Long (Java SE 26 & JDK 26)
Description: declaration: module: java.base, package: java.lang, class: Long
Keywords: java.lang.Long class

# Class Long

java.lang.Object
java.lang.Number
java.lang.Long

All Implemented Interfaces:
  `Serializable, Comparable<Long>, Constable, ConstantDesc`

public final class Long extends Number implements Comparable<Long>, Constable, ConstantDesc
The `Long` class is the wrapper class for values of the primitive type `long`. An object of type `Long` contains a single field whose type is `long`.

In addition, this class provides several methods for converting a `long` to a `String` and a `String` to a `long`, as well as other constants and methods useful when dealing with a `long`.

This is a value-based class; programmers should treat instances that are equal as interchangeable and should not use instances for synchronization, or unpredictable behavior may occur. For example, in a future release, synchronization may fail.

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) and Hacker's Delight, Second Edition, (Pearson Education, 2013).

Since:
  1.0
See Also:
  - Serialized Form

- ## Field Summary

  Fields
  Modifier and Type
  Field
  Description
  `static final int`
  `BYTES`
  The number of bytes used to represent a `long` value in two's complement binary form.
  `static final long`
  `MAX_VALUE`
  A constant holding the maximum value a `long` can have, 263-1.
  `static final long`
  `MIN_VALUE`
  A constant holding the minimum value a `long` can have, -263.
  `static final int`
  `SIZE`
  The number of bits used to represent a `long` value in two's complement binary form.
  `static final Class<Long>`
  `TYPE`
  The `Class` instance representing the primitive type `long`.

- ## Constructor Summary

  Constructors
  Constructor
  Description
  `Long(long value)`
  Deprecated.
  It is rarely appropriate to use this constructor.
  `Long(String s)`
  Deprecated.
  It is rarely appropriate to use this constructor.

- ## Method Summary

  Modifier and Type
  Method
  Description
  `static int`
  `bitCount(long i)`
  Returns the number of one-bits in the two's complement binary representation of the specified `long` value.
  `byte`
  `byteValue()`
  Returns the value of this `Long` as a `byte` after a narrowing primitive conversion.
  `static int`
  `compare(long x, long y)`
  Compares two `long` values numerically.
  `int`
  `compareTo(Long anotherLong)`
  Compares two `Long` objects numerically.
  `static int`
  `compareUnsigned(long x, long y)`
  Compares two `long` values numerically treating the values as unsigned.
  `static long`
  `compress(long i, long mask)`
  Returns the value obtained by compressing the bits of the specified `long` value, `i`, in accordance with the specified bit mask.
  `static Long`
  `decode(String nm)`
  Decodes a `String` into a `Long`.
  `Optional<Long>`
  `describeConstable()`
  Returns an `Optional` containing the nominal descriptor for this instance, which is the instance itself.
  `static long`
  `divideUnsigned(long dividend, long 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 `Long` as a `double` after a widening primitive conversion.
  `boolean`
  `equals(Object obj)`
  Compares this object to the specified object.
  `static long`
  `expand(long i, long mask)`
  Returns the value obtained by expanding the bits of the specified `long` value, `i`, in accordance with the specified bit mask.
  `float`
  `floatValue()`
  Returns the value of this `Long` as a `float` after a widening primitive conversion.
  `static Long`
  `getLong(String nm)`
  Determines the `long` value of the system property with the specified name.
  `static Long`
  `getLong(String nm, long val)`
  Determines the `long` value of the system property with the specified name.
  `static Long`
  `getLong(String nm, Long val)`
  Returns the `long` value of the system property with the specified name.
  `int`
  `hashCode()`
  Returns a hash code for this `Long`.
  `static int`
  `hashCode(long value)`
  Returns a hash code for a `long` value; compatible with `Long.hashCode()`.
  `static long`
  `highestOneBit(long i)`
  Returns a `long` value with at most a single one-bit, in the position of the highest-order ("leftmost") one-bit in the specified `long` value.
  `int`
  `intValue()`
  Returns the value of this `Long` as an `int` after a narrowing primitive conversion.
  `long`
  `longValue()`
  Returns the value of this `Long` as a `long` value.
  `static long`
  `lowestOneBit(long i)`
  Returns a `long` value with at most a single one-bit, in the position of the lowest-order ("rightmost") one-bit in the specified `long` value.
  `static long`
  `max(long a, long b)`
  Returns the greater of two `long` values as if by calling `Math.max`.
  `static long`
  `min(long a, long b)`
  Returns the smaller of two `long` values as if by calling `Math.min`.
  `static int`
  `numberOfLeadingZeros(long i)`
  Returns the number of zero bits preceding the highest-order ("leftmost") one-bit in the two's complement binary representation of the specified `long` value.
  `static int`
  `numberOfTrailingZeros(long i)`
  Returns the number of zero bits following the lowest-order ("rightmost") one-bit in the two's complement binary representation of the specified `long` value.
  `static long`
  `parseLong(CharSequence s, int beginIndex, int endIndex, int radix)`
  Parses the `CharSequence` argument as a signed `long` in the specified `radix`, beginning at the specified `beginIndex` and extending to `endIndex - 1`.
  `static long`
  `parseLong(String s)`
  Parses the string argument as a signed decimal `long`.
  `static long`
  `parseLong(String s, int radix)`
  Parses the string argument as a signed `long` in the radix specified by the second argument.
  `static long`
  `parseUnsignedLong(CharSequence s, int beginIndex, int endIndex, int radix)`
  Parses the `CharSequence` argument as an unsigned `long` in the specified `radix`, beginning at the specified `beginIndex` and extending to `endIndex - 1`.
  `static long`
  `parseUnsignedLong(String s)`
  Parses the string argument as an unsigned decimal `long`.
  `static long`
  `parseUnsignedLong(String s, int radix)`
  Parses the string argument as an unsigned `long` in the radix specified by the second argument.
  `static long`
  `remainderUnsigned(long dividend, long 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.
  `Long`
  `resolveConstantDesc(MethodHandles.Lookup lookup)`
  Resolves this instance as a `ConstantDesc`, the result of which is the instance itself.
  `static long`
  `reverse(long i)`
  Returns the value obtained by reversing the order of the bits in the two's complement binary representation of the specified `long` value.
  `static long`
  `reverseBytes(long i)`
  Returns the value obtained by reversing the order of the bytes in the two's complement representation of the specified `long` value.
  `static long`
  `rotateLeft(long i, int distance)`
  Returns the value obtained by rotating the two's complement binary representation of the specified `long` value left by the specified number of bits.
  `static long`
  `rotateRight(long i, int distance)`
  Returns the value obtained by rotating the two's complement binary representation of the specified `long` value right by the specified number of bits.
  `short`
  `shortValue()`
  Returns the value of this `Long` as a `short` after a narrowing primitive conversion.
  `static int`
  `signum(long i)`
  Returns the signum function of the specified `long` value.
  `static long`
  `sum(long a, long b)`
  Adds two `long` values together as per the + operator.
  `static String`
  `toBinaryString(long i)`
  Returns a string representation of the `long` argument as an unsigned integer in base 2.
  `static String`
  `toHexString(long i)`
  Returns a string representation of the `long` argument as an unsigned integer in base 16.
  `static String`
  `toOctalString(long i)`
  Returns a string representation of the `long` argument as an unsigned integer in base 8.
  `String`
  `toString()`
  Returns a `String` object representing this `Long`'s value.
  `static String`
  `toString(long i)`
  Returns a `String` object representing the specified `long`.
  `static String`
  `toString(long i, int radix)`
  Returns a string representation of the first argument in the radix specified by the second argument.
  `static String`
  `toUnsignedString(long i)`
  Returns a string representation of the argument as an unsigned decimal value.
  `static String`
  `toUnsignedString(long 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 Long`
  `valueOf(long l)`
  Returns a `Long` instance representing the specified `long` value.
  `static Long`
  `valueOf(String s)`
  Returns a `Long` object holding the value of the specified `String`.
  `static Long`
  `valueOf(String s, int radix)`
  Returns a `Long` object holding the value extracted from the specified `String` when parsed with the radix given by the second argument.

  ### Methods declared in class Object

  `clone, finalize, getClass, notify, notifyAll, wait, wait, wait`
  Modifier and Type
  Method
  Description
  `protected Object`
  `clone()`
  Creates and returns a copy of this object.
  `protected void`
  `finalize()`
  Deprecated, for removal: This API element is subject to removal in a future version.
  Finalization is deprecated and subject to removal in a future release.
  `final Class<?>`
  `getClass()`
  Returns the runtime class of this `Object`.
  `final void`
  `notify()`
  Wakes up a single thread that is waiting on this object's monitor.
  `final void`
  `notifyAll()`
  Wakes up all threads that are waiting on this object's monitor.
  `final void`
  `wait()`
  Causes the current thread to wait until it is awakened, typically by being notified or interrupted.
  `final void`
  `wait(long timeoutMillis)`
  Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.
  `final void`
  `wait(long timeoutMillis, int nanos)`
  Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.

- ## Field Details

  - ### MIN_VALUE

    @Native public static final long MIN_VALUE
    A constant holding the minimum value a `long` can have, -263.
    See Also:
      - Constant Field Values

  - ### MAX_VALUE

    @Native public static final long MAX_VALUE
    A constant holding the maximum value a `long` can have, 263-1.
    See Also:
      - Constant Field Values

  - ### TYPE

    public static final Class<Long> TYPE
    The `Class` instance representing the primitive type `long`.
    Since:
      1.1

  - ### SIZE

    @Native public static final int SIZE
    The number of bits used to represent a `long` value in two's complement binary form.
    Since:
      1.5
    See Also:
      - Constant Field Values

  - ### BYTES

    public static final int BYTES
    The number of bytes used to represent a `long` value in two's complement binary form.
    Since:
      1.8
    See Also:
      - Constant Field Values

- ## Constructor Details

  - ### Long

    @Deprecated(since="9") public Long(long value)
    Deprecated.
    It is rarely appropriate to use this constructor. The static factory `valueOf(long)` is generally a better choice, as it is likely to yield significantly better space and time performance.
    Constructs a newly allocated `Long` object that represents the specified `long` argument.
    Parameters:
      `value` - the value to be represented by the `Long` object.

  - ### Long

    @Deprecated(since="9") public Long(String s) throws NumberFormatException
    Deprecated.
    It is rarely appropriate to use this constructor. Use `parseLong(String)` to convert a string to a `long` primitive, or use `valueOf(String)` to convert a string to a `Long` object.
    Constructs a newly allocated `Long` object that represents the `long` value indicated by the `String` parameter. The string is converted to a `long` value in exactly the manner used by the `parseLong` method for radix 10.
    Parameters:
      `s` - the `String` to be converted to a `Long`.
    Throws:
      `NumberFormatException` - if the `String` does not contain a parsable `long`.

- ## Method Details

  - ### toString

    public static String toString(long 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 sign `'-'` (`'\u002d'`). If the first argument is not negative, no sign character appears in the result.

    The remaining characters of the result represent the magnitude of the first argument. If the magnitude is zero, it is represented by a single zero character `'0'` (`'\u0030'`); otherwise, the first character of the representation of the magnitude will not be the zero character. The following ASCII characters are used as digits:

    > `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:

    > `Long.toString(n, 16).toUpperCase()`

    Parameters:
      `i` - a `long` 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`

  - ### toUnsignedString

    public static String toUnsignedString(long 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.
    Since:
      1.8
    See Also:
      - `toString(long, int)`

  - ### toHexString

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

    The unsigned `long` value is the argument plus 264 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 `Long.parseUnsignedLong(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:

    > `Long.toHexString(n).toUpperCase()`

    API Note:
      The `HexFormat` class provides formatting and parsing of byte arrays and primitives to return a string or adding to an `Appendable`. `HexFormat` formats and parses uppercase or lowercase hexadecimal characters, with leading zeros and for byte arrays includes for each byte a delimiter, prefix, and suffix.
    Parameters:
      `i` - a `long` to be converted to a string.
    Returns:
      the string representation of the unsigned `long` value represented by the argument in hexadecimal (base 16).
    Since:
      1.0.2
    See Also:
      - `HexFormat`
      - `parseUnsignedLong(String, int)`
      - `toUnsignedString(long, int)`

  - ### toOctalString

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

    The unsigned `long` value is the argument plus 264 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 `Long.parseUnsignedLong(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` - a `long` to be converted to a string.
    Returns:
      the string representation of the unsigned `long` value represented by the argument in octal (base 8).
    Since:
      1.0.2
    See Also:
      - `parseUnsignedLong(String, int)`
      - `toUnsignedString(long, int)`

  - ### toBinaryString

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

    The unsigned `long` value is the argument plus 264 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 `Long.parseUnsignedLong(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` - a `long` to be converted to a string.
    Returns:
      the string representation of the unsigned `long` value represented by the argument in binary (base 2).
    Since:
      1.0.2
    See Also:
      - `parseUnsignedLong(String, int)`
      - `toUnsignedString(long, int)`

  - ### toString

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

  - ### toUnsignedString

    public static String toUnsignedString(long 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(long, int)` method.
    Parameters:
      `i` - an integer to be converted to an unsigned string.
    Returns:
      an unsigned string representation of the argument.
    Since:
      1.8
    See Also:
      - `toUnsignedString(long, int)`

  - ### parseLong

    public static long parseLong(String s, int radix) throws NumberFormatException
    Parses the string argument as a signed `long` in the radix specified by the second argument. The characters in the string must all be digits of the specified radix (as determined by whether `Character.digit(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 `long` value is returned.

    Note that neither the character `L` (`'\u004C'`) nor `l` (`'\u006C'`) is permitted to appear at the end of the string as a type indicator, as would be permitted in Java programming language source code - except that either `L` or `l` may appear as a digit for a radix greater than or equal to 22.

    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 `long`.

    Examples:

    >     parseLong("0", 10) returns 0L
    >     parseLong("473", 10) returns 473L
    >     parseLong("+42", 10) returns 42L
    >     parseLong("-0", 10) returns 0L
    >     parseLong("-FF", 16) returns -255L
    >     parseLong("1100110", 2) returns 102L
    >     parseLong("99", 8) throws a NumberFormatException
    >     parseLong("Hazelnut", 10) throws a NumberFormatException
    >     parseLong("Hazelnut", 36) returns 1356099454469L

    Parameters:
      `s` - the `String` containing the `long` representation to be parsed.
      `radix` - the radix to be used while parsing `s`.
    Returns:
      the `long` represented by the string argument in the specified radix.
    Throws:
      `NumberFormatException` - if the string does not contain a parsable `long`.

  - ### parseLong

    public static long parseLong(CharSequence s, int beginIndex, int endIndex, int radix) throws NumberFormatException
    Parses the `CharSequence` argument as a signed `long` in the specified `radix`, beginning at the specified `beginIndex` and extending to `endIndex - 1`.

    The method does not take steps to guard against the `CharSequence` being mutated while parsing.

    Parameters:
      `s` - the `CharSequence` containing the `long` representation to be parsed
      `beginIndex` - the beginning index, inclusive.
      `endIndex` - the ending index, exclusive.
      `radix` - the radix to be used while parsing `s`.
    Returns:
      the signed `long` represented by the subsequence in the specified radix.
    Throws:
      `NullPointerException` - if `s` is null.
      `IndexOutOfBoundsException` - if `beginIndex` is negative, or if `beginIndex` is greater than `endIndex` or if `endIndex` is greater than `s.length()`.
      `NumberFormatException` - if the `CharSequence` does not contain a parsable `long` in the specified `radix`, or if `radix` is either smaller than `Character.MIN_RADIX` or larger than `Character.MAX_RADIX`.
    Since:
      9

  - ### parseLong

    public static long parseLong(String s) throws NumberFormatException
    Parses the string argument as a signed decimal `long`. The characters in the string must all be decimal digits, except that the first character may be an ASCII minus sign `'-'` (`\u002D'`) to indicate a negative value or an ASCII plus sign `'+'` (`'\u002B'`) to indicate a positive value. The resulting `long` value is returned, exactly as if the argument and the radix `10` were given as arguments to the `parseLong(java.lang.String, int)` method.

    Note that neither the character `L` (`'\u004C'`) nor `l` (`'\u006C'`) is permitted to appear at the end of the string as a type indicator, as would be permitted in Java programming language source code.

    Parameters:
      `s` - a `String` containing the `long` representation to be parsed
    Returns:
      the `long` represented by the argument in decimal.
    Throws:
      `NumberFormatException` - if the string does not contain a parsable `long`.

  - ### parseUnsignedLong

    public static long parseUnsignedLong(String s, int radix) throws NumberFormatException
    Parses the string argument as an unsigned `long` 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 `long`, 264-1.
    Parameters:
      `s` - the `String` containing the unsigned integer representation to be parsed
      `radix` - the radix to be used while parsing `s`.
    Returns:
      the unsigned `long` represented by the string argument in the specified radix.
    Throws:
      `NumberFormatException` - if the `String` does not contain a parsable `long`.
    Since:
      1.8

  - ### parseUnsignedLong

    public static long parseUnsignedLong(CharSequence s, int beginIndex, int endIndex, int radix) throws NumberFormatException
    Parses the `CharSequence` argument as an unsigned `long` in the specified `radix`, beginning at the specified `beginIndex` and extending to `endIndex - 1`.

    The method does not take steps to guard against the `CharSequence` being mutated while parsing.

    Parameters:
      `s` - the `CharSequence` containing the unsigned `long` representation to be parsed
      `beginIndex` - the beginning index, inclusive.
      `endIndex` - the ending index, exclusive.
      `radix` - the radix to be used while parsing `s`.
    Returns:
      the unsigned `long` represented by the subsequence in the specified radix.
    Throws:
      `NullPointerException` - if `s` is null.
      `IndexOutOfBoundsException` - if `beginIndex` is negative, or if `beginIndex` is greater than `endIndex` or if `endIndex` is greater than `s.length()`.
      `NumberFormatException` - if the `CharSequence` does not contain a parsable unsigned `long` in the specified `radix`, or if `radix` is either smaller than `Character.MIN_RADIX` or larger than `Character.MAX_RADIX`.
    Since:
      9

  - ### parseUnsignedLong

    public static long parseUnsignedLong(String s) throws NumberFormatException
    Parses the string argument as an unsigned decimal `long`. The characters in the string must all be decimal digits, except that the first character may be 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 `parseUnsignedLong(java.lang.String, int)` method.
    Parameters:
      `s` - a `String` containing the unsigned `long` representation to be parsed
    Returns:
      the unsigned `long` value represented by the decimal string argument
    Throws:
      `NumberFormatException` - if the string does not contain a parsable unsigned integer.
    Since:
      1.8

  - ### valueOf

    public static Long valueOf(String s, int radix) throws NumberFormatException
    Returns a `Long` 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 `long` in the radix specified by the second argument, exactly as if the arguments were given to the `parseLong(java.lang.String, int)` method. The result is a `Long` object that represents the `long` value specified by the string.

    In other words, this method returns a `Long` object equal to the value of:

    > `Long.valueOf(Long.parseLong(s, radix))`

    Parameters:
      `s` - the string to be parsed
      `radix` - the radix to be used in interpreting `s`
    Returns:
      a `Long` object holding the value represented by the string argument in the specified radix.
    Throws:
      `NumberFormatException` - If the `String` does not contain a parsable `long`.

  - ### valueOf

    public static Long valueOf(String s) throws NumberFormatException
    Returns a `Long` object holding the value of the specified `String`. The argument is interpreted as representing a signed decimal `long`, exactly as if the argument were given to the `parseLong(java.lang.String)` method. The result is a `Long` object that represents the integer value specified by the string.

    In other words, this method returns a `Long` object equal to the value of:

    > `Long.valueOf(Long.parseLong(s))`

    Parameters:
      `s` - the string to be parsed.
    Returns:
      a `Long` object holding the value represented by the string argument.
    Throws:
      `NumberFormatException` - If the string cannot be parsed as a `long`.

  - ### valueOf

    public static Long valueOf(long l)
    Returns a `Long` instance representing the specified `long` value. If a new `Long` instance is not required, this method should generally be used in preference to the constructor `Long(long)`, 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:
      `l` - a long value.
    Returns:
      a `Long` instance representing `l`.
    Since:
      1.5

  - ### decode

    public static Long decode(String nm) throws NumberFormatException
    Decodes a `String` into a `Long`. Accepts decimal, hexadecimal, and octal numbers given by the following grammar:

    > DecodableString:
    >   Signopt DecimalNumeral
    >   Signopt `0x` HexDigits
    >   Signopt `0X` HexDigits
    >   Signopt `#` HexDigits
    >   Signopt `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 `Long.parseLong` 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:
      a `Long` object holding the `long` value represented by `nm`
    Throws:
      `NumberFormatException` - if the `String` does not contain a parsable `long`.
    Since:
      1.2
    See Also:
      - `parseLong(String, int)`

  - ### byteValue

    public byte byteValue()
    Returns the value of this `Long` as a `byte` after a narrowing primitive conversion.
    Overrides:
      `byteValue` in class `Number`
    Returns:
      the numeric value represented by this object after conversion to type `byte`.
    See Java Language Specification:
      5.1.3 Narrowing Primitive Conversion

  - ### shortValue

    public short shortValue()
    Returns the value of this `Long` as a `short` after a narrowing primitive conversion.
    Overrides:
      `shortValue` in class `Number`
    Returns:
      the numeric value represented by this object after conversion to type `short`.
    See Java Language Specification:
      5.1.3 Narrowing Primitive Conversion

  - ### intValue

    public int intValue()
    Returns the value of this `Long` as an `int` after a narrowing primitive conversion.
    Specified by:
      `intValue` in class `Number`
    Returns:
      the numeric value represented by this object after conversion to type `int`.
    See Java Language Specification:
      5.1.3 Narrowing Primitive Conversion

  - ### longValue

    public long longValue()
    Returns the value of this `Long` as a `long` value.
    Specified by:
      `longValue` in class `Number`
    Returns:
      the numeric value represented by this object after conversion to type `long`.

  - ### floatValue

    public float floatValue()
    Returns the value of this `Long` as a `float` after a widening primitive conversion.
    Specified by:
      `floatValue` in class `Number`
    Returns:
      the numeric value represented by this object after conversion to type `float`.
    See Java Language Specification:
      5.1.2 Widening Primitive Conversion

  - ### doubleValue

    public double doubleValue()
    Returns the value of this `Long` as a `double` after a widening primitive conversion.
    Specified by:
      `doubleValue` in class `Number`
    Returns:
      the numeric value represented by this object after conversion to type `double`.
    See Java Language Specification:
      5.1.2 Widening Primitive Conversion

  - ### toString

    public String toString()
    Returns a `String` object representing this `Long`'s value. The value is converted to signed decimal representation and returned as a string, exactly as if the `long` value were given as an argument to the `toString(long)` method.
    Overrides:
      `toString` in class `Object`
    Returns:
      a string representation of the value of this object in base 10.

  - ### hashCode

    public int hashCode()
    Returns a hash code for this `Long`. The result is the exclusive OR of the two halves of the primitive `long` value held by this `Long` object. That is, the hashcode is the value of the expression:

    > `(int)(this.longValue()^(this.longValue()>>>32))`

    Overrides:
      `hashCode` in class `Object`
    Returns:
      a hash code value for this object.
    See Also:
      - `Object.equals(java.lang.Object)`
      - `System.identityHashCode(Object)`

  - ### hashCode

    public static int hashCode(long value)
    Returns a hash code for a `long` value; compatible with `Long.hashCode()`.
    Parameters:
      `value` - the value to hash
    Returns:
      a hash code value for a `long` value.
    Since:
      1.8

  - ### 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 a `Long` object that contains the same `long` value as this object.
    Overrides:
      `equals` in class `Object`
    Parameters:
      `obj` - the object to compare with.
    Returns:
      `true` if the objects are the same; `false` otherwise.
    See Also:
      - `Object.hashCode()`
      - `HashMap`

  - ### getLong

    public static Long getLong(String nm)
    Determines the `long` 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 a `long` value using the grammar supported by `decode` and a `Long` 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 a `Long` object equal to the value of:

    > `getLong(nm, null)`

    Parameters:
      `nm` - property name.
    Returns:
      the `Long` value of the property.
    See Also:
      - `System.getProperty(java.lang.String)`
      - `System.getProperty(java.lang.String, java.lang.String)`

  - ### getLong

    public static Long getLong(String nm, long val)
    Determines the `long` 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 a `long` value using the grammar supported by `decode` and a `Long` object representing this value is returned.

    The second argument is the default value. A `Long` 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 a `Long` object equal to the value of:

    > `getLong(nm, Long.valueOf(val))`

    but in practice it may be implemented in a manner such as:

    >     Long result = getLong(nm, null);
    >     return (result == null) ? Long.valueOf(val) : result;

    to avoid the unnecessary allocation of a `Long` object when the default value is not needed.
    Parameters:
      `nm` - property name.
      `val` - default value.
    Returns:
      the `Long` value of the property.
    See Also:
      - `System.getProperty(java.lang.String)`
      - `System.getProperty(java.lang.String, java.lang.String)`

  - ### getLong

    public static Long getLong(String nm, Long val)
    Returns the `long` 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 a `long` value, as per the `decode` method, and a `Long` 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 for 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.

    Note that, in every case, neither `L` (`'\u004C'`) nor `l` (`'\u006C'`) is permitted to appear at the end of the property value as a type indicator, as would be permitted in Java programming language source code.

    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 `Long` value of the property.
    See Also:
      - `System.getProperty(java.lang.String)`
      - `System.getProperty(java.lang.String, java.lang.String)`

  - ### compareTo

    public int compareTo(Long anotherLong)
    Compares two `Long` objects numerically.
    Specified by:
      `compareTo` in interface `Comparable<Long>`
    Parameters:
      `anotherLong` - the `Long` to be compared.
    Returns:
      the value `0` if this `Long` is equal to the argument `Long`; a value less than `0` if this `Long` is numerically less than the argument `Long`; and a value greater than `0` if this `Long` is numerically greater than the argument `Long` (signed comparison).
    Since:
      1.2

  - ### compare

    public static int compare(long x, long y)
    Compares two `long` values numerically. The value returned is identical to what would be returned by:

           Long.valueOf(x).compareTo(Long.valueOf(y))

    Parameters:
      `x` - the first `long` to compare
      `y` - the second `long` 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`
    Since:
      1.7

  - ### compareUnsigned

    public static int compareUnsigned(long x, long y)
    Compares two `long` values numerically treating the values as unsigned.
    Parameters:
      `x` - the first `long` to compare
      `y` - the second `long` 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
    Since:
      1.8

  - ### divideUnsigned

    public static long divideUnsigned(long dividend, long 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
    Since:
      1.8
    See Also:
      - `remainderUnsigned(long, long)`

  - ### remainderUnsigned

    public static long remainderUnsigned(long dividend, long 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
    Since:
      1.8
    See Also:
      - `divideUnsigned(long, long)`

  - ### highestOneBit

    public static long highestOneBit(long i)
    Returns a `long` value with at most a single one-bit, in the position of the highest-order ("leftmost") one-bit in the specified `long` 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:
      a `long` 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.
    Since:
      1.5

  - ### lowestOneBit

    public static long lowestOneBit(long i)
    Returns a `long` value with at most a single one-bit, in the position of the lowest-order ("rightmost") one-bit in the specified `long` 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:
      a `long` 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.
    Since:
      1.5

  - ### numberOfLeadingZeros

    public static int numberOfLeadingZeros(long i)
    Returns the number of zero bits preceding the highest-order ("leftmost") one-bit in the two's complement binary representation of the specified `long` value. Returns 64 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 `long` values x:

    - floor(log2(x)) = `63 - numberOfLeadingZeros(x)`
    - ceil(log2(x)) = `64 - 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 `long` value, or 64 if the value is equal to zero.
    Since:
      1.5

  - ### numberOfTrailingZeros

    public static int numberOfTrailingZeros(long i)
    Returns the number of zero bits following the lowest-order ("rightmost") one-bit in the two's complement binary representation of the specified `long` value. Returns 64 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 `long` value, or 64 if the value is equal to zero.
    Since:
      1.5

  - ### bitCount

    public static int bitCount(long i)
    Returns the number of one-bits in the two's complement binary representation of the specified `long` 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 `long` value.
    Since:
      1.5

  - ### rotateLeft

    public static long rotateLeft(long i, int distance)
    Returns the value obtained by rotating the two's complement binary representation of the specified `long` 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 64 is a no-op, so all but the last six bits of the rotation distance can be ignored, even if the distance is negative: `rotateLeft(val, distance) == rotateLeft(val, distance & 0x3F)`.

    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 `long` value left by the specified number of bits.
    Since:
      1.5

  - ### rotateRight

    public static long rotateRight(long i, int distance)
    Returns the value obtained by rotating the two's complement binary representation of the specified `long` 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 64 is a no-op, so all but the last six bits of the rotation distance can be ignored, even if the distance is negative: `rotateRight(val, distance) == rotateRight(val, distance & 0x3F)`.

    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 `long` value right by the specified number of bits.
    Since:
      1.5

  - ### reverse

    public static long reverse(long i)
    Returns the value obtained by reversing the order of the bits in the two's complement binary representation of the specified `long` value.
    Parameters:
      `i` - the value to be reversed
    Returns:
      the value obtained by reversing order of the bits in the specified `long` value.
    Since:
      1.5

  - ### compress

    public static long compress(long i, long mask)
    Returns the value obtained by compressing the bits of the specified `long` value, `i`, in accordance with the specified bit mask.

    For each one-bit value `mb` of the mask, from least significant to most significant, the bit value of `i` at the same bit location as `mb` is assigned to the compressed value contiguously starting from the least significant bit location. All the upper remaining bits of the compressed value are set to zero.

    API Note:
      Consider the simple case of compressing the digits of a hexadecimal value:

          // Compressing drink to food
          compress(0xCAFEBABEL, 0xFF00FFF0L) == 0xCABABL

      Starting from the least significant hexadecimal digit at position 0 from the right, the mask `0xFF00FFF0` selects hexadecimal digits at positions 1, 2, 3, 6 and 7 of `0xCAFEBABE`. The selected digits occur in the resulting compressed value contiguously from digit position 0 in the same order.

      The following identities all return `true` and are helpful to understand the behaviour of `compress`:

          // Returns 1 if the bit at position n is one
          compress(x, 1L << n) == (x >> n & 1)

          // Logical shift right
          compress(x, -1L << n) == x >>> n

          // Any bits not covered by the mask are ignored
          compress(x, m) == compress(x & m, m)

          // Compressing a value by itself
          compress(m, m) == (m == -1 || m == 0) ? m : (1L << bitCount(m)) - 1

          // Expanding then compressing with the same mask
          compress(expand(x, m), m) == x & compress(m, m)

      The Sheep And Goats (SAG) operation (see Hacker's Delight, Second Edition, section 7.7) can be implemented as follows:

          long compressLeft(long i, long mask) {
              // This implementation follows the description in Hacker's Delight which
              // is informative. A more optimal implementation is:
              //   Long.compress(i, mask) << -Long.bitCount(mask)
              return Long.reverse(
                  Long.compress(Long.reverse(i), Long.reverse(mask)));
          }

          long sag(long i, long mask) {
              return compressLeft(i, mask) | Long.compress(i, ~mask);
          }

          // Separate the sheep from the goats
          sag(0x00000000_CAFEBABEL, 0xFFFFFFFF_FF00FFF0L) == 0x00000000_CABABFEEL

    Parameters:
      `i` - the value whose bits are to be compressed
      `mask` - the bit mask
    Returns:
      the compressed value
    Since:
      19
    See Also:
      - `expand(long, long)`

  - ### expand

    public static long expand(long i, long mask)
    Returns the value obtained by expanding the bits of the specified `long` value, `i`, in accordance with the specified bit mask.

    For each one-bit value `mb` of the mask, from least significant to most significant, the next contiguous bit value of `i` starting at the least significant bit is assigned to the expanded value at the same bit location as `mb`. All other remaining bits of the expanded value are set to zero.

    API Note:
      Consider the simple case of expanding the digits of a hexadecimal value:

          expand(0x0000CABABL, 0xFF00FFF0L) == 0xCA00BAB0L

      Starting from the least significant hexadecimal digit at position 0 from the right, the mask `0xFF00FFF0` selects the first five hexadecimal digits of `0x0000CABAB`. The selected digits occur in the resulting expanded value in order at positions 1, 2, 3, 6, and 7.

      The following identities all return `true` and are helpful to understand the behaviour of `expand`:

          // Logically shift right the bit at position 0
          expand(x, 1L << n) == (x & 1) << n

          // Logically shift right
          expand(x, -1L << n) == x << n

          // Expanding all bits returns the mask
          expand(-1L, m) == m

          // Any bits not covered by the mask are ignored
          expand(x, m) == expand(x, m) & m

          // Compressing then expanding with the same mask
          expand(compress(x, m), m) == x & m

      The select operation for determining the position of the one-bit with index `n` in a `long` value can be implemented as follows:

          long select(long i, long n) {
              // the one-bit in i (the mask) with index n
              long nthBit = Long.expand(1L << n, i);
              // the bit position of the one-bit with index n
              return Long.numberOfTrailingZeros(nthBit);
          }

          // The one-bit with index 0 is at bit position 1
          select(0b10101010_10101010, 0) == 1
          // The one-bit with index 3 is at bit position 7
          select(0b10101010_10101010, 3) == 7

    Parameters:
      `i` - the value whose bits are to be expanded
      `mask` - the bit mask
    Returns:
      the expanded value
    Since:
      19
    See Also:
      - `compress(long, long)`

  - ### signum

    public static int signum(long i)
    Returns the signum function of the specified `long` 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 `long` value.
    Since:
      1.5

  - ### reverseBytes

    public static long reverseBytes(long i)
    Returns the value obtained by reversing the order of the bytes in the two's complement representation of the specified `long` value.
    Parameters:
      `i` - the value whose bytes are to be reversed
    Returns:
      the value obtained by reversing the bytes in the specified `long` value.
    Since:
      1.5

  - ### sum

    public static long sum(long a, long b)
    Adds two `long` values together as per the + operator.
    Parameters:
      `a` - the first operand
      `b` - the second operand
    Returns:
      the sum of `a` and `b`
    Since:
      1.8
    See Also:
      - `BinaryOperator`

  - ### max

    public static long max(long a, long b)
    Returns the greater of two `long` values as if by calling `Math.max`.
    Parameters:
      `a` - the first operand
      `b` - the second operand
    Returns:
      the greater of `a` and `b`
    Since:
      1.8
    See Also:
      - `BinaryOperator`

  - ### min

    public static long min(long a, long b)
    Returns the smaller of two `long` values as if by calling `Math.min`.
    Parameters:
      `a` - the first operand
      `b` - the second operand
    Returns:
      the smaller of `a` and `b`
    Since:
      1.8
    See Also:
      - `BinaryOperator`

  - ### describeConstable

    public Optional<Long> describeConstable()
    Returns an `Optional` containing the nominal descriptor for this instance, which is the instance itself.
    Specified by:
      `describeConstable` in interface `Constable`
    Returns:
      an `Optional` describing the Long instance
    Since:
      12

  - ### resolveConstantDesc

    public Long resolveConstantDesc(MethodHandles.Lookup lookup)
    Resolves this instance as a `ConstantDesc`, the result of which is the instance itself.
    Specified by:
      `resolveConstantDesc` in interface `ConstantDesc`
    Parameters:
      `lookup` - ignored
    Returns:
      the Long instance
    Since:
      12