
byteValue()
Returns the value of this
Long as a byte . 
static int 
compare(long x,
long y)
Compares two
long values numerically. 
int 
compareTo(Long anotherLong)
Compares two
Long objects numerically. 
static Long 
decode(String nm)
Decodes a
String into a Long . 
double 
doubleValue()
Returns the value of this
Long as a double . 
boolean 
equals(Object obj)
Compares this object to the specified object.

float 
floatValue()
Returns the value of this
Long as a float . 
static Long 
getLong(String nm)
Determines the
long value of the system property with the specified name. 
static Long 
getLong(String nm,
long val)
Determines the
long value of the system property with the specified name. 
static Long 
getLong(String nm,
Long val)
Returns the
long value of the system property with the specified name. 
int 
hashCode()
Returns a hash code for this
Long . 
int 
intValue()
Returns the value of this
Long as an int . 
long 
longValue()
Returns the value of this
Long as a long value. 
static long 
parseLong(String s)
Parses the string argument as a signed decimal
long . 
static long 
parseLong(String s,
int radix)
Parses the string argument as a signed
long in the radix specified by the second
argument. 
static long 
rotateLeft(long i,
int distance)
Returns the value obtained by rotating the two's complement binary representation of the
specified
long value left by the specified number of bits. 
static long 
rotateRight(long i,
int distance)
Returns the value obtained by rotating the two's complement binary representation of the
specified
long value right by the specified number of bits. 
short 
shortValue()
Returns the value of this
Long as a short . 
static int 
signum(long i)
Returns the signum function of the specified
long value. 
static String 
toBinaryString(long i)
Returns a string representation of the
long argument as an unsigned integer in
base 2. 
static String 
toHexString(long i)
Returns a string representation of the
long argument as an unsigned integer in
base 16. 
String 
toString()
Returns a
String object representing this Long 's value. 
static String 
toString(long i)
Returns a
String object representing the specified long . 
static String 
toString(long i,
int radix)
Returns a string representation of the first argument in the radix specified by the second
argument.

static Long 
valueOf(long l)
Returns a
Long instance representing the specified long value. 
static Long 
valueOf(String s)
Returns a
Long object holding the value of the specified String . 
static Long 
valueOf(String s,
int radix)
Returns a
Long object holding the value extracted from the specified String
when parsed with the radix given by the second argument. 
public static final long MAX_VALUE
long
can have, 2^{63}1.public static final long MIN_VALUE
long
can have, 2^{63}.public static final int SIZE
long
value in two's complement binary form.public Long(long value)
Long
object that represents the specified long
argument.value
 the value to be represented by the Long
object.public Long(String s) throws NumberFormatException
Long
object that represents the long
value
indicated by the String
parameter. The string is converted to a long
value in
exactly the manner used by the parseLong
method for radix 10.s
 the String
to be converted to a Long
.NumberFormatException
 if the String
does not contain a parsable long
.parseLong(java.lang.String, int)
public static int compare(long x, long y)
long
values numerically. The value returned is identical to what would
be returned by:
Long.valueOf(x).compareTo(Long.valueOf(y))
x
 the first long
to comparey
 the second long
to compare0
if x == y
; a value less than 0
if x < y
;
and a value greater than 0
if x > y
public static Long decode(String nm) throws NumberFormatException
String
into a Long
. Accepts decimal, hexadecimal, and octal numbers
given by the following grammar:
DecimalNumeral, HexDigits, and OctalDigits are as defined in section 3.10.1 of The Java™ Language Specification, except that underscores are not accepted between digits.
 DecodableString:
 Sign_{opt} DecimalNumeral
 Sign_{opt}
0x
HexDigits Sign_{opt}
0X
HexDigits Sign_{opt}
#
HexDigits Sign_{opt}
0
OctalDigits
 Sign:

+
The sequence of characters following an optional sign and/or radix specifier ("0x
", "
0X
", "#
", or leading zero) is parsed as by the Long.parseLong
method
with the indicated radix (10, 16, or 8). This sequence of characters must represent a
positive value or a NumberFormatException
will be thrown. The result is negated if
first character of the specified String
is the minus sign. No whitespace characters
are permitted in the String
.
nm
 the String
to decode.Long
object holding the long
value represented by nm
NumberFormatException
 if the String
does not contain a parsable long
.parseLong(String, int)
public static Long getLong(String nm)
long
value of the system property with the specified name.
The first argument is treated as the name of a system property. System properties are
accessible through the System.getProperty(java.lang.String)
method. The
string value of this property is then interpreted as a long
value and a Long
object representing this value is returned. Details of possible numeric formats can be found
with the definition of getProperty
.
If there is no property with the specified name, if the specified name is empty or
null
, or if the property does not have the correct numeric format, then null
is returned.
In other words, this method returns a Long
object equal to the value of:
getLong(nm, null)
nm
 property name.Long
value of the property.System.getProperty(java.lang.String)
,
System.getProperty(java.lang.String, java.lang.String)
public static Long getLong(String nm, long val)
long
value of the system property with the specified name.
The first argument is treated as the name of a system property. System properties are
accessible through the System.getProperty(java.lang.String)
method. The
string value of this property is then interpreted as a long
value and a Long
object representing this value is returned. Details of possible numeric formats can be found
with the definition of getProperty
.
The second argument is the default value. A Long
object that represents the value of
the second argument is returned if there is no property of the specified name, if the
property does not have the correct numeric format, or if the specified name is empty or null.
In other words, this method returns a Long
object equal to the value of:
getLong(nm, new Long(val))
but in practice it may be implemented in a manner such as:
to avoid the unnecessary allocation of aLong result = getLong(nm, null); return (result == null) ? new Long(val) : result;
Long
object when the default value is not
needed.nm
 property name.val
 default value.Long
value of the property.System.getProperty(java.lang.String)
,
System.getProperty(java.lang.String, java.lang.String)
public static Long getLong(String nm, Long val)
long
value of the system property with the specified name. The first
argument is treated as the name of a system property. System properties are accessible
through the System.getProperty(java.lang.String)
method. The string value
of this property is then interpreted as a long
value, as per the Long.decode
method, and a Long
object representing this value is returned.
0x
or the ASCII
character #
, not followed by a minus sign, then the rest of it is parsed as a
hexadecimal integer exactly as for the method valueOf(java.lang.String, int)
with
radix 16.
0
followed by another
character, it is parsed as an octal integer exactly as by the method
valueOf(java.lang.String, int)
with radix 8.
valueOf(java.lang.String, int)
with radix 10.
Note that, in every case, neither L
('\u004C'
) nor l
(
'\u006C'
) is permitted to appear at the end of the property value as a type
indicator, as would be permitted in Java programming language source code.
The second argument is the default value. The default value is returned if there is no
property of the specified name, if the property does not have the correct numeric format, or
if the specified name is empty or null
.
nm
 property name.val
 default value.Long
value of the property.System.getProperty(java.lang.String)
,
System.getProperty(java.lang.String, java.lang.String)
,
decode(java.lang.String)
public static long parseLong(String s) throws NumberFormatException
long
. The characters in the string
must all be decimal digits, except that the first character may be an ASCII minus sign
''
(\u002D'
) to indicate a negative value or an ASCII plus sign
'+'
('\u002B'
) to indicate a positive value. The resulting
long
value is returned, exactly as if the argument and the radix 10
were
given as arguments to the parseLong(java.lang.String, int)
method.
Note that neither the character L
('\u004C'
) nor l
(
'\u006C'
) is permitted to appear at the end of the string as a type
indicator, as would be permitted in Java programming language source code.
s
 a String
containing the long
representation to be parsedlong
represented by the argument in decimal.NumberFormatException
 if the string does not contain a parsable long
.public static long parseLong(String s, int radix) throws NumberFormatException
long
in the radix specified by the second
argument. The characters in the string must all be digits of the specified radix (as
determined by whether Character.digit(char, int)
returns a nonnegative
value), except that the first character may be an ASCII minus sign ''
(
'\u002D'
) to indicate a negative value or an ASCII plus sign '+'
(
'\u002B'
) to indicate a positive value. The resulting long
value is
returned.
Note that neither the character L
('\u004C'
) nor l
(
'\u006C'
) is permitted to appear at the end of the string as a type
indicator, as would be permitted in Java programming language source code  except that
either L
or l
may appear as a digit for a radix greater than 22.
An exception of type NumberFormatException
is thrown if any of the following
situations occurs:
null
or is a string of length zero.
radix
is either smaller than Character.MIN_RADIX
or larger
than Character.MAX_RADIX
.
''
('\u002d'
) or plus sign
'+'
('\u002B'
) provided that the string is longer than length 1.
long
.
Examples:
parseLong("0", 10) returns 0L parseLong("473", 10) returns 473L parseLong("+42", 10) returns 42L parseLong("0", 10) returns 0L parseLong("FF", 16) returns 255L parseLong("1100110", 2) returns 102L parseLong("99", 8) throws a NumberFormatException parseLong("Hazelnut", 10) throws a NumberFormatException parseLong("Hazelnut", 36) returns 1356099454469L
s
 the String
containing the long
representation to be parsed.radix
 the radix to be used while parsing s
.long
represented by the string argument in the specified radix.NumberFormatException
 if the string does not contain a parsable long
.public static long rotateLeft(long i, int distance)
long
value left by the specified number of bits. (Bits shifted out of the
left hand, or highorder, side reenter on the right, or loworder.)
Note that left rotation with a negative distance is equivalent to right rotation:
rotateLeft(val, distance) == rotateRight(val,
distance)
. Note also that rotation by any multiple of 64 is a noop, so all but the last six
bits of the rotation distance can be ignored, even if the distance is negative:
rotateLeft(val,
distance) == rotateLeft(val, distance & 0x3F)
.
long
value left by the specified number of bits.public static long rotateRight(long i, int distance)
long
value right by the specified number of bits. (Bits shifted out of the
right hand, or loworder, side reenter on the left, or highorder.)
Note that right rotation with a negative distance is equivalent to left rotation:
rotateRight(val, distance) == rotateLeft(val,
distance)
. Note also that rotation by any multiple of 64 is a noop, so all but the last six
bits of the rotation distance can be ignored, even if the distance is negative:
rotateRight(val,
distance) == rotateRight(val, distance & 0x3F)
.
long
value right by the specified number of bits.public static int signum(long i)
long
value. (The return value is 1 if
the specified value is negative; 0 if the specified value is zero; and 1 if the specified
value is positive.)long
value.public static String toBinaryString(long i)
long
argument as an unsigned integer in
base 2.
The unsigned long
value is the argument plus 2^{64} if the argument is
negative; otherwise, it is equal to the argument. This value is converted to a string of
ASCII digits in binary (base 2) with no extra leading 0
s. If the unsigned
magnitude is zero, it is represented by a single zero character '0'
(
'\u0030'
); otherwise, the first character of the representation of the
unsigned magnitude will not be the zero character. The characters '0'
(
'\u0030'
) and '1'
('\u0031'
) are used as binary
digits.
i
 a long
to be converted to a string.long
value represented by the
argument in binary (base 2).public static String toHexString(long i)
long
argument as an unsigned integer in
base 16.
The unsigned long
value is the argument plus 2^{64} if the argument is
negative; otherwise, it is equal to the argument. This value is converted to a string of
ASCII digits in hexadecimal (base 16) with no extra leading 0
s. If the unsigned
magnitude is zero, it is represented by a single zero character '0'
(
'\u0030'
); otherwise, the first character of the representation of the
unsigned magnitude will not be the zero character. The following characters are used as
hexadecimal digits:
0123456789abcdef
These are the characters '\u0030'
through '\u0039'
and
'\u0061'
through '\u0066'
. If uppercase letters are
desired, the String.toUpperCase()
method may be called on the result:
Long.toHexString(n).toUpperCase()
i
 a long
to be converted to a string.long
value represented by the
argument in hexadecimal (base 16).public static String toString(long i)
String
object representing the specified long
. The argument is
converted to signed decimal representation and returned as a string, exactly as if the
argument and the radix 10 were given as arguments to the toString(long, int)
method.i
 a long
to be converted.public static String toString(long i, int radix)
If the radix is smaller than Character.MIN_RADIX
or larger than
Character.MAX_RADIX
, then the radix 10
is used instead.
If the first argument is negative, the first element of the result is the ASCII minus sign
''
('\u002d'
). If the first argument is not negative, no sign
character appears in the result.
The remaining characters of the result represent the magnitude of the first argument. If the
magnitude is zero, it is represented by a single zero character '0'
(
'\u0030'
); otherwise, the first character of the representation of the
magnitude will not be the zero character. The following ASCII characters are used as digits:
0123456789abcdefghijklmnopqrstuvwxyz
These are '\u0030'
through '\u0039'
and
'\u0061'
through '\u007a'
. If radix
is
N, then the first N of these characters are used as radixN
digits in the order shown. Thus, the digits for hexadecimal (radix 16) are
0123456789abcdef
. If uppercase letters are desired, the
String.toUpperCase()
method may be called on the result:
Long.toString(n, 16).toUpperCase()
i
 a long
to be converted to a string.radix
 the radix to use in the string representation.Character.MAX_RADIX
,
Character.MIN_RADIX
public static Long valueOf(long l)
Long
instance representing the specified long
value. If a new
Long
instance is not required, this method should generally be used in preference to
the constructor Long(long)
, as this method is likely to yield significantly better
space and time performance by caching frequently requested values.
Note that unlike the corresponding method in the
Integer
class, this method is not required to cache values within a
particular range.l
 a long value.Long
instance representing l
.public static Long valueOf(String s) throws NumberFormatException
Long
object holding the value of the specified String
. The argument
is interpreted as representing a signed decimal long
, exactly as if the argument were
given to the parseLong(java.lang.String)
method. The result is a Long
object
that represents the integer value specified by the string.
In other words, this method returns a Long
object equal to the value of:
new Long(Long.parseLong(s))
s
 the string to be parsed.Long
object holding the value represented by the string argument.NumberFormatException
 If the string cannot be parsed as a long
.public static Long valueOf(String s, int radix) throws NumberFormatException
Long
object holding the value extracted from the specified String
when parsed with the radix given by the second argument. The first argument is interpreted as
representing a signed long
in the radix specified by the second argument, exactly as
if the arguments were given to the parseLong(java.lang.String, int)
method. The
result is a Long
object that represents the long
value specified by the
string.
In other words, this method returns a Long
object equal to the value of:
new Long(Long.parseLong(s, radix))
s
 the string to be parsedradix
 the radix to be used in interpreting s
Long
object holding the value represented by the string argument in the
specified radix.NumberFormatException
 If the String
does not contain a parsable long
.public byte byteValue()
Long
as a byte
.public int compareTo(Long anotherLong)
Long
objects numerically.compareTo
in interface Comparable<Long>
anotherLong
 the Long
to be compared.0
if this Long
is equal to the argument Long
; a
value less than 0
if this Long
is numerically less than the argument
Long
; and a value greater than 0
if this Long
is numerically
greater than the argument Long
(signed comparison).public double doubleValue()
Long
as a double
.doubleValue
in class Number
double
.public boolean equals(Object obj)
true
if and only if the
argument is not null
and is a Long
object that contains the same long
value as this object.equals
in class Object
obj
 the object to compare with.true
if the objects are the same; false
otherwise.Object.hashCode()
,
HashMap
public float floatValue()
Long
as a float
.floatValue
in class Number
float
.public int hashCode()
Long
. The result is the exclusive OR of the two halves
of the primitive long
value held by this Long
object. That is, the hashcode
is the value of the expression:
(int)(this.longValue()^(this.longValue()>>>32))
hashCode
in class Object
Object.equals(java.lang.Object)
,
System.identityHashCode(java.lang.Object)
public int intValue()
Long
as an int
.public long longValue()
Long
as a long
value.public short shortValue()
Long
as a short
.shortValue
in class Number
short
.public String toString()
String
object representing this Long
's value. The value is
converted to signed decimal representation and returned as a string, exactly as if the
long
value were given as an argument to the toString(long)
method.