java.lang.Object | +--java.lang.Integer
The Integer class wraps a value of the primitive type int
in an object. An object of type Integer
contains a
single field whose type is int
.
In addition, this class provides several methods for converting
an int
to a String
and a
String
to an int
, as well as other
constants and methods useful when dealing with an
int
.
Field Summary | |
static int |
MAX_VALUE
The largest value of type int . |
static int |
MIN_VALUE
The smallest value of type int . |
Constructor Summary | |
Integer(int value)
Constructs a newly allocated Integer object that
represents the primitive int argument. |
Method Summary | |
byte |
byteValue()
Returns the value of this Integer as a byte. |
boolean |
equals(Object obj)
Compares this object to the specified object. |
int |
hashCode()
Returns a hashcode for this Integer. |
int |
intValue()
Returns the value of this Integer as an int. |
long |
longValue()
Returns the value of this Integer as a long. |
static int |
parseInt(String s)
Parses the string argument as a signed decimal integer. |
static int |
parseInt(String s,
int radix)
Parses the string argument as a signed integer in the radix specified by the second argument. |
short |
shortValue()
Returns the value of this Integer as a short. |
static String |
toBinaryString(int i)
Creates a string representation of the integer argument as an unsigned integer in base 2. |
static String |
toHexString(int i)
Creates a string representation of the integer argument as an unsigned integer in base 16. |
static String |
toOctalString(int i)
Creates a string representation of the integer argument as an unsigned integer in base 8. |
String |
toString()
Returns a String object representing this Integer's value. |
static String |
toString(int i)
Returns a new String object representing the specified integer. |
static String |
toString(int i,
int radix)
Creates a string representation of the first argument in the radix specified by the second argument. |
static Integer |
valueOf(String s)
Returns a new Integer object initialized to the value of the specified String. |
static Integer |
valueOf(String s,
int radix)
Returns a new Integer object initialized to the value of the specified String. |
Methods inherited from class java.lang.Object |
getClass,
notify,
notifyAll,
wait,
wait,
wait |
Field Detail |
public static final int MIN_VALUE
int
. The constant
value of this field is -2147483648.public static final int MAX_VALUE
int
. The constant
value of this field is 2147483647.Constructor Detail |
public Integer(int value)
Integer
object that
represents the primitive int
argument.value
- the value to be represented by the Integer
.Method Detail |
public static String toString(int 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 character '-'
('\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
- an integer.radix
- the radix.Character.MAX_RADIX
,
Character.MIN_RADIX
public static String toHexString(int i)
The unsigned integer value is the argument plus 2^{32} 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:
These are the characters '\u0030' through '\u0039' and 'u\0039' through '\u0066'.0123456789abcdef
i
- an integer.public static String toOctalString(int i)
The unsigned integer value is the argument plus 2^{32} if
the argument is negative; otherwise, it is equal to the argument.
This value is converted to a string of ASCII digits in octal
(base 8) 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 octal digits are:
These are the characters '\u0030' through '\u0037'.01234567
i
- an integerpublic static String toBinaryString(int i)
The unsigned integer value is the argument plus 2^{32}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
- an integer.public static String toString(int i)
toString(int, int)
method.i
- an integer to be converted.public static int parseInt(String s, int radix) throws NumberFormatException
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. The resulting integer value is returned.
An exception of type NumberFormatException is thrown if any of the following situations occurs:
Character.MIN_RADIX
or
larger than Character.MAX_RADIX
.
Examples:
parseInt("0", 10) returns 0 parseInt("473", 10) returns 473 parseInt("-0", 10) returns 0 parseInt("-FF", 16) returns -255 parseInt("1100110", 2) returns 102 parseInt("2147483647", 10) returns 2147483647 parseInt("-2147483648", 10) returns -2147483648 parseInt("2147483648", 10) throws a NumberFormatException parseInt("99", 8) throws a NumberFormatException parseInt("Kona", 10) throws a NumberFormatException parseInt("Kona", 27) returns 411787
s
- the String
containing the integer.radix
- the radix to be used.public static int parseInt(String s) throws NumberFormatException
'-'
('\u002d') to indicate a negative value. The resulting
integer value is returned, exactly as if the argument and the radix
10 were given as arguments to the
parseInt(java.lang.String, int)
method.s
- a string.public static Integer valueOf(String s, int radix) throws NumberFormatException
parseInt(java.lang.String, int)
method. The result is an
Integer
object that represents the integer value
specified by the string.
In other words, this method returns an Integer
object
equal to the value of:
new Integer(Integer.parseInt(s, radix))
s
- the string to be parsed.radix
- the radix of the integer represented by string
sInteger
initialized to the
value represented by the string argument in the specified
radix.int
.public static Integer valueOf(String s) throws NumberFormatException
parseInt(java.lang.String)
method. The result is an
Integer object that represents the integer value specified
by the string.
In other words, this method returns an Integer object equal to the value of:
new Integer(Integer.parseInt(s))
s
- the string to be parsed.Integer
initialized to the
value represented by the string argument.public byte byteValue()
public short shortValue()
public int intValue()
int
value represented by this object.public long longValue()
int
value represented by this object that is
converted to type long
and the result of the
conversion is returned.public String toString()
toString(int)
method.public int hashCode()
public boolean equals(Object obj)
true
if and only if the argument is not
null
and is an Integer
object that contains
the same int
value as this object.obj
- the object to compare with.true
if the objects are the same;
false
otherwise.