Integer
public
final
class
Integer
extends Number
implements
Comparable<Integer>
java.lang.Object  
↳  java.lang.Number  
↳  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
.
Implementation note: The implementations of the "bit twiddling"
methods (such as highestOneBit
and
numberOfTrailingZeros
) are
based on material from Henry S. Warren, Jr.'s Hacker's
Delight, (Addison Wesley, 2002).
Summary
Constants  

int 
BYTES
The number of bytes used to represent a 
int 
MAX_VALUE
A constant holding the maximum value an 
int 
MIN_VALUE
A constant holding the minimum value an 
int 
SIZE
The number of bits used to represent an 
Fields  

public
static
final
Class<Integer> 
TYPE
The 
Public constructors  

Integer(int value)
Constructs a newly allocated 

Integer(String s)
Constructs a newly allocated 
Public methods  

static
int

bitCount(int i)
Returns the number of onebits in the two's complement binary
representation of the specified 
byte

byteValue()
Returns the value of this 
static
int

compare(int x, int y)
Compares two 
int

compareTo(Integer anotherInteger)
Compares two 
static
int

compareUnsigned(int x, int y)
Compares two 
static
Integer

decode(String nm)
Decodes a 
static
int

divideUnsigned(int dividend, int divisor)
Returns the unsigned quotient of dividing the first argument by the second where each argument and the result is interpreted as an unsigned value. 
double

doubleValue()
Returns the value of this 
boolean

equals(Object obj)
Compares this object to the specified object. 
float

floatValue()
Returns the value of this 
static
Integer

getInteger(String nm, Integer val)
Returns the integer value of the system property with the specified name. 
static
Integer

getInteger(String nm)
Determines the integer value of the system property with the specified name. 
static
Integer

getInteger(String nm, int val)
Determines the integer value of the system property with the specified name. 
int

hashCode()
Returns a hash code for this 
static
int

hashCode(int value)
Returns a hash code for a 
static
int

highestOneBit(int i)
Returns an 
int

intValue()
Returns the value of this 
long

longValue()
Returns the value of this 
static
int

lowestOneBit(int i)
Returns an 
static
int

max(int a, int b)
Returns the greater of two 
static
int

min(int a, int b)
Returns the smaller of two 
static
int

numberOfLeadingZeros(int i)
Returns the number of zero bits preceding the highestorder
("leftmost") onebit in the two's complement binary representation
of the specified 
static
int

numberOfTrailingZeros(int i)
Returns the number of zero bits following the lowestorder ("rightmost")
onebit in the two's complement binary representation of the specified

static
int

parseInt(String s, int radix)
Parses the string argument as a signed integer in the radix specified by the second argument. 
static
int

parseInt(String s)
Parses the string argument as a signed decimal integer. 
static
int

parseUnsignedInt(String s)
Parses the string argument as an unsigned decimal integer. 
static
int

parseUnsignedInt(String s, int radix)
Parses the string argument as an unsigned integer in the radix specified by the second argument. 
static
int

remainderUnsigned(int dividend, int divisor)
Returns the unsigned remainder from dividing the first argument by the second where each argument and the result is interpreted as an unsigned value. 
static
int

reverse(int i)
Returns the value obtained by reversing the order of the bits in the
two's complement binary representation of the specified 
static
int

reverseBytes(int i)
Returns the value obtained by reversing the order of the bytes in the
two's complement representation of the specified 
static
int

rotateLeft(int i, int distance)
Returns the value obtained by rotating the two's complement binary
representation of the specified 
static
int

rotateRight(int i, int distance)
Returns the value obtained by rotating the two's complement binary
representation of the specified 
short

shortValue()
Returns the value of this 
static
int

signum(int i)
Returns the signum function of the specified 
static
int

sum(int a, int b)
Adds two integers together as per the + operator. 
static
String

toBinaryString(int i)
Returns a string representation of the integer argument as an unsigned integer in base 2. 
static
String

toHexString(int i)
Returns a string representation of the integer argument as an unsigned integer in base 16. 
static
String

toOctalString(int i)
Returns a string representation of the integer argument as an unsigned integer in base 8. 
String

toString()
Returns a 
static
String

toString(int i)
Returns a 
static
String

toString(int i, int radix)
Returns a string representation of the first argument in the radix specified by the second argument. 
static
long

toUnsignedLong(int x)
Converts the argument to a 
static
String

toUnsignedString(int i)
Returns a string representation of the argument as an unsigned decimal value. 
static
String

toUnsignedString(int i, int radix)
Returns a string representation of the first argument as an unsigned integer value in the radix specified by the second argument. 
static
Integer

valueOf(String s)
Returns an 
static
Integer

valueOf(String s, int radix)
Returns an 
static
Integer

valueOf(int i)
Returns an 
Inherited methods  

Constants
BYTES
public static final int BYTES
The number of bytes used to represent a int
value in two's
complement binary form.
Constant Value: 4 (0x00000004)
MAX_VALUE
public static final int MAX_VALUE
A constant holding the maximum value an int
can
have, 2^{31}1.
Constant Value: 2147483647 (0x7fffffff)
MIN_VALUE
public static final int MIN_VALUE
A constant holding the minimum value an int
can
have, 2^{31}.
Constant Value: 2147483648 (0x80000000)
SIZE
public static final int SIZE
The number of bits used to represent an int
value in two's
complement binary form.
Constant Value: 32 (0x00000020)
Fields
TYPE
public static final Class<Integer> TYPE
The Class
instance representing the primitive type
int
.
Public constructors
Integer
public Integer (int value)
Constructs a newly allocated Integer
object that
represents the specified int
value.
Parameters  

value 
int : the value to be represented by the
Integer object.

Integer
public Integer (String s)
Constructs a newly allocated Integer
object that
represents the int
value indicated by the
String
parameter. The string is converted to an
int
value in exactly the manner used by the
parseInt
method for radix 10.
Parameters  

s 
String : the String to be converted to an
Integer . 
Throws  

NumberFormatException 
if the String does not
contain a parsable integer. 
See also:
Public methods
bitCount
public static int bitCount (int i)
Returns the number of onebits in the two's complement binary
representation of the specified int
value. This function is
sometimes referred to as the population count.
Parameters  

i 
int : the value whose bits are to be counted 
Returns  

int 
the number of onebits in the two's complement binary
representation of the specified int value. 
byteValue
public byte byteValue ()
Returns the value of this Integer
as a byte
after a narrowing primitive conversion.
Returns  

byte 
the numeric value represented by this object after conversion
to type byte . 
compare
public static int compare (int x, int y)
Compares two int
values numerically.
The value returned is identical to what would be returned by:
Integer.valueOf(x).compareTo(Integer.valueOf(y))
Parameters  

x 
int : the first int to compare 
y 
int : the second int to compare 
Returns  

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
public int compareTo (Integer anotherInteger)
Compares two Integer
objects numerically.
Parameters  

anotherInteger 
Integer : the Integer to be compared. 
Returns  

int 
the value 0 if this Integer is
equal to the argument Integer ; a value less than
0 if this Integer is numerically less
than the argument Integer ; and a value greater
than 0 if this Integer is numerically
greater than the argument Integer (signed
comparison). 
compareUnsigned
public static int compareUnsigned (int x, int y)
Compares two int
values numerically treating the values
as unsigned.
Parameters  

x 
int : the first int to compare 
y 
int : the second int to compare 
Returns  

int 
the value 0 if x == y ; a value less
than 0 if x < y as unsigned values; and
a value greater than 0 if x > y as
unsigned values 
decode
public static Integer decode (String nm)
Decodes a String
into an Integer
.
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 Integer.parseInt
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
.
Parameters  

nm 
String : the String to decode. 
Returns  

Integer 
an Integer object holding the int
value represented by nm 
Throws  

NumberFormatException 
if the String does not
contain a parsable integer. 
See also:
divideUnsigned
public static int divideUnsigned (int dividend, int divisor)
Returns the unsigned quotient of dividing the first argument by the second where each argument and the result is interpreted as an unsigned value.
Note that in two's complement arithmetic, the three other
basic arithmetic operations of add, subtract, and multiply are
bitwise identical if the two operands are regarded as both
being signed or both being unsigned. Therefore separate addUnsigned
, etc. methods are not provided.
Parameters  

dividend 
int : the value to be divided 
divisor 
int : the value doing the dividing 
Returns  

int 
the unsigned quotient of the first argument divided by the second argument 
See also:
doubleValue
public double doubleValue ()
Returns the value of this Integer
as a double
after a widening primitive conversion.
Returns  

double 
the numeric value represented by this object after conversion
to type double .

equals
public boolean equals (Object obj)
Compares this object to the specified object. The result is
true
if and only if the argument is not
null
and is an Integer
object that
contains the same int
value as this object.
Parameters  

obj 
Object : the object to compare with. 
Returns  

boolean 
true if the objects are the same;
false otherwise.

floatValue
public float floatValue ()
Returns the value of this Integer
as a float
after a widening primitive conversion.
Returns  

float 
the numeric value represented by this object after conversion
to type float .

getInteger
public static Integer getInteger (String nm, Integer val)
Returns the integer 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 an
integer value, as per the decode
method,
and an Integer
object representing this value is
returned; in summary:
 If the property value begins with the two ASCII characters
0x
or the ASCII character#
, not followed by a minus sign, then the rest of it is parsed as a hexadecimal integer exactly as by the methodvalueOf(java.lang.String, int)
with radix 16.  If the property value begins with the ASCII character
0
followed by another character, it is parsed as an octal integer exactly as by the methodvalueOf(java.lang.String, int)
with radix 8.  Otherwise, the property value is parsed as a decimal integer
exactly as by the method
valueOf(java.lang.String, int)
with radix 10.
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
.
Parameters  

nm 
String : property name. 
val 
Integer : default value. 
Returns  

Integer 
the Integer value of the property. 
Throws  

SecurityException 
for the same reasons as
System.getProperty 
getInteger
public static Integer getInteger (String nm)
Determines the integer 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 an integer
value using the grammar supported by decode
and
an Integer
object representing this value is returned.
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 an Integer
object equal to the value of:
getInteger(nm, null)
Parameters  

nm 
String : property name. 
Returns  

Integer 
the Integer value of the property. 
Throws  

SecurityException 
for the same reasons as
System.getProperty 
getInteger
public static Integer getInteger (String nm, int val)
Determines the integer 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 an integer
value using the grammar supported by decode
and
an Integer
object representing this value is returned.
The second argument is the default value. An Integer
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 an Integer
object
equal to the value of:
getInteger(nm, new Integer(val))
but in practice it may be implemented in a manner such as:
to avoid the unnecessary allocation of anInteger result = getInteger(nm, null); return (result == null) ? new Integer(val) : result;
Integer
object when the default value is not needed.
Parameters  

nm 
String : property name. 
val 
int : default value. 
Returns  

Integer 
the Integer value of the property. 
Throws  

SecurityException 
for the same reasons as
System.getProperty 
hashCode
public int hashCode ()
Returns a hash code for this Integer
.
Returns  

int 
a hash code value for this object, equal to the
primitive int value represented by this
Integer object.

hashCode
public static int hashCode (int value)
Returns a hash code for a int
value; compatible with
Integer.hashCode()
.
Parameters  

value 
int : the value to hash 
Returns  

int 
a hash code value for a int value.

highestOneBit
public static int highestOneBit (int i)
Returns an int
value with at most a single onebit, in the
position of the highestorder ("leftmost") onebit in the specified
int
value. Returns zero if the specified value has no
onebits in its two's complement binary representation, that is, if it
is equal to zero.
Parameters  

i 
int : the value whose highest one bit is to be computed 
Returns  

int 
an int value with a single onebit, in the position
of the highestorder onebit in the specified value, or zero if
the specified value is itself equal to zero. 
intValue
public int intValue ()
Returns the value of this Integer
as an
int
.
Returns  

int 
the numeric value represented by this object after conversion
to type int .

longValue
public long longValue ()
Returns the value of this Integer
as a long
after a widening primitive conversion.
Returns  

long 
the numeric value represented by this object after conversion
to type long .

See also:
lowestOneBit
public static int lowestOneBit (int i)
Returns an int
value with at most a single onebit, in the
position of the lowestorder ("rightmost") onebit in the specified
int
value. Returns zero if the specified value has no
onebits in its two's complement binary representation, that is, if it
is equal to zero.
Parameters  

i 
int : the value whose lowest one bit is to be computed 
Returns  

int 
an int value with a single onebit, in the position
of the lowestorder onebit in the specified value, or zero if
the specified value is itself equal to zero. 
max
public static int max (int a, int b)
Returns the greater of two int
values
as if by calling Math.max
.
Parameters  

a 
int : the first operand 
b 
int : the second operand 
Returns  

int 
the greater of a and b 
See also:
min
public static int min (int a, int b)
Returns the smaller of two int
values
as if by calling Math.min
.
Parameters  

a 
int : the first operand 
b 
int : the second operand 
Returns  

int 
the smaller of a and b 
See also:
numberOfLeadingZeros
public static int numberOfLeadingZeros (int i)
Returns the number of zero bits preceding the highestorder
("leftmost") onebit in the two's complement binary representation
of the specified int
value. Returns 32 if the
specified value has no onebits in its two's complement representation,
in other words if it is equal to zero.
Note that this method is closely related to the logarithm base 2.
For all positive int
values x:
 floor(log_{2}(x)) =
31  numberOfLeadingZeros(x)
 ceil(log_{2}(x)) =
32  numberOfLeadingZeros(x  1)
Parameters  

i 
int : the value whose number of leading zeros is to be computed 
Returns  

int 
the number of zero bits preceding the highestorder
("leftmost") onebit in the two's complement binary representation
of the specified int value, or 32 if the value
is equal to zero. 
numberOfTrailingZeros
public static int numberOfTrailingZeros (int i)
Returns the number of zero bits following the lowestorder ("rightmost")
onebit in the two's complement binary representation of the specified
int
value. Returns 32 if the specified value has no
onebits in its two's complement representation, in other words if it is
equal to zero.
Parameters  

i 
int : the value whose number of trailing zeros is to be computed 
Returns  

int 
the number of zero bits following the lowestorder ("rightmost")
onebit in the two's complement binary representation of the
specified int value, or 32 if the value is equal
to zero. 
parseInt
public static int parseInt (String s, int radix)
Parses the string argument as a signed integer 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 integer value is returned.
An exception of type NumberFormatException
is
thrown if any of the following situations occurs:
 The first argument is
null
or is a string of length zero.  The radix is either smaller than
Character.MIN_RADIX
or larger thanCharacter.MAX_RADIX
.  Any character of the string is not a digit of the specified
radix, except that the first character may be a minus sign
''
('\u002D'
) or plus sign'+'
('\u002B'
) provided that the string is longer than length 1.  The value represented by the string is not a value of type
int
.
Examples:
parseInt("0", 10) returns 0 parseInt("473", 10) returns 473 parseInt("+42", 10) returns 42 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
Parameters  

s 
String : the String containing the integer
representation to be parsed 
radix 
int : the radix to be used while parsing s . 
Returns  

int 
the integer represented by the string argument in the specified radix. 
Throws  

NumberFormatException 
if the String
does not contain a parsable int .

parseInt
public static int parseInt (String s)
Parses the string argument as a signed decimal integer. 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 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.
Parameters  

s 
String : a String containing the int
representation to be parsed 
Returns  

int 
the integer value represented by the argument in decimal. 
Throws  

NumberFormatException 
if the string does not contain a parsable integer. 
parseUnsignedInt
public static int parseUnsignedInt (String s)
Parses the string argument as an unsigned decimal integer. The
characters in the string must all be decimal digits, except
that the first character may be an an ASCII plus sign '+'
('\u002B'
). The resulting integer value
is returned, exactly as if the argument and the radix 10 were
given as arguments to the parseUnsignedInt(java.lang.String, int)
method.
Parameters  

s 
String : a String containing the unsigned int
representation to be parsed 
Returns  

int 
the unsigned integer value represented by the argument in decimal. 
Throws  

NumberFormatException 
if the string does not contain a parsable unsigned integer. 
parseUnsignedInt
public static int parseUnsignedInt (String s, int radix)
Parses the string argument as an unsigned integer in the radix
specified by the second argument. An unsigned integer maps the
values usually associated with negative numbers to positive
numbers larger than MAX_VALUE
.
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 plus
sign '+'
('\u002B'
). The resulting
integer value is returned.
An exception of type NumberFormatException
is
thrown if any of the following situations occurs:
 The first argument is
null
or is a string of length zero.  The radix is either smaller than
Character.MIN_RADIX
or larger thanCharacter.MAX_RADIX
.  Any character of the string is not a digit of the specified
radix, except that the first character may be a plus sign
'+'
('\u002B'
) provided that the string is longer than length 1.  The value represented by the string is larger than the
largest unsigned
int
, 2^{32}1.
Parameters  

s 
String : the String containing the unsigned integer
representation to be parsed 
radix 
int : the radix to be used while parsing s . 
Returns  

int 
the integer represented by the string argument in the specified radix. 
Throws  

NumberFormatException 
if the String
does not contain a parsable int . 
remainderUnsigned
public static int remainderUnsigned (int dividend, int divisor)
Returns the unsigned remainder from dividing the first argument by the second where each argument and the result is interpreted as an unsigned value.
Parameters  

dividend 
int : the value to be divided 
divisor 
int : the value doing the dividing 
Returns  

int 
the unsigned remainder of the first argument divided by the second argument 
See also:
reverse
public static int reverse (int i)
Returns the value obtained by reversing the order of the bits in the
two's complement binary representation of the specified int
value.
Parameters  

i 
int : the value to be reversed 
Returns  

int 
the value obtained by reversing order of the bits in the
specified int value. 
reverseBytes
public static int reverseBytes (int i)
Returns the value obtained by reversing the order of the bytes in the
two's complement representation of the specified int
value.
Parameters  

i 
int : the value whose bytes are to be reversed 
Returns  

int 
the value obtained by reversing the bytes in the specified
int value. 
rotateLeft
public static int rotateLeft (int i, int distance)
Returns the value obtained by rotating the two's complement binary
representation of the specified int
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 32 is a
noop, so all but the last five bits of the rotation distance can be
ignored, even if the distance is negative: rotateLeft(val,
distance) == rotateLeft(val, distance & 0x1F)
.
Parameters  

i 
int : the value whose bits are to be rotated left 
distance 
int : the number of bit positions to rotate left 
Returns  

int 
the value obtained by rotating the two's complement binary
representation of the specified int value left by the
specified number of bits. 
rotateRight
public static int rotateRight (int i, int distance)
Returns the value obtained by rotating the two's complement binary
representation of the specified int
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 32 is a
noop, so all but the last five bits of the rotation distance can be
ignored, even if the distance is negative: rotateRight(val,
distance) == rotateRight(val, distance & 0x1F)
.
Parameters  

i 
int : the value whose bits are to be rotated right 
distance 
int : the number of bit positions to rotate right 
Returns  

int 
the value obtained by rotating the two's complement binary
representation of the specified int value right by the
specified number of bits. 
shortValue
public short shortValue ()
Returns the value of this Integer
as a short
after a narrowing primitive conversion.
Returns  

short 
the numeric value represented by this object after conversion
to type short . 
signum
public static int signum (int i)
Returns the signum function of the specified int
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.)
Parameters  

i 
int : the value whose signum is to be computed 
Returns  

int 
the signum function of the specified int value. 
sum
public static int sum (int a, int b)
Adds two integers together as per the + operator.
Parameters  

a 
int : the first operand 
b 
int : the second operand 
Returns  

int 
the sum of a and b 
See also:
toBinaryString
public static String toBinaryString (int i)
Returns a string representation of the integer argument as an unsigned integer in base 2.
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.
The value of the argument can be recovered from the returned
string s
by calling Integer.parseUnsignedInt(s, 2)
.
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.
Parameters  

i 
int : an integer to be converted to a string. 
Returns  

String 
the string representation of the unsigned integer value represented by the argument in binary (base 2). 
toHexString
public static String toHexString (int i)
Returns a string representation of the integer argument as an unsigned integer in base 16.
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.
The value of the argument can be recovered from the returned
string s
by calling Integer.parseUnsignedInt(s, 16)
.
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:
Integer.toHexString(n).toUpperCase()
Parameters  

i 
int : an integer to be converted to a string. 
Returns  

String 
the string representation of the unsigned integer value represented by the argument in hexadecimal (base 16). 
toOctalString
public static String toOctalString (int i)
Returns a string representation of the integer argument as an unsigned integer in base 8.
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.
The value of the argument can be recovered from the returned
string s
by calling Integer.parseUnsignedInt(s, 8)
.
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:
01234567
These are the characters '\u0030'
through
'\u0037'
.
Parameters  

i 
int : an integer to be converted to a string. 
Returns  

String 
the string representation of the unsigned integer value represented by the argument in octal (base 8). 
toString
public String toString ()
Returns a String
object representing this
Integer
's value. The value is converted to signed
decimal representation and returned as a string, exactly as if
the integer value were given as an argument to the toString(int)
method.
Returns  

String 
a string representation of the value of this object in base 10. 
toString
public static String toString (int i)
Returns a String
object representing the
specified integer. The argument is converted to signed decimal
representation and returned as a string, exactly as if the
argument and radix 10 were given as arguments to the toString(int, int)
method.
Parameters  

i 
int : an integer to be converted. 
Returns  

String 
a string representation of the argument in base 10. 
toString
public static String toString (int i, int radix)
Returns a string representation of the first argument in the radix specified by the second argument.
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:
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:
Integer.toString(n, 16).toUpperCase()
Parameters  

i 
int : an integer to be converted to a string. 
radix 
int : the radix to use in the string representation. 
Returns  

String 
a string representation of the argument in the specified radix. 
See also:
toUnsignedLong
public static long toUnsignedLong (int x)
Converts the argument to a long
by an unsigned
conversion. In an unsigned conversion to a long
, the
highorder 32 bits of the long
are zero and the
loworder 32 bits are equal to the bits of the integer
argument.
Consequently, zero and positive int
values are mapped
to a numerically equal long
value and negative int
values are mapped to a long
value equal to the
input plus 2^{32}.
Parameters  

x 
int : the value to convert to an unsigned long 
Returns  

long 
the argument converted to long by an unsigned
conversion 
toUnsignedString
public static String toUnsignedString (int i)
Returns a string representation of the argument as an unsigned
decimal value.
The argument is converted to unsigned decimal representation
and returned as a string exactly as if the argument and radix
10 were given as arguments to the toUnsignedString(int, int)
method.
Parameters  

i 
int : an integer to be converted to an unsigned string. 
Returns  

String 
an unsigned string representation of the argument. 
See also:
toUnsignedString
public static String toUnsignedString (int i, int radix)
Returns a string representation of the first argument as an unsigned integer value in the radix specified by the second argument.
If the radix is smaller than Character.MIN_RADIX
or larger than Character.MAX_RADIX
, then the radix
10
is used instead.
Note that since the first argument is treated as an unsigned value, no leading sign character is printed.
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 behavior of radixes and the characters used as digits
are the same as toString
.
Parameters  

i 
int : an integer to be converted to an unsigned string. 
radix 
int : the radix to use in the string representation. 
Returns  

String 
an unsigned string representation of the argument in the specified radix. 
See also:
valueOf
public static Integer valueOf (String s)
Returns an Integer
object holding the
value of the specified String
. The argument is
interpreted as representing a signed decimal integer, exactly
as if the argument were given to the 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))
Parameters  

s 
String : the string to be parsed. 
Returns  

Integer 
an Integer object holding the value
represented by the string argument. 
Throws  

NumberFormatException 
if the string cannot be parsed as an integer. 
valueOf
public static Integer valueOf (String s, int radix)
Returns an Integer
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 integer in the radix
specified by the second argument, exactly as if the arguments
were given to the 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))
Parameters  

s 
String : the string to be parsed. 
radix 
int : the radix to be used in interpreting s 
Returns  

Integer 
an Integer object holding the value
represented by the string argument in the specified
radix. 
Throws  

NumberFormatException 
if the String
does not contain a parsable int .

valueOf
public static Integer valueOf (int i)
Returns an Integer
instance representing the specified
int
value. If a new Integer
instance is not
required, this method should generally be used in preference to
the constructor Integer(int)
, as this method is likely
to yield significantly better space and time performance by
caching frequently requested values.
This method will always cache values in the range 128 to 127,
inclusive, and may cache other values outside of this range.
Parameters  

i 
int : an int value. 
Returns  

Integer 
an Integer instance representing i . 
Annotations
Interfaces
Classes
 Boolean
 Byte
 Character
 Character.Subset
 Character.UnicodeBlock
 Class
 ClassLoader
 Compiler
 Double
 Enum
 Float
 InheritableThreadLocal
 Integer
 Long
 Math
 Number
 Object
 Package
 Process
 ProcessBuilder
 ProcessBuilder.Redirect
 Runtime
 RuntimePermission
 SecurityManager
 Short
 StackTraceElement
 StrictMath
 String
 StringBuffer
 StringBuilder
 System
 Thread
 ThreadGroup
 ThreadLocal
 Throwable
 Void
Enums
Exceptions
 ArithmeticException
 ArrayIndexOutOfBoundsException
 ArrayStoreException
 ClassCastException
 ClassNotFoundException
 CloneNotSupportedException
 EnumConstantNotPresentException
 Exception
 IllegalAccessException
 IllegalArgumentException
 IllegalMonitorStateException
 IllegalStateException
 IllegalThreadStateException
 IndexOutOfBoundsException
 InstantiationException
 InterruptedException
 NegativeArraySizeException
 NoSuchFieldException
 NoSuchMethodException
 NullPointerException
 NumberFormatException
 ReflectiveOperationException
 RuntimeException
 SecurityException
 StringIndexOutOfBoundsException
 TypeNotPresentException
 UnsupportedOperationException
Errors
 AbstractMethodError
 AssertionError
 BootstrapMethodError
 ClassCircularityError
 ClassFormatError
 Error
 ExceptionInInitializerError
 IllegalAccessError
 IncompatibleClassChangeError
 InstantiationError
 InternalError
 LinkageError
 NoClassDefFoundError
 NoSuchFieldError
 NoSuchMethodError
 OutOfMemoryError
 StackOverflowError
 ThreadDeath
 UnknownError
 UnsatisfiedLinkError
 UnsupportedClassVersionError
 VerifyError
 VirtualMachineError