Field Summary

Constructor Summary

Method Summary

Field Details

• MIN_VALUE

  @Nativepublic static final long MIN_VALUE

  A constant holding the minimum value along can have, -2⁶³.

  See Also:

  • Constant Field Values

• MAX_VALUE

  @Nativepublic static final long MAX_VALUE

  A constant holding the maximum value along can have, 2⁶³-1.

  See Also:

  • Constant Field Values

• 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'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 along value in two's complement binary form.

  Since:

  1.8

  See Also:

  • Constant Field Values

Constructor Details

• Long

  @Deprecated(since="9",forRemoval=true)public Long(long value)

  Deprecated, for removal: This API element is subject to removal in a future version.

  It is rarely appropriate to use this constructor. The static factoryvalueOf(long) is generally a better choice, as it is likely to yield significantly better space and time performance.

  Constructs a newly allocatedLong object that represents the specifiedlong argument.

  Parameters:

  value - the value to be represented by theLong object.

• Long

  @Deprecated(since="9",forRemoval=true)public Long(String s) throwsNumberFormatException

  Deprecated, for removal: This API element is subject to removal in a future version.

  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 that represents 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 the radix specified by the second argument.

  If the radix is smaller thanCharacter.MIN_RADIX or larger thanCharacter.MAX_RADIX, then the radix10 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'. Ifradix isN, then the firstN of these characters are used as radix-N digits in the order shown. Thus, the digits for hexadecimal (radix 16) are0123456789abcdef. If uppercase letters are desired, theString.toUpperCase() method may be 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:

  • 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 thanCharacter.MIN_RADIX or larger thanCharacter.MAX_RADIX, then the radix10 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 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:

  • toString(long, int)

• toHexString

  public static String toHexString(long i)

  Returns a string representation of thelong argument as an unsigned integer in base 16.

  The unsignedlong 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 leading0s.

  The value of the argument can be recovered from the returned strings by callingLong.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, theString.toUpperCase() method may be called on the result:

  Long.toHexString(n).toUpperCase()

  API Note:

  TheHexFormat class provides formatting and parsing of 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 byte a 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:

  • HexFormat
  • parseUnsignedLong(String, int)
  • toUnsignedString(long, int)

• toOctalString

  public static String toOctalString(long i)

  Returns a string representation of thelong argument as an unsigned integer in base 8.

  The unsignedlong 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 leading0s.

  The value of the argument can be recovered from the returned strings by callingLong.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 - 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:

  • parseUnsignedLong(String, int)
  • toUnsignedString(long, int)

• toBinaryString

  public static String toBinaryString(long i)

  Returns a string representation of thelong argument as an unsigned integer in base 2.

  The unsignedlong 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 leading0s.

  The value of the argument can be recovered from the returned strings by callingLong.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 - 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:

  • parseUnsignedLong(String, int)
  • toUnsignedString(long, int)

• toString

  public static String toString(long i)

  Returns aString object representing the specifiedlong. 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 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 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 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:

  • toUnsignedString(long, int)

• parseLong

  public static long parseLong(String s, int radix) throwsNumberFormatException

  Parses the string argument as a signedlong in the radix specified by the second argument. The characters in the string must all be digits of the specified radix (as determined by whetherCharacter.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 resultinglong value is returned.

  Note that neither the characterL ('\u004C') norl ('\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 eitherL orl may appear as a digit for a radix greater than or equal to 22.

  An exception of typeNumberFormatException is thrown if any of the following situations occurs:

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

  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 - 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 in the 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, 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 resultinglong value is returned, exactly as if the argument and the radix10 were given as arguments to theparseLong(java.lang.String, int) method.

  Note that neither the characterL ('\u004C') norl ('\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 - 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 the radix specified by the second argument. An unsigned integer maps the values usually associated with negative numbers to positive numbers larger thanMAX_VALUE. The characters in the string must all be digits of the specified radix (as determined by whetherCharacter.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 typeNumberFormatException is thrown if any of the following situations occurs:

  • The first argument isnull or is a string of length zero.
  • The radix is either smaller thanCharacter.MIN_RADIX or larger thanCharacter.MAX_RADIX.
  • Any character of the string is not a digit of the specified radix, except that the first character may be a plus sign'+' ('\u002B') provided that the string is longer than length 1.
  • The value represented by the string is larger than the largest 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 in the 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. 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 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 value extracted from the specifiedString when parsed with the radix given by the second argument. The first argument is interpreted as representing a signedlong in the radix specified by the second argument, exactly as if the arguments were given to theparseLong(java.lang.String, int) method. The result is aLong object that represents thelong value specified by the string.

  In other words, this method returns aLong 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 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 value of the specifiedString. The argument is interpreted 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 value specified by the string.

  In other words, this method returns aLong object equal 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 method should generally be used in preference to the constructorLong(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:

  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 the following grammar:

  DecodableString:

  Sign_opt DecimalNumeral

  Sign_opt0xHexDigits

  Sign_opt0XHexDigits

  Sign_opt#HexDigits

  Sign_opt0OctalDigits

  Sign:

  -

  +

  DecimalNumeral,HexDigits, andOctalDigits are as defined in section3.10.1 ofThe 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 aNumberFormatException will be thrown. The result is negated if first character of the specifiedString is the 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:

  • parseLong(String, int)

• byteValue

  public byte byteValue()

  Returns the value of thisLong as abyte after a 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 after a 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 after a 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 after a 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 adouble after 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 signed decimal representation and returned as a string, exactly as if thelong 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 is the exclusive OR of the two halves of the primitivelong value held by thisLong 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(java.lang.Object)

• 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 that contains 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:

  • Object.hashCode()
  • HashMap

• getLong

  public static Long getLong(String nm)

  Determines thelong 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 theSystem.getProperty(java.lang.String) method. The string value of this property is then interpreted as a long value using the grammar supported bydecode and aLong object representing this value is returned.

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

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

  getLong(nm, null)

  Parameters:

  nm - property name.

  Returns:

  theLong 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 thelong 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 theSystem.getProperty(java.lang.String) method. The string value of this property is then interpreted as a long value using the grammar supported bydecode and aLong object representing this value is returned.

  The second argument is the default value. ALong 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 aLong 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 aLong object when the default value is not needed.

  Parameters:

  nm - property name.

  val - default value.

  Returns:

  theLong 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 thelong 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 theSystem.getProperty(java.lang.String) method. The string value of this property is then interpreted as along value, as per thedecode method, and aLong object representing this value is returned; in summary:

  • If the property value begins with the two ASCII characters0x 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 methodvalueOf(java.lang.String, int) with radix 16.
  • If the property value begins with the ASCII character0 followed by another character, it is parsed as an octal integer exactly as by the methodvalueOf(java.lang.String, int) with radix 8.
  • Otherwise the property value is parsed as a decimal integer exactly as by the methodvalueOf(java.lang.String, int) with radix 10.

  Note that, in every case, neitherL ('\u004C') norl ('\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 ornull.

  Parameters:

  nm - property name.

  val - default value.

  Returns:

  theLong 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 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 values as 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 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 along value with at most a single one-bit, in the position of the highest-order ("leftmost") one-bit in the specifiedlong 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:

  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 the position of the lowest-order ("rightmost") one-bit in the specifiedlong 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:

  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 representation of the specifiedlong 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 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 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 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 binary representation of the specifiedlong value. This function is sometimes 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 binary representation of the specifiedlong 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 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 binary representation of the specifiedlong 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 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 the two's complement binary representation of the specifiedlong value.

  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 the specifiedlong value,i, in accordance with the specified bit mask.

  For each one-bit valuemb of the mask, from least significant to most significant, the bit value ofi at the same bit location asmb 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:

  Copy

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

  Starting from the least significant hexadecimal digit at position 0 from the right, the mask0xFF00FFF0 selects hexadecimal digits at positions 1, 2, 3, 6 and 7 of0xCAFEBABE. The selected digits occur in the resulting compressed value contiguously from digit position 0 in the same order.

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

  Copy

  // 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:

  Copy

  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(long, long)

• expand

  public static long expand(long i, long mask)

  Returns the value obtained by expanding the bits of the specifiedlong value,i, in accordance with the specified bit mask.

  For each one-bit valuemb of the mask, from least significant to most significant, the next contiguous bit value ofi starting at the least significant bit is assigned to 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 hexadecimal value:

  Copy

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

  Starting from the least significant hexadecimal digit at position 0 from the right, the mask0xFF00FFF0 selects the first five hexadecimal digits of0x0000CABAB. The selected digits occur in the resulting expanded value in order at positions 1, 2, 3, 6, and 7.

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

  Copy

  // 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 with indexn in along value can be implemented as follows:

  Copy

  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:

  • compress(long, long)

• signum

  public static int signum(long i)

  Returns the signum function of the specifiedlong 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 specifiedlong 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 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:

  • BinaryOperator

• max

  public static long max(long a, long b)

  Returns the greater of twolong values as if by callingMath.max.

  Parameters:

  a - the first operand

  b - the second operand

  Returns:

  the greater ofa andb

  Since:

  1.8

  See Also:

  • BinaryOperator

• min

  public static long min(long a, long b)

  Returns the smaller of twolong values as if by callingMath.min.

  Parameters:

  a - the first operand

  b - the second operand

  Returns:

  the smaller ofa andb

  Since:

  1.8

  See Also:

  • BinaryOperator

• describeConstable

  public Optional<Long> describeConstable()

  Returns anOptional containing the nominal descriptor for this instance, 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 is the instance itself.

  Specified by:

  resolveConstantDesc in interface ConstantDesc

  Parameters:

  lookup - ignored

  Returns:

  theLong instance

  Since:

  12