java.lang.Object | +--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 . |
Constructor Summary | |
Long(long value)
Constructs a newly allocated Long object that
represents the primitive long argument. |
Method Summary | |
boolean |
equals(Object obj)
Compares this object against the specified object. |
int |
hashCode()
Computes a hashcode for this Long. |
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. |
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. |
Methods inherited from class java.lang.Object |
getClass,
notify,
notifyAll,
wait,
wait,
wait |
Field Detail |
public static final long MIN_VALUE
long
.public static final long MAX_VALUE
long
.Constructor Detail |
public Long(long value)
Long
object that
represents the primitive long
argument.value
- the value to be represented by the
Long
object.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 radix-N digits in the order shown. Thus, the digits for hexadecimal (radix 16) are 0123456789abcdef.0123456789abcdefghijklmnopqrstuvwxyz
i
- a long.radix
- the radix.Character.MAX_RADIX
,
Character.MIN_RADIX
public static String toString(long i)
toString(long, 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 long longValue()
long
value represented by this object.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.