
Java^{TM} 2 Platform Standard Edition 

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SUMMARY: INNER  FIELD  CONSTR  METHOD  DETAIL: FIELD  CONSTR  METHOD 
java.lang.Object  +java.lang.Number  +java.lang.Long
The 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
.
Field Summary  
static long 
MAX_VALUE
The largest value of type long . 
static long 
MIN_VALUE
The smallest value of type long . 
static Class 
TYPE
The Class object representing the primitive type long. 
Constructor Summary  
Long(long value)
Constructs a newly allocated Long object that
represents the primitive long argument. 

Long(String s)
Constructs a newly allocated Long object that
represents the value represented by the string in decimal form. 
Method Summary  
byte 
byteValue()
Returns the value of this Long as a byte. 
int 
compareTo(Long anotherLong)
Compares two Longs numerically. 
int 
compareTo(Object o)
Compares this Long to another Object. 
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 against 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()
Computes a hashcode 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. 
short 
shortValue()
Returns the value of this Long as a short. 
static String 
toBinaryString(long i)
Creates a string representation of the long argument as an unsigned integer in base 2. 
static String 
toHexString(long i)
Creates a string representation of the long argument as an unsigned integer in base 16. 
static String 
toOctalString(long i)
Creates a string representation of the long argument as an unsigned integer in base 8. 
String 
toString()
Returns a String object representing this Long's value. 
static String 
toString(long i)
Returns a new String object representing the specified integer. 
static String 
toString(long i,
int radix)
Creates a string representation of the first argument in the radix specified by the second argument. 
static Long 
valueOf(String s)
Returns a new long object initialized to the value of the specified String. 
static Long 
valueOf(String s,
int radix)
Returns a new long object initialized to the value of the specified String. 
Methods inherited from class java.lang.Object 
clone,
finalize,
getClass,
notify,
notifyAll,
wait,
wait,
wait 
Field Detail 
public static final long MIN_VALUE
long
.public static final long MAX_VALUE
long
.public static final Class TYPE
Constructor Detail 
public Long(long value)
Long
object that
represents the primitive long
argument.value
 the value to be represented by the
Long
object.public Long(String s) throws NumberFormatException
Long
object that
represents the value represented by the string in decimal form.
The string is converted to an long
value as if by the
parseLong(java.lang.String, int)
method for radix 10.s
 the string to be converted to a Long
.String
does not
contain a parsable long integer.valueOf(java.lang.String)
Method Detail 
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:
These are '\u0030' through '\u0039' and '\u0061' through '\u007a'. If the 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, the0123456789abcdefghijklmnopqrstuvwxyz
String.toUpperCase()
method
may be called on the result:
Long.toString(n, 16).toUpperCase()
i
 a long.radix
 the radix.Character.MAX_RADIX
,
Character.MIN_RADIX
public static String toHexString(long i)
The unsigned long value is the argument plus 2^{64} if the argument is negative; otherwise, it is equal to the argument.
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:
These are the characters '\u0030' through '\u0039' and '\u0061' through '\u0066'. If uppercase letters are desired, the0123456789abcdef
String.toUpperCase()
method may be called on
the result:
Long.toHexString(n).toUpperCase()
i
 a long
.public static String toOctalString(long i)
The unsigned long value is the argument plus 2^{64} if the argument is negative; otherwise, it is equal to the argument.
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 octal digits:
These are the characters '\u0030' through '\u0037'.01234567
i
 a long
.public static String toBinaryString(long i)
The unsigned long value is the argument plus 2^{64} if the argument is negative; otherwise, it is equal to the argument.
If the unsigned magnitude is zero, it is represented by a single zero character '0' ('&392;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.public static String toString(long i)
#toString(java.lang.String, int)
method that takes two
arguments.i
 a long
to be converted.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
returns a
nonnegative value), except that the first character may be an
ASCII minus sign ''
('\u002d' to indicate
a negative value. The resulting long
value is returned.
Note that neither L nor l 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:
Character.MIN_RADIX
or larger than
Character.MAX_RADIX
.
Examples:
parseLong("0", 10) returns 0L parseLong("473", 10) returns 473L 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
.radix
 the radix to be used.long
represented by the string argument in
the specified radix.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. The resulting long value is returned, exactly as if the
argument and the radix 10 were given as arguments to the
parseLong(String, int)
method that takes two arguments.
Note that neither L nor l 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.long
represented by the argument in decimal.long
.public static Long valueOf(String s, int radix) throws NumberFormatException
The first argument is interpreted as representing a signed integer
in the radix specified by the second argument, exactly as if the
arguments were given to the parseLong(java.lang.String, int)
method that takes two arguments. 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, radix))
s
 the String
containing the
long
.radix
 the radix to be used.Long
initialized to the
value represented by the string argument in the specified
radix.String
does not
contain a parsable long
.public static Long valueOf(String s) throws NumberFormatException
The argument is interpreted as representing a signed decimal
integer, exactly as if the argument were given to the
parseLong(java.lang.String)
method that takes one argument).
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
initialized to the
value represented by the string argument.String
does not
contain a parsable long
.public static Long decode(String nm) throws NumberFormatException
String
into a Long
. Accepts
decimal, hexadecimal, and octal numbers, in the following formats:
[]The constant following an (optional) negative sign and/or "radix specifier" is parsed as by the[] 0x [] # [] 0
Long.parseLong
method
with the specified radix (10, 8 or 16). This constant must be positive
or a NumberFormatException will result. The result is made negative if
first character of the specified String
is the negative
sign. No whitespace characters are permitted in the
String
.nm
 the String
to decode.Long
represented by the specified string.String
does not
contain a parsable long.parseLong(String, int)
public byte byteValue()
public short shortValue()
public int intValue()
long
value represented by this object is
converted to type int
and the result of the
conversion is returned.public long longValue()
long
value represented by this object.public float floatValue()
long
value represented by this object is
converted to type float
and the result of
the conversion is returned.public double doubleValue()
long
value represented by this object that
is converted to type double
and the result of
the conversion is returned.public String toString()
toString(long)
method that takes one argument.public int hashCode()
long
value
represented by this Long
object. That is, the hashcode
is the value of the expression:
(int)(this.longValue()^(this.longValue()>>>32))
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.obj
 the object to compare with.true
if the objects are the same;
false
otherwise.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, 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
java.lang.System#getProperty()
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, or if the
property does not have the correct numeric format, then a
Long
object that represents the value of the second
argument is returned.
In other words, this method returns a Long object equal to the value of:
but in practice it may be implemented in a manner such as:getLong(nm, new Long(val))
to avoid the unnecessary allocation of a Long object when the default value is not needed.Long result = getLong(nm, null); return (result == null) ? new Long(val) : result;
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)
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.
valueOf(java.lang.String, int)
with radix 16.
valueOf(java.lang.String, int)
with radix 8.
valueOf(java.lang.String, int)
with radix 10.
Note that, in every case, neither L nor l 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. If there is no property of the specified name, or if the property does not have the correct numeric format, then the second argument is returned.
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 int compareTo(Long anotherLong)
anotherLong
 the Long
to be compared.0
if the argument Long is equal to
this Long; a value less than 0
if this Long
is numerically less than the Long argument; and a
value greater than 0
if this Long is
numerically greater than the Long argument
(signed comparison).public int compareTo(Object o)
compareTo(Long)
. Otherwise,
it throws a ClassCastException
(as Longs are comparable
only to other Longs).o
 the Object
to be compared.0
if the argument is a Long
numerically equal to this Long; a value less than
0
if the argument is a Long numerically
greater than this Long; and a value greater than
0
if the argument is a Long numerically
less than this Long.ClassCastException
 if the argument is not a
Long
.Comparable

Java^{TM} 2 Platform Standard Edition 

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