Integer

public final class Integer extends Number
implements Comparable<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).

Constant Summary

int	BYTES	The number of bytes used to represent a int value in two's complement binary form.
int	MAX_VALUE	A constant holding the maximum value an int can have, 2^31-1.
int	MIN_VALUE	A constant holding the minimum value an int can have, -2^31.
int	SIZE	The number of bits used to represent an int value in two's complement binary form.

Field Summary

public static final Class<Integer>

TYPE

The Class instance representing the primitive type int.

Public Constructor Summary

	Integer(int value) Constructs a newly allocated Integer object that represents the specified int value.
	Integer(String s) Constructs a newly allocated Integer object that represents the int value indicated by the String parameter.

Public Method Summary

static int	bitCount(int i) Returns the number of one-bits in the two's complement binary representation of the specified int value.
byte	byteValue() Returns the value of this Integer as a byte after a narrowing primitive conversion.
static int	compare(int x, int y) Compares two int values numerically.
int	compareTo(Integer anotherInteger) Compares two Integer objects numerically.
static int	compareUnsigned(int x, int y) Compares two int values numerically treating the values as unsigned.
static Integer	decode(String nm) Decodes a String into an Integer.
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 Integer as a double after a widening primitive conversion.
boolean	equals(Object obj) Compares this object to the specified object.
float	floatValue() Returns the value of this Integer as a float after a widening primitive conversion.
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 Integer.
static int	hashCode(int value) Returns a hash code for a int value; compatible with Integer.hashCode().
static int	highestOneBit(int i) Returns an int value with at most a single one-bit, in the position of the highest-order ("leftmost") one-bit in the specified int value.
int	intValue() Returns the value of this Integer as an int.
long	longValue() Returns the value of this Integer as a long after a widening primitive conversion.
static int	lowestOneBit(int i) Returns an int value with at most a single one-bit, in the position of the lowest-order ("rightmost") one-bit in the specified int value.
static int	max(int a, int b) Returns the greater of two int values as if by calling Math.max.
static int	min(int a, int b) Returns the smaller of two int values as if by calling Math.min.
static int	numberOfLeadingZeros(int i) Returns the number of zero bits preceding the highest-order ("leftmost") one-bit in the two's complement binary representation of the specified int value.
static int	numberOfTrailingZeros(int i) Returns the number of zero bits following the lowest-order ("rightmost") one-bit in the two's complement binary representation of the specified int value.
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 int value.
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.
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.
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.
short	shortValue() Returns the value of this Integer as a short after a narrowing primitive conversion.
static int	signum(int i) Returns the signum function of the specified int value.
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 String object representing this Integer's value.
static String	toString(int i) Returns a String object representing the specified integer.
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 long by an unsigned conversion.
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 Integer object holding the value of the specified String.
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.
static Integer	valueOf(int i) Returns an Integer instance representing the specified int value.

Inherited Method Summary

From class java.lang.Number

byte	byteValue() Returns the value of the specified number as a byte, which may involve rounding or truncation.
abstract double	doubleValue() Returns the value of the specified number as a double, which may involve rounding.
abstract float	floatValue() Returns the value of the specified number as a float, which may involve rounding.
abstract int	intValue() Returns the value of the specified number as an int, which may involve rounding or truncation.
abstract long	longValue() Returns the value of the specified number as a long, which may involve rounding or truncation.
short	shortValue() Returns the value of the specified number as a short, which may involve rounding or truncation.

From class java.lang.Object

Object	clone() Creates and returns a copy of this Object.
boolean	equals(Object obj) Compares this instance with the specified object and indicates if they are equal.
void	finalize() Invoked when the garbage collector has detected that this instance is no longer reachable.
final Class<?>	getClass() Returns the unique instance of Class that represents this object's class.
int	hashCode() Returns an integer hash code for this object.
final void	notify() Causes a thread which is waiting on this object's monitor (by means of calling one of the wait() methods) to be woken up.
final void	notifyAll() Causes all threads which are waiting on this object's monitor (by means of calling one of the wait() methods) to be woken up.
String	toString() Returns a string containing a concise, human-readable description of this object.
final void	wait(long timeout, int nanos) Causes the calling thread to wait until another thread calls the notify() or notifyAll() method of this object or until the specified timeout expires.
final void	wait(long timeout) Causes the calling thread to wait until another thread calls the notify() or notifyAll() method of this object or until the specified timeout expires.
final void	wait() Causes the calling thread to wait until another thread calls the notify() or notifyAll() method of this object.

From interface java.lang.Comparable

abstract int

compareTo(Integer o) Compares this object with the specified object for order.

Constants

public static final int BYTES

The number of bytes used to represent a int value in two's complement binary form.

Constant Value: 4

public static final int MAX_VALUE

A constant holding the maximum value an int can have, 2³¹-1.

Constant Value: 2147483647

public static final int MIN_VALUE

A constant holding the minimum value an int can have, -2³¹.

Constant Value: -2147483648

public static final int SIZE

The number of bits used to represent an int value in two's complement binary form.

Constant Value: 32

Fields

public static final Class<Integer> TYPE

The Class instance representing the primitive type int.

Public Constructors

public Integer (int value)

Constructs a newly allocated Integer object that represents the specified int value.

Parameters

value	the value to be represented by the Integer object.

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	the String to be converted to an Integer.

Throws

NumberFormatException	if the String does not contain a parsable integer.

See Also

• parseInt(java.lang.String, int)

Public Methods

public static int bitCount (int i)

Returns the number of one-bits in the two's complement binary representation of the specified int value. This function is sometimes referred to as the population count.

Parameters

i	the value whose bits are to be counted

Returns

• the number of one-bits in the two's complement binary representation of the specified int value.

public byte byteValue ()

Returns the value of this Integer as a byte after a narrowing primitive conversion.

Returns

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

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	the first int to compare
y	the second int to compare

Returns

• the value 0 if x == y; a value less than 0 if x < y; and a value greater than 0 if x > y

public int compareTo (Integer anotherInteger)

Compares two Integer objects numerically.

Parameters

anotherInteger	the Integer to be compared.

Returns

• 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).

public static int compareUnsigned (int x, int y)

Compares two int values numerically treating the values as unsigned.

Parameters

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

Returns

• 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

public static Integer decode (String nm)

Decodes a String into an Integer. Accepts decimal, hexadecimal, and octal numbers given by the following grammar:

DecodableString:

Sign_opt DecimalNumeral

Sign_opt 0x HexDigits

Sign_opt 0X HexDigits

Sign_opt # HexDigits

Sign_opt 0 OctalDigits

Sign:

-

+

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.

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	the String to decode.

Returns

• an Integer object holding the int value represented by nm

Throws

NumberFormatException	if the String does not contain a parsable integer.

See Also

• parseInt(java.lang.String, int)

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 bit-wise 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	the value to be divided
divisor	the value doing the dividing

Returns

• the unsigned quotient of the first argument divided by the second argument

See Also

• remainderUnsigned(int, int)

public double doubleValue ()

Returns the value of this Integer as a double after a widening primitive conversion.

Returns

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

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	the object to compare with.

Returns

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

public float floatValue ()

Returns the value of this Integer as a float after a widening primitive conversion.

Returns

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

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 method valueOf(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 method valueOf(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	property name.
val	default value.

Returns

• the Integer value of the property.

Throws

SecurityException	for the same reasons as System.getProperty

See Also

• System.getProperty(java.lang.String)
• System.getProperty(java.lang.String, java.lang.String)

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	property name.

Returns

• the Integer value of the property.

Throws

SecurityException	for the same reasons as System.getProperty

See Also

• System.getProperty(java.lang.String)
• System.getProperty(java.lang.String, java.lang.String)

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:

 Integer result = getInteger(nm, null);
 return (result == null) ? new Integer(val) : result;
 

to avoid the unnecessary allocation of an Integer object when the default value is not needed.

Parameters

nm	property name.
val	default value.

Returns

• the Integer value of the property.

Throws

SecurityException	for the same reasons as System.getProperty

See Also

• System.getProperty(java.lang.String)
• System.getProperty(java.lang.String, java.lang.String)

public int hashCode ()

Returns a hash code for this Integer.

Returns

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

public static int hashCode (int value)

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

Parameters

value	the value to hash

Returns

• a hash code value for a int value.

public static int highestOneBit (int i)

Returns an int value with at most a single one-bit, in the position of the highest-order ("leftmost") one-bit in the specified int value. Returns zero if the specified value has no one-bits in its two's complement binary representation, that is, if it is equal to zero.

Parameters

i	the value whose highest one bit is to be computed

Returns

• an int value with a single one-bit, in the position of the highest-order one-bit in the specified value, or zero if the specified value is itself equal to zero.

public int intValue ()

Returns the value of this Integer as an int.

Returns

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

public long longValue ()

Returns the value of this Integer as a long after a widening primitive conversion.

Returns

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

See Also

• toUnsignedLong(int)

public static int lowestOneBit (int i)

Returns an int value with at most a single one-bit, in the position of the lowest-order ("rightmost") one-bit in the specified int value. Returns zero if the specified value has no one-bits in its two's complement binary representation, that is, if it is equal to zero.

Parameters

i	the value whose lowest one bit is to be computed

Returns

• an int value with a single one-bit, in the position of the lowest-order one-bit in the specified value, or zero if the specified value is itself equal to zero.

public static int max (int a, int b)

Returns the greater of two int values as if by calling Math.max.

Parameters

a	the first operand
b	the second operand

Returns

• the greater of a and b

See Also

• BinaryOperator

public static int min (int a, int b)

Returns the smaller of two int values as if by calling Math.min.

Parameters

a	the first operand
b	the second operand

Returns

• the smaller of a and b

See Also

• BinaryOperator

public static int numberOfLeadingZeros (int i)

Returns the number of zero bits preceding the highest-order ("leftmost") one-bit in the two's complement binary representation of the specified int value. Returns 32 if the specified value has no one-bits 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(log₂(x)) = 31 - numberOfLeadingZeros(x)
• ceil(log₂(x)) = 32 - numberOfLeadingZeros(x - 1)

Parameters

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

Returns

• the number of zero bits preceding the highest-order ("leftmost") one-bit in the two's complement binary representation of the specified int value, or 32 if the value is equal to zero.

public static int numberOfTrailingZeros (int i)

Returns the number of zero bits following the lowest-order ("rightmost") one-bit in the two's complement binary representation of the specified int value. Returns 32 if the specified value has no one-bits in its two's complement representation, in other words if it is equal to zero.

Parameters

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

Returns

• the number of zero bits following the lowest-order ("rightmost") one-bit in the two's complement binary representation of the specified int value, or 32 if the value is equal to zero.

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 than Character.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	the String containing the integer representation to be parsed
radix	the radix to be used while parsing s.

Returns

• the integer represented by the string argument in the specified radix.

Throws

NumberFormatException	if the String does not contain a parsable int.

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	a String containing the int representation to be parsed

Returns

• the integer value represented by the argument in decimal.

Throws

NumberFormatException	if the string does not contain a parsable integer.

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	a String containing the unsigned int representation to be parsed

Returns

• the unsigned integer value represented by the argument in decimal.

Throws

NumberFormatException	if the string does not contain a parsable unsigned integer.

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 than Character.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, 2³²-1.

Parameters

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

Returns

• the integer represented by the string argument in the specified radix.

Throws

NumberFormatException	if the String does not contain a parsable int.

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	the value to be divided
divisor	the value doing the dividing

Returns

• the unsigned remainder of the first argument divided by the second argument

See Also

• divideUnsigned(int, int)

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	the value to be reversed

Returns

• the value obtained by reversing order of the bits in the specified int value.

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	the value whose bytes are to be reversed

Returns

• the value obtained by reversing the bytes in the specified int value.

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 high-order, side reenter on the right, or low-order.)

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 no-op, 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	the value whose bits are to be rotated left
distance	the number of bit positions to rotate left

Returns

• the value obtained by rotating the two's complement binary representation of the specified int value left by the specified number of bits.

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 low-order, side reenter on the left, or high-order.)

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 no-op, 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	the value whose bits are to be rotated right
distance	the number of bit positions to rotate right

Returns

• the value obtained by rotating the two's complement binary representation of the specified int value right by the specified number of bits.

public short shortValue ()

Returns the value of this Integer as a short after a narrowing primitive conversion.

Returns

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

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	the value whose signum is to be computed

Returns

• the signum function of the specified int value.

public static int sum (int a, int b)

Adds two integers together as per the + operator.

Parameters

a	the first operand
b	the second operand

Returns

• the sum of a and b

See Also

• BinaryOperator

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 2³² 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 0s.

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	an integer to be converted to a string.

Returns

• the string representation of the unsigned integer value represented by the argument in binary (base 2).

See Also

• parseUnsignedInt(String, int)
• toUnsignedString(int, int)

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 2³² 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 0s.

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	an integer to be converted to a string.

Returns

• the string representation of the unsigned integer value represented by the argument in hexadecimal (base 16).

See Also

• parseUnsignedInt(String, int)
• toUnsignedString(int, int)

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 2³² 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 0s.

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	an integer to be converted to a string.

Returns

• the string representation of the unsigned integer value represented by the argument in octal (base 8).

See Also

• parseUnsignedInt(String, int)
• toUnsignedString(int, int)

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

• a string representation of the value of this object in base 10.

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	an integer to be converted.

Returns

• a string representation of the argument in base 10.

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 radix-N 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	an integer to be converted to a string.
radix	the radix to use in the string representation.

Returns

• a string representation of the argument in the specified radix.

See Also

• Character.MAX_RADIX
• Character.MIN_RADIX

public static long toUnsignedLong (int x)

Converts the argument to a long by an unsigned conversion. In an unsigned conversion to a long, the high-order 32 bits of the long are zero and the low-order 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 2³².

Parameters

x	the value to convert to an unsigned long

Returns

• the argument converted to long by an unsigned conversion

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	an integer to be converted to an unsigned string.

Returns

• an unsigned string representation of the argument.

See Also

• toUnsignedString(int, int)

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	an integer to be converted to an unsigned string.
radix	the radix to use in the string representation.

Returns

• an unsigned string representation of the argument in the specified radix.

See Also

• toString(int, int)

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	the string to be parsed.

Returns

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

Throws

NumberFormatException	if the string cannot be parsed as an integer.

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	the string to be parsed.
radix	the radix to be used in interpreting s

Returns

• 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.

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	an int value.

Returns

• an Integer instance representing i.