Class Long

java.lang.Object
java.lang.Number
java.lang.Long
All Implemented Interfaces:
Serializable,Comparable<Long>,Constable,ConstantDesc

public final classLongextendsNumberimplementsComparable<Long>,Constable,ConstantDesc
TheLong class is thewrapper class for values of the primitivetypelong. An object of typeLong contains asingle field whose type islong.

In addition, this class provides several methods for convertingalong to aString and aString to along, as well as other constants and methods useful when dealingwith along.

This is avalue-basedclass; programmers should treat instances that areequal as interchangeable and should notuse instances for synchronization, or unpredictable behavior mayoccur. For example, in a future release, synchronization may fail.

Implementation note: The implementations of the "bit twiddling"methods (such ashighestOneBit andnumberOfTrailingZeros) arebased on material from Henry S. Warren, Jr.'sHacker'sDelight, (Addison Wesley, 2002) andHacker'sDelight, Second Edition, (Pearson Education, 2013).

Since:
1.0
See Also:
  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    static final int
    The number of bytes used to represent along value in two'scomplement binary form.
    static final long
    A constant holding the maximum value along canhave, 263-1.
    static final long
    A constant holding the minimum value along canhave, -263.
    static final int
    The number of bits used to represent along value in two'scomplement binary form.
    static finalClass<Long>
    TheClass instance representing the primitive typelong.
  • Constructor Summary

    Constructors
    Constructor
    Description
    Long(long value)
    Deprecated.
    It is rarely appropriate to use this constructor.
    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 binaryrepresentation of the specifiedlong value.
    byte
    Returns the value of thisLong as abyte aftera narrowing primitive conversion.
    static int
    compare(long x, long y)
    Compares twolong values numerically.
    int
    compareTo(Long anotherLong)
    Compares twoLong objects numerically.
    static int
    compareUnsigned(long x, long y)
    Compares twolong values numerically treating the valuesas unsigned.
    static long
    compress(long i, long mask)
    Returns the value obtained by compressing the bits of thespecifiedlong value,i, in accordance withthe specified bit mask.
    staticLong
    Decodes aString into aLong.
    Returns anOptional containing the nominal descriptor for thisinstance, which is the instance itself.
    static long
    divideUnsigned(long dividend, long divisor)
    Returns the unsigned quotient of dividing the first argument bythe second where each argument and the result is interpreted asan unsigned value.
    double
    Returns the value of thisLong as adoubleafter a widening primitive conversion.
    boolean
    Compares this object to the specified object.
    static long
    expand(long i, long mask)
    Returns the value obtained by expanding the bits of thespecifiedlong value,i, in accordance withthe specified bit mask.
    float
    Returns the value of thisLong as afloat aftera widening primitive conversion.
    staticLong
    Determines thelong value of the system propertywith the specified name.
    staticLong
    getLong(String nm, long val)
    Determines thelong value of the system propertywith the specified name.
    staticLong
    getLong(String nm,Long val)
    Returns thelong value of the system property withthe specified name.
    int
    Returns a hash code for thisLong.
    static int
    hashCode(long value)
    Returns a hash code for along value; compatible withLong.hashCode().
    static long
    highestOneBit(long i)
    Returns along value with at most a single one-bit, in theposition of the highest-order ("leftmost") one-bit in the specifiedlong value.
    int
    Returns the value of thisLong as anint aftera narrowing primitive conversion.
    long
    Returns the value of thisLong as along value.
    static long
    lowestOneBit(long i)
    Returns along value with at most a single one-bit, in theposition of the lowest-order ("rightmost") one-bit in the specifiedlong value.
    static long
    max(long a, long b)
    Returns the greater of twolong valuesas if by callingMath.max.
    static long
    min(long a, long b)
    Returns the smaller of twolong valuesas if by callingMath.min.
    static int
    Returns the number of zero bits preceding the highest-order("leftmost") one-bit in the two's complement binary representationof the specifiedlong value.
    static int
    Returns the number of zero bits following the lowest-order ("rightmost")one-bit in the two's complement binary representation of the specifiedlong value.
    static long
    parseLong(CharSequence s, int beginIndex, int endIndex, int radix)
    Parses theCharSequence argument as a signedlong inthe specifiedradix, beginning at the specifiedbeginIndex and extending toendIndex - 1.
    static long
    Parses the string argument as a signed decimallong.
    static long
    parseLong(String s, int radix)
    Parses the string argument as a signedlong in theradix specified by the second argument.
    static long
    parseUnsignedLong(CharSequence s, int beginIndex, int endIndex, int radix)
    Parses theCharSequence argument as an unsignedlong inthe specifiedradix, beginning at the specifiedbeginIndex and extending toendIndex - 1.
    static long
    Parses the string argument as an unsigned decimallong.
    static long
    parseUnsignedLong(String s, int radix)
    Parses the string argument as an unsignedlong in theradix specified by the second argument.
    static long
    remainderUnsigned(long dividend, long divisor)
    Returns the unsigned remainder from dividing the first argumentby the second where each argument and the result is interpretedas an unsigned value.
    Resolves this instance as aConstantDesc, the result of which isthe instance itself.
    static long
    reverse(long i)
    Returns the value obtained by reversing the order of the bits in thetwo's complement binary representation of the specifiedlongvalue.
    static long
    reverseBytes(long i)
    Returns the value obtained by reversing the order of the bytes in thetwo's complement representation of the specifiedlong value.
    static long
    rotateLeft(long i, int distance)
    Returns the value obtained by rotating the two's complement binaryrepresentation of the specifiedlong value left by thespecified number of bits.
    static long
    rotateRight(long i, int distance)
    Returns the value obtained by rotating the two's complement binaryrepresentation of the specifiedlong value right by thespecified number of bits.
    short
    Returns the value of thisLong as ashort aftera narrowing primitive conversion.
    static int
    signum(long i)
    Returns the signum function of the specifiedlong value.
    static long
    sum(long a, long b)
    Adds twolong values together as per the + operator.
    staticString
    Returns a string representation of thelongargument as an unsigned integer in base 2.
    staticString
    toHexString(long i)
    Returns a string representation of thelongargument as an unsigned integer in base 16.
    staticString
    toOctalString(long i)
    Returns a string representation of thelongargument as an unsigned integer in base 8.
    Returns aString object representing thisLong's value.
    staticString
    toString(long i)
    Returns aString object representing the specifiedlong.
    staticString
    toString(long i, int radix)
    Returns a string representation of the first argument in theradix specified by the second argument.
    staticString
    Returns a string representation of the argument as an unsigneddecimal value.
    staticString
    toUnsignedString(long i, int radix)
    Returns a string representation of the first argument as anunsigned integer value in the radix specified by the secondargument.
    staticLong
    valueOf(long l)
    Returns aLong instance representing the specifiedlong value.
    staticLong
    Returns aLong object holding the valueof the specifiedString.
    staticLong
    valueOf(String s, int radix)
    Returns aLong object holding the valueextracted from the specifiedString when parsedwith the radix given by the second argument.
  • Field Details

    • MIN_VALUE

      @Nativepublic static final long MIN_VALUE
      A constant holding the minimum value along canhave, -263.
      See Also:
    • MAX_VALUE

      @Nativepublic static final long MAX_VALUE
      A constant holding the maximum value along canhave, 263-1.
      See Also:
    • TYPE

      public static final Class<Long> TYPE
      TheClass instance representing the primitive typelong.
      Since:
      1.1
    • SIZE

      @Nativepublic static final int SIZE
      The number of bits used to represent along value in two'scomplement binary form.
      Since:
      1.5
      See Also:
    • BYTES

      public static final int BYTES
      The number of bytes used to represent along value in two'scomplement binary form.
      Since:
      1.8
      See Also:
  • Constructor Details

    • Long

      @Deprecated(since="9")public Long(long value)
      Deprecated.
      It is rarely appropriate to use this constructor. The static factoryvalueOf(long) is generally a better choice, as it islikely to yield significantly better space and time performance.
      Constructs a newly allocatedLong object thatrepresents the specifiedlong argument.
      Parameters:
      value - the value to be represented by theLong object.
    • Long

      @Deprecated(since="9")public Long(String s) throwsNumberFormatException
      Deprecated.
      It is rarely appropriate to use this constructor.UseparseLong(String) to convert a string to along primitive, or usevalueOf(String)to convert a string to aLong object.
      Constructs a newly allocatedLong object thatrepresents thelong value indicated by theString parameter. The string is converted to along value in exactly the manner used by theparseLong method for radix 10.
      Parameters:
      s - theString to be converted to aLong.
      Throws:
      NumberFormatException - if theString does not contain a parsablelong.
  • Method Details

    • toString

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

      If the radix is smaller thanCharacter.MIN_RADIXor larger thanCharacter.MAX_RADIX, then the radix10 is used instead.

      If the first argument is negative, the first element of theresult is the ASCII minus sign'-'('\u002d'). If the first argument is notnegative, no sign character appears in the result.

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

      0123456789abcdefghijklmnopqrstuvwxyz
      These are'\u0030' through'\u0039' and'\u0061' through'\u007a'. Ifradix isN, then the firstN of these charactersare used as radix-N digits in the order shown. Thus,the digits for hexadecimal (radix 16) are0123456789abcdef. If uppercase letters aredesired, theString.toUpperCase() method maybe called on the result:
      Long.toString(n, 16).toUpperCase()

      Parameters:
      i - along 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:
    • toUnsignedString

      public static String toUnsignedString(long i, int radix)
      Returns a string representation of the first argument as anunsigned integer value in the radix specified by the secondargument.

      If the radix is smaller thanCharacter.MIN_RADIXor larger thanCharacter.MAX_RADIX, then the radix10 is used instead.

      Note that since the first argument is treated as an unsignedvalue, no leading sign character is printed.

      If the magnitude is zero, it is represented by a single zerocharacter'0' ('\u0030'); otherwise,the first character of the representation of the magnitude willnot be the zero character.

      The behavior of radixes and the characters used as digitsare the same astoString.

      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:
    • toHexString

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

      The unsignedlong value is the argument plus264 if the argument is negative; otherwise, it isequal to the argument. This value is converted to a string ofASCII digits in hexadecimal (base 16) with no extraleading0s.

      The value of the argument can be recovered from the returnedstrings by callingLong.parseUnsignedLong(s,16).

      If the unsigned magnitude is zero, it is represented by asingle zero character'0' ('\u0030');otherwise, the first character of the representation of theunsigned magnitude will not be the zero character. Thefollowing characters are used as hexadecimal digits:

      0123456789abcdef
      These are the characters'\u0030' through'\u0039' and'\u0061' through'\u0066'. If uppercase letters are desired,theString.toUpperCase() method may be calledon the result:
      Long.toHexString(n).toUpperCase()

      API Note:
      TheHexFormat class provides formatting and parsingof byte arrays and primitives to return a string or adding to anAppendable.HexFormat formats and parses uppercase or lowercase hexadecimal characters,with leading zeros and for byte arrays includes for each bytea delimiter, prefix, and suffix.
      Parameters:
      i - along to be converted to a string.
      Returns:
      the string representation of the unsignedlong value represented by the argument in hexadecimal (base 16).
      Since:
      1.0.2
      See Also:
    • toOctalString

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

      The unsignedlong value is the argument plus264 if the argument is negative; otherwise, it isequal to the argument. This value is converted to a string ofASCII digits in octal (base 8) with no extra leading0s.

      The value of the argument can be recovered from the returnedstrings by callingLong.parseUnsignedLong(s,8).

      If the unsigned magnitude is zero, it is represented by asingle zero character'0' ('\u0030');otherwise, the first character of the representation of theunsigned magnitude will not be the zero character. Thefollowing characters are used as octal digits:

      01234567
      These are the characters'\u0030' through'\u0037'.

      Parameters:
      i - along to be converted to a string.
      Returns:
      the string representation of the unsignedlong value represented by the argument in octal (base 8).
      Since:
      1.0.2
      See Also:
    • toBinaryString

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

      The unsignedlong value is the argument plus264 if the argument is negative; otherwise, it isequal to the argument. This value is converted to a string ofASCII digits in binary (base 2) with no extra leading0s.

      The value of the argument can be recovered from the returnedstrings by callingLong.parseUnsignedLong(s,2).

      If the unsigned magnitude is zero, it is represented by asingle zero character'0' ('\u0030');otherwise, the first character of the representation of theunsigned magnitude will not be the zero character. Thecharacters'0' ('\u0030') and'1' ('\u0031') are used as binary digits.

      Parameters:
      i - along to be converted to a string.
      Returns:
      the string representation of the unsignedlong value represented by the argument in binary (base 2).
      Since:
      1.0.2
      See Also:
    • toString

      public static String toString(long i)
      Returns aString object representing the specifiedlong. The argument is converted to signed decimalrepresentation and returned as a string, exactly as if theargument and the radix 10 were given as arguments to thetoString(long, int) method.
      Parameters:
      i - along 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 unsigneddecimal value.The argument is converted to unsigned decimal representationand returned as a string exactly as if the argument and radix10 were given as arguments to thetoUnsignedString(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:
    • parseLong

      public static long parseLong(String s, int radix) throwsNumberFormatException
      Parses the string argument as a signedlong in theradix specified by the second argument. The characters in thestring must all be digits of the specified radix (as determinedby whetherCharacter.digit(char, int) returnsa nonnegative value), except that the first character may be anASCII minus sign'-' ('\u002D') toindicate a negative value or an ASCII plus sign'+'('\u002B') to indicate a positive value. Theresultinglong value is returned.

      Note that neither the characterL('\u004C') norl('\u006C') is permitted to appear at the endof the string as a type indicator, as would be permitted inJava programming language source code - except that eitherL orl may appear as a digit for aradix greater than or equal to 22.

      An exception of typeNumberFormatException isthrown if any of the following situations occurs:

      • The first argument isnull or is a string oflength zero.
      • Theradix is either smaller thanCharacter.MIN_RADIX or larger thanCharacter.MAX_RADIX.
      • Any character of the string is not a digit of the specifiedradix, except that the first character may be a minus sign'-' ('\u002d') or plus sign'+' ('\u002B') provided that the string islonger than length 1.
      • The value represented by the string is not a value of typelong.

      Examples:

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

      Parameters:
      s - theString containing thelong representation to be parsed.
      radix - the radix to be used while parsings.
      Returns:
      thelong represented by the string argument in the specified radix.
      Throws:
      NumberFormatException - if the string does not contain a parsablelong.
    • parseLong

      public static long parseLong(CharSequence s, int beginIndex, int endIndex, int radix) throwsNumberFormatException
      Parses theCharSequence argument as a signedlong inthe specifiedradix, beginning at the specifiedbeginIndex and extending toendIndex - 1.

      The method does not take steps to guard against theCharSequence being mutated while parsing.

      Parameters:
      s - theCharSequence containing thelong representation to be parsed
      beginIndex - the beginning index, inclusive.
      endIndex - the ending index, exclusive.
      radix - the radix to be used while parsings.
      Returns:
      the signedlong represented by the subsequence in the specified radix.
      Throws:
      NullPointerException - ifs is null.
      IndexOutOfBoundsException - ifbeginIndex is negative, or ifbeginIndex is greater thanendIndex or ifendIndex is greater thans.length().
      NumberFormatException - if theCharSequence does not contain a parsablelong in the specifiedradix, or ifradix is either smaller thanCharacter.MIN_RADIX or larger thanCharacter.MAX_RADIX.
      Since:
      9
    • parseLong

      public static long parseLong(String s) throwsNumberFormatException
      Parses the string argument as a signed decimallong.The characters in the string must all be decimal digits, exceptthat the first character may be an ASCII minus sign'-'(\u002D') to indicate a negative value or anASCII plus sign'+' ('\u002B') toindicate a positive value. The resultinglong value isreturned, exactly as if the argument and the radix10were given as arguments to theparseLong(java.lang.String, int) method.

      Note that neither the characterL('\u004C') norl('\u006C') is permitted to appear at the endof the string as a type indicator, as would be permitted inJava programming language source code.

      Parameters:
      s - aString containing thelong representation to be parsed
      Returns:
      thelong represented by the argument in decimal.
      Throws:
      NumberFormatException - if the string does not contain a parsablelong.
    • parseUnsignedLong

      public static long parseUnsignedLong(String s, int radix) throwsNumberFormatException
      Parses the string argument as an unsignedlong in theradix specified by the second argument. An unsigned integermaps the values usually associated with negative numbers topositive numbers larger thanMAX_VALUE.The characters in the string must all be digits of thespecified radix (as determined by whetherCharacter.digit(char, int) returns a nonnegativevalue), except that the first character may be an ASCII plussign'+' ('\u002B'). The resultinginteger value is returned.

      An exception of typeNumberFormatException isthrown if any of the following situations occurs:

      • The first argument isnull or is a string oflength zero.
      • The radix is either smaller thanCharacter.MIN_RADIX orlarger thanCharacter.MAX_RADIX.
      • Any character of the string is not a digit of the specifiedradix, except that the first character may be a plus sign'+' ('\u002B') provided that thestring is longer than length 1.
      • The value represented by the string is larger than thelargest unsignedlong, 264-1.

      Parameters:
      s - theString containing the unsigned integer representation to be parsed
      radix - the radix to be used while parsings.
      Returns:
      the unsignedlong represented by the string argument in the specified radix.
      Throws:
      NumberFormatException - if theString does not contain a parsablelong.
      Since:
      1.8
    • parseUnsignedLong

      public static long parseUnsignedLong(CharSequence s, int beginIndex, int endIndex, int radix) throwsNumberFormatException
      Parses theCharSequence argument as an unsignedlong inthe specifiedradix, beginning at the specifiedbeginIndex and extending toendIndex - 1.

      The method does not take steps to guard against theCharSequence being mutated while parsing.

      Parameters:
      s - theCharSequence containing the unsignedlong representation to be parsed
      beginIndex - the beginning index, inclusive.
      endIndex - the ending index, exclusive.
      radix - the radix to be used while parsings.
      Returns:
      the unsignedlong represented by the subsequence in the specified radix.
      Throws:
      NullPointerException - ifs is null.
      IndexOutOfBoundsException - ifbeginIndex is negative, or ifbeginIndex is greater thanendIndex or ifendIndex is greater thans.length().
      NumberFormatException - if theCharSequence does not contain a parsable unsignedlong in the specifiedradix, or ifradix is either smaller thanCharacter.MIN_RADIX or larger thanCharacter.MAX_RADIX.
      Since:
      9
    • parseUnsignedLong

      public static long parseUnsignedLong(String s) throwsNumberFormatException
      Parses the string argument as an unsigned decimallong. Thecharacters in the string must all be decimal digits, exceptthat the first character may be an ASCII plus sign'+' ('\u002B'). The resulting integer valueis returned, exactly as if the argument and the radix 10 weregiven as arguments to theparseUnsignedLong(java.lang.String, int) method.
      Parameters:
      s - aString containing the unsignedlong representation to be parsed
      Returns:
      the unsignedlong 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) throwsNumberFormatException
      Returns aLong object holding the valueextracted from the specifiedString when parsedwith the radix given by the second argument. The firstargument is interpreted as representing a signedlong in the radix specified by the secondargument, exactly as if the arguments were given to theparseLong(java.lang.String, int) method. The result is aLong object that represents thelongvalue specified by the string.

      In other words, this method returns aLong object equalto the value of:

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

      Parameters:
      s - the string to be parsed
      radix - the radix to be used in interpretings
      Returns:
      aLong object holding the value represented by the string argument in the specified radix.
      Throws:
      NumberFormatException - If theString does not contain a parsablelong.
    • valueOf

      public static Long valueOf(String s) throwsNumberFormatException
      Returns aLong object holding the valueof the specifiedString. The argument isinterpreted as representing a signed decimallong,exactly as if the argument were given to theparseLong(java.lang.String) method. The result is aLong object that represents the integer valuespecified by the string.

      In other words, this method returns aLong objectequal to the value of:

      Long.valueOf(Long.parseLong(s))

      Parameters:
      s - the string to be parsed.
      Returns:
      aLong object holding the value represented by the string argument.
      Throws:
      NumberFormatException - If the string cannot be parsed as along.
    • valueOf

      public static Long valueOf(long l)
      Returns aLong instance representing the specifiedlong value.If a newLong instance is not required, this methodshould generally be used in preference to the constructorLong(long), as this method is likely to yieldsignificantly better space and time performance by cachingfrequently 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:
      aLong instance representingl.
      Since:
      1.5
    • decode

      public static Long decode(String nm) throwsNumberFormatException
      Decodes aString into aLong.Accepts decimal, hexadecimal, and octal numbers given by thefollowing grammar:
      DecodableString:
      Signopt DecimalNumeral
      Signopt0xHexDigits
      Signopt0XHexDigits
      Signopt#HexDigits
      Signopt0OctalDigits
      Sign:
      -
      +
      DecimalNumeral,HexDigits, andOctalDigitsare as defined in section3.10.1 ofThe Java Language Specification,except that underscores are not accepted between digits.

      The sequence of characters following an optionalsign and/or radix specifier ("0x", "0X","#", or leading zero) is parsed as by theLong.parseLong method with the indicated radix (10, 16, or 8).This sequence of characters must represent a positive value oraNumberFormatException will be thrown. The result isnegated if first character of the specifiedString isthe minus sign. No whitespace characters are permitted in theString.

      Parameters:
      nm - theString to decode.
      Returns:
      aLong object holding thelong value represented bynm
      Throws:
      NumberFormatException - if theString does not contain a parsablelong.
      Since:
      1.2
      See Also:
    • byteValue

      public byte byteValue()
      Returns the value of thisLong as abyte aftera narrowing primitive conversion.
      Overrides:
      byteValue in class Number
      Returns:
      the numeric value represented by this object after conversion to typebyte.
      SeeJava Language Specification:
      5.1.3 Narrowing Primitive Conversion
    • shortValue

      public short shortValue()
      Returns the value of thisLong as ashort aftera narrowing primitive conversion.
      Overrides:
      shortValue in class Number
      Returns:
      the numeric value represented by this object after conversion to typeshort.
      SeeJava Language Specification:
      5.1.3 Narrowing Primitive Conversion
    • intValue

      public int intValue()
      Returns the value of thisLong as anint aftera narrowing primitive conversion.
      Specified by:
      intValue in class Number
      Returns:
      the numeric value represented by this object after conversion to typeint.
      SeeJava Language Specification:
      5.1.3 Narrowing Primitive Conversion
    • longValue

      public long longValue()
      Returns the value of thisLong as along value.
      Specified by:
      longValue in class Number
      Returns:
      the numeric value represented by this object after conversion to typelong.
    • floatValue

      public float floatValue()
      Returns the value of thisLong as afloat aftera widening primitive conversion.
      Specified by:
      floatValue in class Number
      Returns:
      the numeric value represented by this object after conversion to typefloat.
      SeeJava Language Specification:
      5.1.2 Widening Primitive Conversion
    • doubleValue

      public double doubleValue()
      Returns the value of thisLong as adoubleafter a widening primitive conversion.
      Specified by:
      doubleValue in class Number
      Returns:
      the numeric value represented by this object after conversion to typedouble.
      SeeJava Language Specification:
      5.1.2 Widening Primitive Conversion
    • toString

      public String toString()
      Returns aString object representing thisLong's value. The value is converted to signeddecimal representation and returned as a string, exactly as ifthelong value were given as an argument to thetoString(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 thisLong. The result isthe exclusive OR of the two halves of the primitivelong value held by thisLongobject. 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:
    • hashCode

      public static int hashCode(long value)
      Returns a hash code for along value; compatible withLong.hashCode().
      Parameters:
      value - the value to hash
      Returns:
      a hash code value for along value.
      Since:
      1.8
    • equals

      public boolean equals(Object obj)
      Compares this object to the specified object. The result istrue if and only if the argument is notnull and is aLong object thatcontains the samelong 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:
    • getLong

      public static Long getLong(String nm)
      Determines thelong value of the system propertywith the specified name.

      The first argument is treated as the name of a systemproperty. System properties are accessible through theSystem.getProperty(java.lang.String) method. Thestring value of this property is then interpreted as along value using the grammar supported bydecodeand aLong object representing this value is returned.

      If there is no property with the specified name, if thespecified name is empty ornull, or if the propertydoes not have the correct numeric format, thennull isreturned.

      In other words, this method returns aLong objectequal to the value of:

      getLong(nm, null)

      Parameters:
      nm - property name.
      Returns:
      theLong value of the property.
      See Also:
    • getLong

      public static Long getLong(String nm, long val)
      Determines thelong value of the system propertywith the specified name.

      The first argument is treated as the name of a systemproperty. System properties are accessible through theSystem.getProperty(java.lang.String) method. Thestring value of this property is then interpreted as along value using the grammar supported bydecodeand aLong object representing this value is returned.

      The second argument is the default value. ALong objectthat represents the value of the second argument is returned if thereis no property of the specified name, if the property does not havethe correct numeric format, or if the specified name is empty or null.

      In other words, this method returns aLong object equalto 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 aLong object whenthe default value is not needed.

      Parameters:
      nm - property name.
      val - default value.
      Returns:
      theLong value of the property.
      See Also:
    • getLong

      public static Long getLong(String nm,Long val)
      Returns thelong value of the system property withthe specified name. The first argument is treated as the nameof a system property. System properties are accessible throughtheSystem.getProperty(java.lang.String)method. The string value of this property is then interpretedas along value, as per thedecode method, and aLong objectrepresenting this value is returned; in summary:
      • If the property value begins with the two ASCII characters0x or the ASCII character#, not followed bya minus sign, then the rest of it is parsed as a hexadecimal integerexactly as for the methodvalueOf(java.lang.String, int)with radix 16.
      • If the property value begins with the ASCII character0 followed by another character, it is parsed asan octal integer exactly as by the methodvalueOf(java.lang.String, int) with radix 8.
      • Otherwise the property value is parsed as a decimalinteger exactly as by the methodvalueOf(java.lang.String, int) with radix 10.

      Note that, in every case, neitherL('\u004C') norl('\u006C') is permitted to appear at the endof the property value as a type indicator, as would bepermitted in Java programming language source code.

      The second argument is the default value. The default value isreturned if there is no property of the specified name, if theproperty does not have the correct numeric format, or if thespecified name is empty ornull.

      Parameters:
      nm - property name.
      val - default value.
      Returns:
      theLong value of the property.
      See Also:
    • compareTo

      public int compareTo(Long anotherLong)
      Compares twoLong objects numerically.
      Specified by:
      compareTo in interface Comparable<Long>
      Parameters:
      anotherLong - theLong to be compared.
      Returns:
      the value0 if thisLong is equal to the argumentLong; a value less than0 if thisLong is numerically less than the argumentLong; and a value greater than0 if thisLong is numerically greater than the argumentLong (signed comparison).
      Since:
      1.2
    • compare

      public static int compare(long x, long y)
      Compares twolong values numerically.The value returned is identical to what would be returned by:
         Long.valueOf(x).compareTo(Long.valueOf(y))
      Parameters:
      x - the firstlong to compare
      y - the secondlong to compare
      Returns:
      the value0 ifx == y; a value less than0 ifx < y; and a value greater than0 ifx > y
      Since:
      1.7
    • compareUnsigned

      public static int compareUnsigned(long x, long y)
      Compares twolong values numerically treating the valuesas unsigned.
      Parameters:
      x - the firstlong to compare
      y - the secondlong to compare
      Returns:
      the value0 ifx == y; a value less than0 ifx < y as unsigned values; and a value greater than0 ifx > 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 bythe second where each argument and the result is interpreted asan unsigned value.

      Note that in two's complement arithmetic, the three otherbasic arithmetic operations of add, subtract, and multiply arebit-wise identical if the two operands are regarded as bothbeing signed or both being unsigned. Therefore separateaddUnsigned, 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 bythe second argument
      Since:
      1.8
      See Also:
    • remainderUnsigned

      public static long remainderUnsigned(long dividend, long divisor)
      Returns the unsigned remainder from dividing the first argumentby the second where each argument and the result is interpretedas 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 bythe second argument
      Since:
      1.8
      See Also:
    • highestOneBit

      public static long highestOneBit(long i)
      Returns along value with at most a single one-bit, in theposition of the highest-order ("leftmost") one-bit in the specifiedlong value. Returns zero if the specified value has noone-bits in its two's complement binary representation, that is, if itis equal to zero.
      Parameters:
      i - the value whose highest one bit is to be computed
      Returns:
      along 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 along value with at most a single one-bit, in theposition of the lowest-order ("rightmost") one-bit in the specifiedlong value. Returns zero if the specified value has noone-bits in its two's complement binary representation, that is, if itis equal to zero.
      Parameters:
      i - the value whose lowest one bit is to be computed
      Returns:
      along 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 representationof the specifiedlong value. Returns 64 if thespecified 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 positivelong 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 specifiedlong 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 specifiedlong value. Returns 64 if the specified value has noone-bits in its two's complement representation, in other words if it isequal 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 specifiedlong 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 binaryrepresentation of the specifiedlong value. This function issometimes referred to as thepopulation 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 specifiedlong value.
      Since:
      1.5
    • rotateLeft

      public static long rotateLeft(long i, int distance)
      Returns the value obtained by rotating the two's complement binaryrepresentation of the specifiedlong value left by thespecified number of bits. (Bits shifted out of the left hand, orhigh-order, side reenter on the right, or low-order.)

      Note that left rotation with a negative distance is equivalent toright rotation:rotateLeft(val, -distance) == rotateRight(val,distance). Note also that rotation by any multiple of 64 is ano-op, so all but the last six bits of the rotation distance can beignored, 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 specifiedlong 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 binaryrepresentation of the specifiedlong value right by thespecified number of bits. (Bits shifted out of the right hand, orlow-order, side reenter on the left, or high-order.)

      Note that right rotation with a negative distance is equivalent toleft rotation:rotateRight(val, -distance) == rotateLeft(val,distance). Note also that rotation by any multiple of 64 is ano-op, so all but the last six bits of the rotation distance can beignored, 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 specifiedlong 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 thetwo's complement binary representation of the specifiedlongvalue.
      Parameters:
      i - the value to be reversed
      Returns:
      the value obtained by reversing order of the bits in the specifiedlong value.
      Since:
      1.5
    • compress

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

      For each one-bit valuemb of the mask, from leastsignificant to most significant, the bit value ofi atthe same bit location asmb is assigned to the compressedvalue contiguously starting from the least significant bit location.All the upper remaining bits of the compressed value are setto zero.

      API Note:
      Consider the simple case of compressing the digits of a hexadecimalvalue:
      // Compressing drink to foodcompress(0xCAFEBABEL, 0xFF00FFF0L) == 0xCABABL
      Starting from the least significant hexadecimal digit at position 0from the right, the mask0xFF00FFF0 selects hexadecimal digitsat positions 1, 2, 3, 6 and 7 of0xCAFEBABE. The selected digitsoccur in the resulting compressed value contiguously from digit position0 in the same order.

      The following identities all returntrue and are helpful tounderstand the behaviour ofcompress:

      // Returns 1 if the bit at position n is onecompress(x, 1L << n) == (x >> n & 1)// Logical shift rightcompress(x, -1L << n) == x >>> n// Any bits not covered by the mask are ignoredcompress(x, m) == compress(x & m, m)// Compressing a value by itselfcompress(m, m) == (m == -1 || m == 0) ? m : (1L << bitCount(m)) - 1// Expanding then compressing with the same maskcompress(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 goatssag(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

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

      For each one-bit valuemb of the mask, from leastsignificant to most significant, the next contiguous bit valueofi starting at the least significant bit is assignedto the expanded value at the same bit location asmb.All other remaining bits of the expanded value are set to zero.

      API Note:
      Consider the simple case of expanding the digits of a hexadecimalvalue:
      expand(0x0000CABABL, 0xFF00FFF0L) == 0xCA00BAB0L
      Starting from the least significant hexadecimal digit at position 0from the right, the mask0xFF00FFF0 selects the first fivehexadecimal digits of0x0000CABAB. The selected digits occurin the resulting expanded value in order at positions 1, 2, 3, 6, and 7.

      The following identities all returntrue and are helpful tounderstand the behaviour ofexpand:

      // Logically shift right the bit at position 0expand(x, 1L << n) == (x & 1) << n// Logically shift rightexpand(x, -1L << n) == x << n// Expanding all bits returns the maskexpand(-1L, m) == m// Any bits not covered by the mask are ignoredexpand(x, m) == expand(x, m) & m// Compressing then expanding with the same maskexpand(compress(x, m), m) == x & m

      The select operation for determining the position of the one-bit withindexn in along 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 1select(0b10101010_10101010, 0) == 1// The one-bit with index 3 is at bit position 7select(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:
    • signum

      public static int signum(long i)
      Returns the signum function of the specifiedlong value. (Thereturn value is -1 if the specified value is negative; 0 if thespecified 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 specifiedlong value.
      Since:
      1.5
    • reverseBytes

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

      public static long sum(long a, long b)
      Adds twolong values together as per the + operator.
      Parameters:
      a - the first operand
      b - the second operand
      Returns:
      the sum ofa andb
      Since:
      1.8
      See Also:
    • max

      public static long max(long a, long b)
      Returns the greater of twolong valuesas if by callingMath.max.
      Parameters:
      a - the first operand
      b - the second operand
      Returns:
      the greater ofa andb
      Since:
      1.8
      See Also:
    • min

      public static long min(long a, long b)
      Returns the smaller of twolong valuesas if by callingMath.min.
      Parameters:
      a - the first operand
      b - the second operand
      Returns:
      the smaller ofa andb
      Since:
      1.8
      See Also:
    • describeConstable

      public Optional<Long> describeConstable()
      Returns anOptional containing the nominal descriptor for thisinstance, which is the instance itself.
      Specified by:
      describeConstable in interface Constable
      Returns:
      anOptional describing theLong instance
      Since:
      12
    • resolveConstantDesc

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