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public final class

Long

extends Number
implements Comparable<T>
java.lang.Object
   ↳ java.lang.Number
     ↳ java.lang.Long

Class Overview

Long is the wrapper for the primitive type long.

As with the specification, this implementation relied on code laid out in Henry S. Warren, Jr.'s Hacker's Delight, (Addison Wesley, 2002) as well as The Aggregate's Magic Algorithms.

See Also

Summary

Constants
long MAX_VALUE

Constant for the maximum long value, 263-1.
long MIN_VALUE

Constant for the minimum long value, -231.
int SIZE

Constant for the number of bits to represent a long in two's compliment form.
Class<Long> TYPE The java.lang.Class that represents this class.
Public Constructors
Long(long value)
Constructs a new instance of the receiver which represents the long valued argument.
Long(String string)
Constructs a new instance of this class given a string.
Public Methods
static int bitCount(long lng)

Counts the number of 1 bits in the long value passed; this is sometimes referred to as a population count.

byte byteValue()
Returns the byte value which the receiver represents
int compareTo(Long object)

Compares this Long to the Long passed.

static Long decode(String string)
Parses the string argument as if it was a long value and returns the result.
double doubleValue()
Returns the double value which the receiver represents
boolean equals(Object o)
Compares the argument to the receiver, and returns true if they represent the same object using a class specific comparison.
float floatValue()
Returns the float value which the receiver represents
static Long getLong(String string, Long defaultValue)
Returns an Long representing the long value of the property named by the argument.
static Long getLong(String string, long defaultValue)
Returns a Long representing the long value of the property named by the argument.
static Long getLong(String string)
Returns a Long representing the long value of the property named by the argument.
int hashCode()
Returns an integer hash code for the receiver.
static long highestOneBit(long lng)

Determines the highest (leftmost) bit that is 1 and returns the value that is the bit mask for that bit.

int intValue()
Returns the int value which the receiver represents
long longValue()
Returns the long value which the receiver represents
static long lowestOneBit(long lng)

Determines the lowest (rightmost) bit that is 1 and returns the value that is the bit mask for that bit.

static int numberOfLeadingZeros(long lng)

Determines the number of leading zeros in the long passed prior to the highest one bit.

static int numberOfTrailingZeros(long lng)

Determines the number of trailing zeros in the long passed after the lowest one bit.

static long parseLong(String string, int radix)
Parses the string argument as if it was an long value and returns the result.
static long parseLong(String string)
Parses the string argument as if it was a long value and returns the result.
static long reverse(long lng)

Reverses the bytes of a long.

static long reverseBytes(long lng)

Reverses the bytes of a long.

static long rotateLeft(long lng, int distance)

Rotates the bits of lng to the left by the distance bits.

static long rotateRight(long lng, int distance)

Rotates the bits of lng to the right by the distance bits.

short shortValue()
Returns the short value which the receiver represents
static int signum(long lng)

The signum function for long values.

static String toBinaryString(long l)
Returns a string containing '0' and '1' characters which describe the binary representation of the argument.
static String toHexString(long l)
Returns a string containing characters in the range 0..7, a..f which describe the hexadecimal representation of the argument.
static String toOctalString(long l)
Returns a string containing characters in the range 0..7 which describe the octal representation of the argument.
static String toString(long l, int radix)
Returns a string containing characters in the range 0..9, a..z (depending on the radix) which describe the representation of the argument in that radix.
String toString()
Returns a string containing a concise, human-readable description of the receiver.
static String toString(long l)
Returns a string containing characters in the range 0..9 which describe the decimal representation of the argument.
static Long valueOf(String string, int radix)
Parses the string argument as if it was an long value and returns the result.
static Long valueOf(String string)
Parses the string argument as if it was an long value and returns the result.
static Long valueOf(long lng)

Returns a Long instance for the long value passed.

[Expand]
Inherited Methods
From class java.lang.Number
From class java.lang.Object
From interface java.lang.Comparable

Constants

public static final long MAX_VALUE

Constant for the maximum long value, 263-1.

Constant Value: 9223372036854775807 (0x7fffffffffffffff)

public static final long MIN_VALUE

Constant for the minimum long value, -231.

Constant Value: -9223372036854775808 (0x8000000000000000)

public static final int SIZE

Constant for the number of bits to represent a long in two's compliment form.

Constant Value: 64 (0x00000040)

public static final Class<Long> TYPE

The java.lang.Class that represents this class.

Public Constructors

public Long (long value)

Constructs a new instance of the receiver which represents the long valued argument.

Parameters
value the long to store in the new instance.

public Long (String string)

Constructs a new instance of this class given a string.

Parameters
string a string representation of an long quantity.
Throws
NumberFormatException if the argument could not be parsed as a long quantity.

Public Methods

public static int bitCount (long lng)

Counts the number of 1 bits in the long value passed; this is sometimes referred to as a population count.

Parameters
lng The long value to process.
Returns
  • The number of 1 bits.

public byte byteValue ()

Returns the byte value which the receiver represents

Returns
  • byte the value of the receiver.

public int compareTo (Long object)

Compares this Long to the Long passed. If this instance's value is equal to the value of the instance passed, then 0 is returned. If this instance's value is less than the value of the instance passed, then a negative value is returned. If this instance's value is greater than the value of the instance passed, then a positive value is returned.

Parameters
object The instance to compare to.
Throws
NullPointerException if object is null.

public static Long decode (String string)

Parses the string argument as if it was a long value and returns the result. Throws NumberFormatException if the string does not represent a long quantity. The string may be a hexadecimal ("0x..."), octal ("0..."), or decimal ("...") representation of a long.

Parameters
string a string representation of an long quantity.
Returns
  • Long the value represented by the argument
Throws
NumberFormatException if the argument could not be parsed as an long quantity.

public double doubleValue ()

Returns the double value which the receiver represents

Returns
  • double the value of the receiver.

public boolean equals (Object o)

Compares the argument to the receiver, and returns true if they represent the same object using a class specific comparison.

In this case, the argument must also be an Long, and the receiver and argument must represent the same long value.

Parameters
o the object to compare with this object
Returns
  • true if the object is the same as this object false if it is different from this object
See Also

public float floatValue ()

Returns the float value which the receiver represents

Returns
  • float the value of the receiver.

public static Long getLong (String string, Long defaultValue)

Returns an Long representing the long value of the property named by the argument. If the property could not be found, or its value could not be parsed as an long, answer the second argument.

Parameters
string The name of the desired long property.
Returns
  • Long An Long representing the value of the property.

public static Long getLong (String string, long defaultValue)

Returns a Long representing the long value of the property named by the argument. If the property could not be found, or its value could not be parsed as a long, answer a Long representing the second argument.

Parameters
string The name of the desired long property.
Returns
  • Long An Long representing the value of the property.

public static Long getLong (String string)

Returns a Long representing the long value of the property named by the argument. If the property could not be found, or its value could not be parsed as a long, answer null.

Parameters
string The name of the desired integer property.
Returns
  • Long A Long representing the value of the property.

public int hashCode ()

Returns an integer hash code for the receiver. Any two objects which answer true when passed to equals must answer the same value for this method.

Returns
  • the receiver's hash
See Also

public static long highestOneBit (long lng)

Determines the highest (leftmost) bit that is 1 and returns the value that is the bit mask for that bit. This is sometimes referred to as the Most Significant 1 Bit.

Parameters
lng The long to interrogate.
Returns
  • The bit mask indicating the highest 1 bit.

public int intValue ()

Returns the int value which the receiver represents

Returns
  • int the value of the receiver.

public long longValue ()

Returns the long value which the receiver represents

Returns
  • long the value of the receiver.

public static long lowestOneBit (long lng)

Determines the lowest (rightmost) bit that is 1 and returns the value that is the bit mask for that bit. This is sometimes referred to as the Least Significant 1 Bit.

Parameters
lng The long to interrogate.
Returns
  • The bit mask indicating the lowest 1 bit.

public static int numberOfLeadingZeros (long lng)

Determines the number of leading zeros in the long passed prior to the highest one bit.

Parameters
lng The long to process.
Returns
  • The number of leading zeros.

public static int numberOfTrailingZeros (long lng)

Determines the number of trailing zeros in the long passed after the lowest one bit.

Parameters
lng The long to process.
Returns
  • The number of trailing zeros.

public static long parseLong (String string, int radix)

Parses the string argument as if it was an long value and returns the result. Throws NumberFormatException if the string does not represent an long quantity. The second argument specifies the radix to use when parsing the value.

Parameters
string a string representation of an long quantity.
radix the base to use for conversion.
Returns
  • long the value represented by the argument
Throws
NumberFormatException if the argument could not be parsed as an long quantity.

public static long parseLong (String string)

Parses the string argument as if it was a long value and returns the result. Throws NumberFormatException if the string does not represent a long quantity.

Parameters
string a string representation of a long quantity.
Returns
  • long the value represented by the argument
Throws
NumberFormatException if the argument could not be parsed as a long quantity.

public static long reverse (long lng)

Reverses the bytes of a long.

Parameters
lng The long to reverse.
Returns
  • The reversed value.

public static long reverseBytes (long lng)

Reverses the bytes of a long.

Parameters
lng The long to reverse.
Returns
  • The reversed value.

public static long rotateLeft (long lng, int distance)

Rotates the bits of lng to the left by the distance bits.

Parameters
lng The long value to rotate left.
distance The number of bits to rotate.
Returns
  • The rotated value.

public static long rotateRight (long lng, int distance)

Rotates the bits of lng to the right by the distance bits.

Parameters
lng The long value to rotate right.
distance The number of bits to rotate.
Returns
  • The rotated value.

public short shortValue ()

Returns the short value which the receiver represents

Returns
  • short the value of the receiver.

public static int signum (long lng)

The signum function for long values. This method returns -1 for negative values, 1 for positive values and 0 for the value 0.

Parameters
lng The long value.
Returns
  • -1 if negative, 1 if positive otherwise 0.

public static String toBinaryString (long l)

Returns a string containing '0' and '1' characters which describe the binary representation of the argument.

Parameters
l a long to get the binary representation of
Returns
  • String the binary representation of the argument

public static String toHexString (long l)

Returns a string containing characters in the range 0..7, a..f which describe the hexadecimal representation of the argument.

Parameters
l a long to get the hex representation of
Returns
  • String the hex representation of the argument

public static String toOctalString (long l)

Returns a string containing characters in the range 0..7 which describe the octal representation of the argument.

Parameters
l a long to get the octal representation of
Returns
  • String the octal representation of the argument

public static String toString (long l, int radix)

Returns a string containing characters in the range 0..9, a..z (depending on the radix) which describe the representation of the argument in that radix.

Parameters
l a long to get the representation of
radix the base to use for conversion.
Returns
  • String the representation of the argument

public String toString ()

Returns a string containing a concise, human-readable description of the receiver.

Returns
  • a printable representation for the receiver.

public static String toString (long l)

Returns a string containing characters in the range 0..9 which describe the decimal representation of the argument.

Parameters
l a long to get the representation of
Returns
  • String the representation of the argument

public static Long valueOf (String string, int radix)

Parses the string argument as if it was an long value and returns the result. Throws NumberFormatException if the string does not represent an long quantity. The second argument specifies the radix to use when parsing the value.

Parameters
string a string representation of an long quantity.
radix the base to use for conversion.
Returns
  • Long the value represented by the argument
Throws
NumberFormatException if the argument could not be parsed as an long quantity.

public static Long valueOf (String string)

Parses the string argument as if it was an long value and returns the result. Throws NumberFormatException if the string does not represent an long quantity.

Parameters
string a string representation of an long quantity.
Returns
  • Long the value represented by the argument
Throws
NumberFormatException if the argument could not be parsed as an long quantity.

public static Long valueOf (long lng)

Returns a Long instance for the long value passed. This method is preferred over the constructor, as this method may maintain a cache of instances.

Parameters
lng The long value.
Returns
  • A Long instance.