| Methods Summary |
|---|
| public static int | bitCount(long i)Returns the number of one-bits in the two's complement binary
representation of the specified long value. This function is
sometimes referred to as the population count.
// HD, Figure 5-14
i = i - ((i >>> 1) & 0x5555555555555555L);
i = (i & 0x3333333333333333L) + ((i >>> 2) & 0x3333333333333333L);
i = (i + (i >>> 4)) & 0x0f0f0f0f0f0f0f0fL;
i = i + (i >>> 8);
i = i + (i >>> 16);
i = i + (i >>> 32);
return (int)i & 0x7f;
|
| public byte | byteValue()Returns the value of this Long as a
byte.
return (byte)value;
|
| public int | compareTo(java.lang.Long anotherLong)Compares two Long objects numerically.
long thisVal = this.value;
long anotherVal = anotherLong.value;
return (thisVal<anotherVal ? -1 : (thisVal==anotherVal ? 0 : 1));
|
| public static java.lang.Long | decode(java.lang.String nm)Decodes a String into a Long.
Accepts decimal, hexadecimal, and octal numbers given by the
following grammar:
- DecodableString:
- Signopt DecimalNumeral
- Signopt
0x HexDigits
- Signopt
0X HexDigits
- Signopt
# HexDigits
- Signopt
0 OctalDigits
- Sign:
-
DecimalNumeral, HexDigits, and OctalDigits
are defined in §3.10.1
of the Java
Language Specification.
The sequence of characters following an (optional) negative
sign and/or radix specifier ("0x",
"0X", "#", or
leading zero) is parsed as by the Long.parseLong
method with the indicated radix (10, 16, or 8). This sequence
of characters must represent a positive value or a {@link
NumberFormatException} will be thrown. The result is negated
if first character of the specified String is the
minus sign. No whitespace characters are permitted in the
String.
int radix = 10;
int index = 0;
boolean negative = false;
Long result;
// Handle minus sign, if present
if (nm.startsWith("-")) {
negative = true;
index++;
}
// Handle radix specifier, if present
if (nm.startsWith("0x", index) || nm.startsWith("0X", index)) {
index += 2;
radix = 16;
}
else if (nm.startsWith("#", index)) {
index ++;
radix = 16;
}
else if (nm.startsWith("0", index) && nm.length() > 1 + index) {
index ++;
radix = 8;
}
if (nm.startsWith("-", index))
throw new NumberFormatException("Negative sign in wrong position");
try {
result = Long.valueOf(nm.substring(index), radix);
result = negative ? new Long((long)-result.longValue()) : result;
} catch (NumberFormatException e) {
// If number is Long.MIN_VALUE, we'll end up here. The next line
// handles this case, and causes any genuine format error to be
// rethrown.
String constant = negative ? new String("-" + nm.substring(index))
: nm.substring(index);
result = Long.valueOf(constant, radix);
}
return result;
|
| public double | doubleValue()Returns the value of this Long as a
double.
return (double)value;
|
| public boolean | equals(java.lang.Object obj)Compares this object to the specified object. The result is
true if and only if the argument is not
null and is a Long object that
contains the same long value as this object.
if (obj instanceof Long) {
return value == ((Long)obj).longValue();
}
return false;
|
| public float | floatValue()Returns the value of this Long as a
float.
return (float)value;
|
| static void | getChars(long i, int index, char[] buf)Places characters representing the integer i into the
character array buf. The characters are placed into
the buffer backwards starting with the least significant
digit at the specified index (exclusive), and working
backwards from there.
Will fail if i == Long.MIN_VALUE
long q;
int r;
int charPos = index;
char sign = 0;
if (i < 0) {
sign = '-";
i = -i;
}
// Get 2 digits/iteration using longs until quotient fits into an int
while (i > Integer.MAX_VALUE) {
q = i / 100;
// really: r = i - (q * 100);
r = (int)(i - ((q << 6) + (q << 5) + (q << 2)));
i = q;
buf[--charPos] = Integer.DigitOnes[r];
buf[--charPos] = Integer.DigitTens[r];
}
// Get 2 digits/iteration using ints
int q2;
int i2 = (int)i;
while (i2 >= 65536) {
q2 = i2 / 100;
// really: r = i2 - (q * 100);
r = i2 - ((q2 << 6) + (q2 << 5) + (q2 << 2));
i2 = q2;
buf[--charPos] = Integer.DigitOnes[r];
buf[--charPos] = Integer.DigitTens[r];
}
// Fall thru to fast mode for smaller numbers
// assert(i2 <= 65536, i2);
for (;;) {
q2 = (i2 * 52429) >>> (16+3);
r = i2 - ((q2 << 3) + (q2 << 1)); // r = i2-(q2*10) ...
buf[--charPos] = Integer.digits[r];
i2 = q2;
if (i2 == 0) break;
}
if (sign != 0) {
buf[--charPos] = sign;
}
|
| public static java.lang.Long | getLong(java.lang.String nm)Determines the long value of the system property
with the specified name.
The first argument is treated as the name of a system property.
System properties are accessible through the {@link
java.lang.System#getProperty(java.lang.String)} method. The
string value of this property is then interpreted as a
long value and a Long object
representing this value is returned. Details of possible
numeric formats can be found with the definition of
getProperty.
If there is no property with the specified name, if the
specified name is empty or null, or if the
property does not have the correct numeric format, then
null is returned.
In other words, this method returns a Long object equal to
the value of:
getLong(nm, null)
return getLong(nm, null);
|
| public static java.lang.Long | getLong(java.lang.String nm, long val)Determines the long value of the system property
with the specified name.
The first argument is treated as the name of a system property.
System properties are accessible through the {@link
java.lang.System#getProperty(java.lang.String)} method. The
string value of this property is then interpreted as a
long value and a Long object
representing this value is returned. Details of possible
numeric formats can be found with the definition of
getProperty.
The second argument is the default value. A Long object
that represents the value of the second argument is returned if there
is no property of the specified name, if the property does not have
the correct numeric format, or if the specified name is empty or null.
In other words, this method returns a Long object equal
to the value of:
getLong(nm, new Long(val))
but in practice it may be implemented in a manner such as:
Long result = getLong(nm, null);
return (result == null) ? new Long(val) : result;
to avoid the unnecessary allocation of a Long object when
the default value is not needed.
Long result = Long.getLong(nm, null);
return (result == null) ? new Long(val) : result;
|
| public static java.lang.Long | getLong(java.lang.String nm, java.lang.Long val)Returns the long value of the system property with
the specified name. The first argument is treated as the name
of a system property. System properties are accessible through
the {@link java.lang.System#getProperty(java.lang.String)}
method. The string value of this property is then interpreted
as a long value, as per the
Long.decode method, and a Long object
representing this value is returned.
- If the property value begins with the two ASCII characters
0x or the ASCII character #, not followed by
a minus sign, then the rest of it is parsed as a hexadecimal integer
exactly as for the method {@link #valueOf(java.lang.String, int)}
with radix 16.
- If the property value begins with the ASCII character
0 followed by another character, it is parsed as
an octal integer exactly as by the method {@link
#valueOf(java.lang.String, int)} with radix 8.
- Otherwise the property value is parsed as a decimal
integer exactly as by the method
{@link #valueOf(java.lang.String, int)} with radix 10.
Note that, in every case, neither L
('\u004C') nor l
('\u006C') is permitted to appear at the end
of the property value as a type indicator, as would be
permitted in Java programming language source code.
The second argument is the default value. The default value is
returned if there is no property of the specified name, if the
property does not have the correct numeric format, or if the
specified name is empty or null.
String v = null;
try {
v = System.getProperty(nm);
} catch (IllegalArgumentException e) {
} catch (NullPointerException e) {
}
if (v != null) {
try {
return Long.decode(v);
} catch (NumberFormatException e) {
}
}
return val;
|
| public int | hashCode()Returns a hash code for this Long. The result is
the exclusive OR of the two halves of the primitive
long value held by this Long
object. That is, the hashcode is the value of the expression:
(int)(this.longValue()^(this.longValue()>>>32))
return (int)(value ^ (value >>> 32));
|
| public static long | highestOneBit(long i)Returns a long value with at most a single one-bit, in the
position of the highest-order ("leftmost") one-bit in the specified
long value. Returns zero if the specified value has no
one-bits in its two's complement binary representation, that is, if it
is equal to zero.
// HD, Figure 3-1
i |= (i >> 1);
i |= (i >> 2);
i |= (i >> 4);
i |= (i >> 8);
i |= (i >> 16);
i |= (i >> 32);
return i - (i >>> 1);
|
| public int | intValue()Returns the value of this Long as an
int.
return (int)value;
|
| public long | longValue()Returns the value of this Long as a
long value.
return (long)value;
|
| public static long | lowestOneBit(long i)Returns a long value with at most a single one-bit, in the
position of the lowest-order ("rightmost") one-bit in the specified
long value. Returns zero if the specified value has no
one-bits in its two's complement binary representation, that is, if it
is equal to zero.
// HD, Section 2-1
return i & -i;
|
| public static int | numberOfLeadingZeros(long i)Returns the number of zero bits preceding the highest-order
("leftmost") one-bit in the two's complement binary representation
of the specified long value. Returns 64 if the
specified value has no one-bits in its two's complement representation,
in other words if it is equal to zero.
Note that this method is closely related to the logarithm base 2.
For all positive long values x:
- floor(log2(x)) = 63 - numberOfLeadingZeros(x)
- ceil(log2(x)) = 64 - numberOfLeadingZeros(x - 1)
// HD, Figure 5-6
if (i == 0)
return 64;
int n = 1;
int x = (int)(i >>> 32);
if (x == 0) { n += 32; x = (int)i; }
if (x >>> 16 == 0) { n += 16; x <<= 16; }
if (x >>> 24 == 0) { n += 8; x <<= 8; }
if (x >>> 28 == 0) { n += 4; x <<= 4; }
if (x >>> 30 == 0) { n += 2; x <<= 2; }
n -= x >>> 31;
return n;
|
| public static int | numberOfTrailingZeros(long i)Returns the number of zero bits following the lowest-order ("rightmost")
one-bit in the two's complement binary representation of the specified
long value. Returns 64 if the specified value has no
one-bits in its two's complement representation, in other words if it is
equal to zero.
// HD, Figure 5-14
int x, y;
if (i == 0) return 64;
int n = 63;
y = (int)i; if (y != 0) { n = n -32; x = y; } else x = (int)(i>>>32);
y = x <<16; if (y != 0) { n = n -16; x = y; }
y = x << 8; if (y != 0) { n = n - 8; x = y; }
y = x << 4; if (y != 0) { n = n - 4; x = y; }
y = x << 2; if (y != 0) { n = n - 2; x = y; }
return n - ((x << 1) >>> 31);
|
| public static long | parseLong(java.lang.String s)Parses the string argument as a signed decimal
long. The characters in the string must all be
decimal digits, except that the first character may be an ASCII
minus sign '-' (\u002D') to
indicate a negative value. The resulting long
value is returned, exactly as if the argument and the radix
10 were given as arguments to the {@link
#parseLong(java.lang.String, int)} method.
Note that neither the character L
('\u004C') nor l
('\u006C') is permitted to appear at the end
of the string as a type indicator, as would be permitted in
Java programming language source code.
return parseLong(s, 10);
|
| public static long | parseLong(java.lang.String s, int radix)Parses the string argument as a signed long in the
radix specified by the second argument. The characters in the
string must all be digits of the specified radix (as determined
by whether {@link java.lang.Character#digit(char, int)} returns
a nonnegative value), except that the first character may be an
ASCII minus sign '-' ('\u002D') to
indicate a negative value. The resulting long
value is returned.
Note that neither the character L
('\u004C') nor l
('\u006C') is permitted to appear at the end
of the string as a type indicator, as would be permitted in
Java programming language source code - except that either
L or l may appear as a digit for a
radix greater than 22.
An exception of type NumberFormatException is
thrown if any of the following situations occurs:
- The first argument is
null or is a string of
length zero.
- The
radix is either smaller than {@link
java.lang.Character#MIN_RADIX} or larger than {@link
java.lang.Character#MAX_RADIX}.
- Any character of the string is not a digit of the specified
radix, except that the first character may be a minus sign
'-' ('\u002d') provided that the
string is longer than length 1.
- The value represented by the string is not a value of type
long.
Examples:
parseLong("0", 10) returns 0L
parseLong("473", 10) returns 473L
parseLong("-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
if (s == null) {
throw new NumberFormatException("null");
}
if (radix < Character.MIN_RADIX) {
throw new NumberFormatException("radix " + radix +
" less than Character.MIN_RADIX");
}
if (radix > Character.MAX_RADIX) {
throw new NumberFormatException("radix " + radix +
" greater than Character.MAX_RADIX");
}
long result = 0;
boolean negative = false;
int i = 0, max = s.length();
long limit;
long multmin;
int digit;
if (max > 0) {
if (s.charAt(0) == '-") {
negative = true;
limit = Long.MIN_VALUE;
i++;
} else {
limit = -Long.MAX_VALUE;
}
multmin = limit / radix;
if (i < max) {
digit = Character.digit(s.charAt(i++),radix);
if (digit < 0) {
throw NumberFormatException.forInputString(s);
} else {
result = -digit;
}
}
while (i < max) {
// Accumulating negatively avoids surprises near MAX_VALUE
digit = Character.digit(s.charAt(i++),radix);
if (digit < 0) {
throw NumberFormatException.forInputString(s);
}
if (result < multmin) {
throw NumberFormatException.forInputString(s);
}
result *= radix;
if (result < limit + digit) {
throw NumberFormatException.forInputString(s);
}
result -= digit;
}
} else {
throw NumberFormatException.forInputString(s);
}
if (negative) {
if (i > 1) {
return result;
} else { /* Only got "-" */
throw NumberFormatException.forInputString(s);
}
} else {
return -result;
}
|
| public static long | reverse(long i)Returns the value obtained by reversing the order of the bits in the
two's complement binary representation of the specified long
value.
// HD, Figure 7-1
i = (i & 0x5555555555555555L) << 1 | (i >>> 1) & 0x5555555555555555L;
i = (i & 0x3333333333333333L) << 2 | (i >>> 2) & 0x3333333333333333L;
i = (i & 0x0f0f0f0f0f0f0f0fL) << 4 | (i >>> 4) & 0x0f0f0f0f0f0f0f0fL;
i = (i & 0x00ff00ff00ff00ffL) << 8 | (i >>> 8) & 0x00ff00ff00ff00ffL;
i = (i << 48) | ((i & 0xffff0000L) << 16) |
((i >>> 16) & 0xffff0000L) | (i >>> 48);
return i;
|
| public static long | reverseBytes(long i)Returns the value obtained by reversing the order of the bytes in the
two's complement representation of the specified long value.
i = (i & 0x00ff00ff00ff00ffL) << 8 | (i >>> 8) & 0x00ff00ff00ff00ffL;
return (i << 48) | ((i & 0xffff0000L) << 16) |
((i >>> 16) & 0xffff0000L) | (i >>> 48);
|
| public static long | rotateLeft(long i, int distance)Returns the value obtained by rotating the two's complement binary
representation of the specified long value left by the
specified number of bits. (Bits shifted out of the left hand, or
high-order, side reenter on the right, or low-order.)
Note that left rotation with a negative distance is equivalent to
right rotation: rotateLeft(val, -distance) == rotateRight(val,
distance). Note also that rotation by any multiple of 64 is a
no-op, so all but the last six bits of the rotation distance can be
ignored, even if the distance is negative: rotateLeft(val,
distance) == rotateLeft(val, distance & 0x3F).
return (i << distance) | (i >>> -distance);
|
| public static long | rotateRight(long i, int distance)Returns the value obtained by rotating the two's complement binary
representation of the specified long value right by the
specified number of bits. (Bits shifted out of the right hand, or
low-order, side reenter on the left, or high-order.)
Note that right rotation with a negative distance is equivalent to
left rotation: rotateRight(val, -distance) == rotateLeft(val,
distance). Note also that rotation by any multiple of 64 is a
no-op, so all but the last six bits of the rotation distance can be
ignored, even if the distance is negative: rotateRight(val,
distance) == rotateRight(val, distance & 0x3F).
return (i >>> distance) | (i << -distance);
|
| public short | shortValue()Returns the value of this Long as a
short.
return (short)value;
|
| public static int | signum(long i)Returns the signum function of the specified long value. (The
return value is -1 if the specified value is negative; 0 if the
specified value is zero; and 1 if the specified value is positive.)
// HD, Section 2-7
return (int) ((i >> 63) | (-i >>> 63));
|
| static int | stringSize(long x)
long p = 10;
for (int i=1; i<19; i++) {
if (x < p)
return i;
p = 10*p;
}
return 19;
|
| public static java.lang.String | toBinaryString(long i)Returns a string representation of the long
argument as an unsigned integer in base 2.
The unsigned long value is the argument plus
264 if the argument is negative; otherwise, it is
equal to the argument. This value is converted to a string of
ASCII digits in binary (base 2) with no extra leading
0s. 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.
return toUnsignedString(i, 1);
|
| public static java.lang.String | toHexString(long i)Returns a string representation of the long
argument as an unsigned integer in base 16.
The unsigned long value is the argument plus
264 if the argument is negative; otherwise, it is
equal to the argument. This value is converted to a string of
ASCII digits in hexadecimal (base 16) with no extra
leading 0s. If the unsigned magnitude is zero, it
is represented by a single zero character '0'
('\u0030'); otherwise, the first character of
the representation of the unsigned magnitude will not be the
zero character. The following characters are used as
hexadecimal digits:
0123456789abcdef
These are the characters '\u0030' through
'\u0039' and '\u0061' through
'\u0066'. If uppercase letters are desired,
the {@link java.lang.String#toUpperCase()} method may be called
on the result:
Long.toHexString(n).toUpperCase()
return toUnsignedString(i, 4);
|
| public static java.lang.String | toOctalString(long i)Returns a string representation of the long
argument as an unsigned integer in base 8.
The unsigned long value is the argument plus
264 if the argument is negative; otherwise, it is
equal to the argument. This value is converted to a string of
ASCII digits in octal (base 8) with no extra leading
0s.
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'.
return toUnsignedString(i, 3);
|
| public static java.lang.String | toString(long i, int radix)Returns a string representation of the first argument in the
radix specified by the second argument.
If the radix is smaller than Character.MIN_RADIX
or larger than Character.MAX_RADIX, then the radix
10 is used instead.
If the first argument is negative, the first element of the
result is the ASCII minus sign '-'
('\u002d'). If the first argument is not
negative, no sign character appears in the result.
The remaining characters of the result represent the magnitude
of the first argument. If the magnitude is zero, it is
represented by a single zero character '0'
('\u0030'); otherwise, the first character of
the representation of the magnitude will not be the zero
character. The following ASCII characters are used as digits:
0123456789abcdefghijklmnopqrstuvwxyz
These are '\u0030' through
'\u0039' and '\u0061' through
'\u007a'. If radix is
N, then the first N of these characters
are used as radix-N digits in the order shown. Thus,
the digits for hexadecimal (radix 16) are
0123456789abcdef. If uppercase letters are
desired, the {@link java.lang.String#toUpperCase()} method may
be called on the result:
Long.toString(n, 16).toUpperCase()
if (radix < Character.MIN_RADIX || radix > Character.MAX_RADIX)
radix = 10;
if (radix == 10)
return toString(i);
char[] buf = new char[65];
int charPos = 64;
boolean negative = (i < 0);
if (!negative) {
i = -i;
}
while (i <= -radix) {
buf[charPos--] = Integer.digits[(int)(-(i % radix))];
i = i / radix;
}
buf[charPos] = Integer.digits[(int)(-i)];
if (negative) {
buf[--charPos] = '-";
}
return new String(buf, charPos, (65 - charPos));
|
| public java.lang.String | toString()Returns a String object representing this
Long's value. The value is converted to signed
decimal representation and returned as a string, exactly as if
the long value were given as an argument to the
{@link java.lang.Long#toString(long)} method.
return String.valueOf(value);
|
| public static java.lang.String | toString(long i)Returns a String object representing the specified
long. The argument is converted to signed decimal
representation and returned as a string, exactly as if the
argument and the radix 10 were given as arguments to the {@link
#toString(long, int)} method.
if (i == Long.MIN_VALUE)
return "-9223372036854775808";
int size = (i < 0) ? stringSize(-i) + 1 : stringSize(i);
char[] buf = new char[size];
getChars(i, size, buf);
return new String(0, size, buf);
|
| private static java.lang.String | toUnsignedString(long i, int shift)Convert the integer to an unsigned number.
char[] buf = new char[64];
int charPos = 64;
int radix = 1 << shift;
long mask = radix - 1;
do {
buf[--charPos] = Integer.digits[(int)(i & mask)];
i >>>= shift;
} while (i != 0);
return new String(buf, charPos, (64 - charPos));
|
| public static java.lang.Long | valueOf(java.lang.String s, int radix)Returns a Long object holding the value
extracted from the specified String when parsed
with the radix given by the second argument. The first
argument is interpreted as representing a signed
long in the radix specified by the second
argument, exactly as if the arguments were given to the {@link
#parseLong(java.lang.String, int)} method. The result is a
Long object that represents the long
value specified by the string.
In other words, this method returns a Long object equal
to the value of:
new Long(Long.parseLong(s, radix))
return new Long(parseLong(s, radix));
|
| public static java.lang.Long | valueOf(java.lang.String s)Returns a Long object holding the value
of the specified String. The argument is
interpreted as representing a signed decimal long,
exactly as if the argument were given to the {@link
#parseLong(java.lang.String)} method. The result is a
Long object that represents the integer value
specified by the string.
In other words, this method returns a Long object
equal to the value of:
new Long(Long.parseLong(s))
return new Long(parseLong(s, 10));
|
| public static java.lang.Long | valueOf(long l)Returns a Long instance representing the specified
long value.
If a new Long instance is not required, this method
should generally be used in preference to the constructor
{@link #Long(long)}, as this method is likely to yield
significantly better space and time performance by caching
frequently requested values.
for(int i = 0; i < cache.length; i++)
cache[i] = new Long(i - 128);
final int offset = 128;
if (l >= -128 && l <= 127) { // will cache
return LongCache.cache[(int)l + offset];
}
return new Long(l);
|
