All Implemented Interfaces:

Serializable, Comparable<Integer>, Modified
```
public final class Integer
extends Number
implements Comparable<Integer>, Modified
```
The wrapper for the primitive type int.
Implementation note: The "bit twiddling" methods in this class use techniques described in Henry S. Warren, Jr.'s Hacker's Delight, (Addison Wesley, 2002) and Sean Anderson's Bit Twiddling Hacks.

Since:

1.0

See Also:

Long, Serialized Form

Field Summary

Fields
Modifier and Type	Field	Description
`static int`	`MAX_VALUE`	Constant for the maximum `int` value, 2³¹-1.
`static int`	`MIN_VALUE`	Constant for the minimum `int` value, -2³¹.
`static int`	`SIZE`	Constant for the number of bits needed to represent an `int` in two's complement form.

Constructor Summary

Constructors
Constructor	Description
`Integer(int value)`	Constructs a new `Integer` with the specified primitive integer value.
`Integer(String string)`	Constructs a new `Integer` from the specified string.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`static int`	`bitCount(int i)`	Counts the number of 1 bits in the specified integer; this is also referred to as population count.
`byte`	`byteValue()`	Returns this object's value as a byte.
`static int`	`compare(int lhs, int rhs)`	Compares two `int` values.
`int`	`compareTo(Integer object)`	Compares this object to the specified integer object to determine their relative order.
`static Integer`	`decode(String string)`	Parses the specified string and returns a `Integer` instance if the string can be decoded into an integer value.
`double`	`doubleValue()`	Returns this object's value as a double.
`boolean`	`equals(Object o)`	Compares this instance with the specified object and indicates if they are equal.
`float`	`floatValue()`	Returns this object's value as a float.
`int`	`hashCode()`	Returns an integer hash code for this object.
`static int`	`highestOneBit(int i)`	Determines the highest (leftmost) bit of the specified integer that is 1 and returns the bit mask value for that bit.
`int`	`intValue()`	Gets the primitive value of this int.
`long`	`longValue()`	Returns this object's value as a long.
`static int`	`lowestOneBit(int i)`	Determines the lowest (rightmost) bit of the specified integer that is 1 and returns the bit mask value for that bit.
`static int`	`numberOfLeadingZeros(int i)`	Determines the number of leading zeros in the specified integer prior to the `highest one bit`.
`static int`	`numberOfTrailingZeros(int i)`	Determines the number of trailing zeros in the specified integer after the `lowest one bit`.
`static int`	`parseInt(String string)`	Parses the specified string as a signed decimal integer value.
`static int`	`parseInt(String string, int radix)`	Parses the specified string as a signed integer value using the specified radix.
`static int`	`reverse(int i)`	Reverses the order of the bits of the specified integer.
`static int`	`reverseBytes(int i)`	Reverses the order of the bytes of the specified integer.
`static int`	`rotateLeft(int i, int distance)`	Rotates the bits of the specified integer to the left by the specified number of bits.
`static int`	`rotateRight(int i, int distance)`	Rotates the bits of the specified integer to the right by the specified number of bits.
`short`	`shortValue()`	Returns this object's value as a short.
`static int`	`signum(int i)`	Returns the value of the `signum` function for the specified integer.
`static String`	`toBinaryString(int i)`	Converts the specified integer into its binary string representation.
`static int`	`toCharArray(char[] string, int off, int val)`	Converts `integer` to a char array.
`static String`	`toHexString(int i)`	Converts the specified integer into its hexadecimal string representation.
`String`	`toString()`	Returns a string containing a concise, human-readable description of this object.
`static String`	`toString(int i)`	Converts the specified integer into its decimal string representation.
`static Integer`	`valueOf(int i)`	Returns a `Integer` instance for the specified integer value.
`static Integer`	`valueOf(String string)`	Parses the specified string as a signed decimal integer value.
`static Integer`	`valueOf(String string, int radix)`	Parses the specified string as a signed integer value using the specified radix.

Methods inherited from class java.lang.Object
getClass

- Field Detail
  - MAX_VALUE
```
public static final int MAX_VALUE
```
    Constant for the maximum int value, 2³¹-1.
    
    See Also:
    
    Constant Field Values
  - MIN_VALUE
```
public static final int MIN_VALUE
```
    Constant for the minimum int value, -2³¹.
    
    See Also:
    
    Constant Field Values
  - SIZE
```
public static final int SIZE
```
    Constant for the number of bits needed to represent an int in two's complement form.
    
    Since:
    
    1.5
    
    See Also:
    
    Constant Field Values
- Constructor Detail
  - Integer
```
public Integer(int value)
```
    Constructs a new Integer with the specified primitive integer value.
    
    Parameters:
    
    value - the primitive integer value to store in the new instance.
  - Integer
```
public Integer(String string)
        throws NumberFormatException
```
    Constructs a new Integer from the specified string.
    
    Parameters:
    
    string - the string representation of an integer value.
    
    Throws:
    
    NumberFormatException - if string cannot be parsed as an integer value.
    
    See Also:
    
    parseInt(String)
- Method Detail
  - byteValue
```
public byte byteValue()
```
    Description copied from class: Number
    
    Returns this object's value as a byte. Might involve rounding and/or truncating the value, so it fits into a byte.
    
    Overrides:
    
    byteValue in class Number
    
    Returns:
    
    the primitive byte value of this object.
  - compareTo
```
public int compareTo(Integer object)
```
    Compares this object to the specified integer object to determine their relative order.
    
    Specified by:
    
    compareTo in interface Comparable<Integer>
    
    Parameters:
    
    object - the integer object to compare this object to.
    
    Returns:
    
    a negative value if the value of this integer is less than the value of object; 0 if the value of this integer and the value of object are equal; a positive value if the value of this integer is greater than the value of object.
    
    Since:
    
    1.2
    
    See Also:
    
    Comparable
  - compare
```
public static int compare(int lhs,
                          int rhs)
```
    Compares two int values.
    
    Parameters:
    
    lhs - First value.
    
    rhs - Second value.
    
    Returns:
    
    0 if lhs = rhs, less than 0 if lhs < rhs, and greater than 0 if lhs > rhs.
    
    Since:
    
    1.7
  - decode
```
public static Integer decode(String string)
                      throws NumberFormatException
```
    Parses the specified string and returns a Integer instance if the string can be decoded into an integer value. The string may be an optional minus sign "-" followed by a hexadecimal ("0x..." or "#..."), octal ("0..."), or decimal ("...") representation of an integer.
    
    Parameters:
    
    string - a string representation of an integer value.
    
    Returns:
    
    an Integer containing the value represented by string.
    
    Throws:
    
    NumberFormatException - if string cannot be parsed as an integer value.
  - doubleValue
```
public double doubleValue()
```
    Description copied from class: Number
    
    Returns this object's value as a double. Might involve rounding.
    
    Specified by:
    
    doubleValue in class Number
    
    Returns:
    
    the primitive double value of this object.
  - equals
```
public boolean equals(Object o)
```
    Compares this instance with the specified object and indicates if they are equal. In order to be equal, o must be an instance of Integer and have the same integer value as this object.
    
    Overrides:
    
    equals in class Object
    
    Parameters:
    
    o - the object to compare this integer with.
    
    Returns:
    
    true if the specified object is equal to this Integer; false otherwise.
    
    See Also:
    
    Object.hashCode()
  - floatValue
```
public float floatValue()
```
    Description copied from class: Number
    
    Returns this object's value as a float. Might involve rounding.
    
    Specified by:
    
    floatValue in class Number
    
    Returns:
    
    the primitive float value of this object.
  - hashCode
```
public int hashCode()
```
    Description copied from class: Object
    
    Returns an integer hash code for this object. By contract, any two objects for which Object.equals(java.lang.Object) returns true must return the same hash code value. This means that subclasses of Object usually override both methods or neither method.
    Note that hash values must not change over time unless information used in equals comparisons also changes.
    See Writing a correct hashCode method if you intend implementing your own hashCode method.
    
    Overrides:
    
    hashCode in class Object
    
    Returns:
    
    this object's hash code.
    
    See Also:
    
    Object.equals(java.lang.Object)
  - intValue
```
public int intValue()
```
    Gets the primitive value of this int.
    
    Specified by:
    
    intValue in class Number
    
    Returns:
    
    this object's primitive value.
  - longValue
```
public long longValue()
```
    Description copied from class: Number
    
    Returns this object's value as a long. Might involve rounding and/or truncating the value, so it fits into a long.
    
    Specified by:
    
    longValue in class Number
    
    Returns:
    
    the primitive long value of this object.
  - parseInt
```
public static int parseInt(String string)
                    throws NumberFormatException
```
    Parses the specified string as a signed decimal integer value. The ASCII character - ('-') is recognized as the minus sign.
    
    Parameters:
    
    string - the string representation of an integer value.
    
    Returns:
    
    the primitive integer value represented by string.
    
    Throws:
    
    NumberFormatException - if string cannot be parsed as an integer value.
  - parseInt
```
public static int parseInt(String string,
                           int radix)
                    throws NumberFormatException
```
    Parses the specified string as a signed integer value using the specified radix. The ASCII character - ('-') is recognized as the minus sign.
    
    Parameters:
    
    string - the string representation of an integer value.
    
    radix - the radix to use when parsing.
    
    Returns:
    
    the primitive integer value represented by string using radix.
    
    Throws:
    
    NumberFormatException - if string cannot be parsed as an integer value, or radix < Character.MIN_RADIX || radix > Character.MAX_RADIX.
  - shortValue
```
public short shortValue()
```
    Description copied from class: Number
    
    Returns this object's value as a short. Might involve rounding and/or truncating the value, so it fits into a short.
    
    Overrides:
    
    shortValue in class Number
    
    Returns:
    
    the primitive short value of this object.
  - toString
```
public String toString()
```
    Description copied from class: Object
    
    Returns a string containing a concise, human-readable description of this object. Subclasses are encouraged to override this method and provide an implementation that takes into account the object's type and data.
    
    Overrides:
    
    toString in class Object
    
    Returns:
    
    a printable representation of this object.
  - toString
```
public static String toString(int i)
```
    Converts the specified integer into its decimal string representation. The returned string is a concatenation of a minus sign if the number is negative and characters from '0' to '9'.
    
    Parameters:
    
    i - the integer to convert.
    
    Returns:
    
    the decimal string representation of i.
  - toCharArray
```
public static int toCharArray(char[] string,
                              int off,
                              int val)
```
    Converts integer to a char array. No new string object is created!
    
    Parameters:
    
    string - the char array who represents the string.
    
    off - the start position of the char array.
    
    val - the integer to convert.
    
    Returns:
    
    the length of the string
  - toHexString
```
public static String toHexString(int i)
```
    Converts the specified integer into its hexadecimal string representation. The returned string is a concatenation of characters from '0' to '9' and 'a' to 'f'.
    
    Parameters:
    
    i - the integer to convert.
    
    Returns:
    
    the hexadecimal string representation of i.
  - toBinaryString
```
public static String toBinaryString(int i)
```
    Converts the specified integer into its binary string representation. The returned string is a concatenation of '0' and '1' characters.
    
    Parameters:
    
    i - the integer to convert.
    
    Returns:
    
    the binary string representation of i.
  - valueOf
```
public static Integer valueOf(String string)
                       throws NumberFormatException
```
    Parses the specified string as a signed decimal integer value.
    
    Parameters:
    
    string - the string representation of an integer value.
    
    Returns:
    
    an Integer instance containing the integer value represented by string.
    
    Throws:
    
    NumberFormatException - if string cannot be parsed as an integer value.
    
    See Also:
    
    parseInt(String)
  - valueOf
```
public static Integer valueOf(String string,
                              int radix)
                       throws NumberFormatException
```
    Parses the specified string as a signed integer value using the specified radix.
    
    Parameters:
    
    string - the string representation of an integer value.
    
    radix - the radix to use when parsing.
    
    Returns:
    
    an Integer instance containing the integer value represented by string using radix.
    
    Throws:
    
    NumberFormatException - if string cannot be parsed as an integer value, or radix < Character.MIN_RADIX || radix > Character.MAX_RADIX.
    
    See Also:
    
    parseInt(String, int)
  - highestOneBit
```
public static int highestOneBit(int i)
```
    Determines the highest (leftmost) bit of the specified integer that is 1 and returns the bit mask value for that bit. This is also referred to as the Most Significant 1 Bit. Returns zero if the specified integer is zero.
    
    Parameters:
    
    i - the integer to examine.
    
    Returns:
    
    the bit mask indicating the highest 1 bit in i.
    
    Since:
    
    1.5
  - lowestOneBit
```
public static int lowestOneBit(int i)
```
    Determines the lowest (rightmost) bit of the specified integer that is 1 and returns the bit mask value for that bit. This is also referred to as the Least Significant 1 Bit. Returns zero if the specified integer is zero.
    
    Parameters:
    
    i - the integer to examine.
    
    Returns:
    
    the bit mask indicating the lowest 1 bit in i.
    
    Since:
    
    1.5
  - numberOfLeadingZeros
```
public static int numberOfLeadingZeros(int i)
```
    Determines the number of leading zeros in the specified integer prior to the highest one bit.
    
    Parameters:
    
    i - the integer to examine.
    
    Returns:
    
    the number of leading zeros in i.
    
    Since:
    
    1.5
  - numberOfTrailingZeros
```
public static int numberOfTrailingZeros(int i)
```
    Determines the number of trailing zeros in the specified integer after the lowest one bit.
    
    Parameters:
    
    i - the integer to examine.
    
    Returns:
    
    the number of trailing zeros in i.
    
    Since:
    
    1.5
  - bitCount
```
public static int bitCount(int i)
```
    Counts the number of 1 bits in the specified integer; this is also referred to as population count.
    
    Parameters:
    
    i - the integer to examine.
    
    Returns:
    
    the number of 1 bits in i.
    
    Since:
    
    1.5
  - rotateLeft
```
public static int rotateLeft(int i,
                             int distance)
```
    Rotates the bits of the specified integer to the left by the specified number of bits.
    
    Parameters:
    
    i - the integer value to rotate left.
    
    distance - the number of bits to rotate.
    
    Returns:
    
    the rotated value.
    
    Since:
    
    1.5
  - rotateRight
```
public static int rotateRight(int i,
                              int distance)
```
    Rotates the bits of the specified integer to the right by the specified number of bits.
    
    Parameters:
    
    i - the integer value to rotate right.
    
    distance - the number of bits to rotate.
    
    Returns:
    
    the rotated value.
    
    Since:
    
    1.5
  - reverseBytes
```
public static int reverseBytes(int i)
```
    Reverses the order of the bytes of the specified integer.
    
    Parameters:
    
    i - the integer value for which to reverse the byte order.
    
    Returns:
    
    the reversed value.
    
    Since:
    
    1.5
  - reverse
```
public static int reverse(int i)
```
    Reverses the order of the bits of the specified integer.
    
    Parameters:
    
    i - the integer value for which to reverse the bit order.
    
    Returns:
    
    the reversed value.
    
    Since:
    
    1.5
  - signum
```
public static int signum(int i)
```
    Returns the value of the signum function for the specified integer.
    
    Parameters:
    
    i - the integer value to check.
    
    Returns:
    
    -1 if i is negative, 1 if i is positive, 0 if i is zero.
    
    Since:
    
    1.5
  - valueOf
```
public static Integer valueOf(int i)
```
    Returns a Integer instance for the specified integer value.
    
    Parameters:
    
    i - the integer value to store in the instance.
    
    Returns:
    
    a Integer instance containing i.
    
    Since:
    
    1.5

Class Integer

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

MAX_VALUE

MIN_VALUE

SIZE

Constructor Detail

Integer

Integer

Method Detail

byteValue

compareTo

compare

decode

doubleValue

equals

floatValue

hashCode

intValue

longValue

parseInt

parseInt

shortValue

toString

toString

toCharArray

toHexString

toBinaryString

valueOf

valueOf

highestOneBit

lowestOneBit

numberOfLeadingZeros

numberOfTrailingZeros

bitCount

rotateLeft

rotateRight

reverseBytes

reverse

signum

valueOf