In addition, this class provides several methods for converting - * a {@code long} to a {@code String} and a {@code String} to a {@code - * long}, as well as other constants and methods useful when dealing - * with a {@code long}. - * - *
Implementation note: The implementations of the "bit twiddling"
- * methods (such as {@link #highestOneBit(long) highestOneBit} and
- * {@link #numberOfTrailingZeros(long) numberOfTrailingZeros}) are
- * based on material from Henry S. Warren, Jr.'s Hacker's
- * Delight, (Addison Wesley, 2002).
- *
- * @author Lee Boynton
- * @author Arthur van Hoff
- * @author Josh Bloch
- * @author Joseph D. Darcy
- * @since JDK1.0
- */
-public final class Long extends Number implements Comparable If the radix is smaller than {@code Character.MIN_RADIX}
- * or larger than {@code Character.MAX_RADIX}, then the radix
- * {@code 10} is used instead.
- *
- * If the first argument is negative, the first element of the
- * result is the ASCII minus sign {@code '-'}
- * ( 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 {@code '0'}
- * ( The unsigned {@code 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 {@code 0}s. If the unsigned magnitude is zero, it
- * is represented by a single zero character {@code '0'}
- * ( The unsigned {@code 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
- * {@code 0}s.
- *
- * If the unsigned magnitude is zero, it is represented by a
- * single zero character {@code '0'}
- * ( The unsigned {@code 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
- * {@code 0}s. If the unsigned magnitude is zero, it is
- * represented by a single zero character {@code '0'}
- * ( Note that neither the character {@code L}
- * ( An exception of type {@code NumberFormatException} is
- * thrown if any of the following situations occurs:
- * Examples:
- * Note that neither the character {@code L}
- * ( In other words, this method returns a {@code Long} object equal
- * to the value of:
- *
- * In other words, this method returns a {@code Long} object
- * equal to the value of:
- *
- *
- * The sequence of characters following an optional
- * sign and/or radix specifier ("{@code 0x}", "{@code 0X}",
- * "{@code #}", or leading zero) is parsed as by the {@code
- * 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 {@code String} is
- * the minus sign. No whitespace characters are permitted in the
- * {@code String}.
- *
- * @param nm the {@code String} to decode.
- * @return a {@code Long} object holding the {@code long}
- * value represented by {@code nm}
- * @throws NumberFormatException if the {@code String} does not
- * contain a parsable {@code long}.
- * @see java.lang.Long#parseLong(String, int)
- * @since 1.2
- */
- public static Long decode(String nm) throws NumberFormatException {
- int radix = 10;
- int index = 0;
- boolean negative = false;
- Long result;
-
- if (nm.length() == 0)
- throw new NumberFormatException("Zero length string");
- char firstChar = nm.charAt(0);
- // Handle sign, if present
- if (firstChar == '-') {
- negative = true;
- index++;
- } else if (firstChar == '+')
- 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) || nm.startsWith("+", index))
- throw new NumberFormatException("Sign character in wrong position");
-
- try {
- result = Long.valueOf(nm.substring(index), radix);
- result = negative ? Long.valueOf(-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 ? ("-" + nm.substring(index))
- : nm.substring(index);
- result = Long.valueOf(constant, radix);
- }
- return result;
- }
-
- /**
- * The value of the {@code Long}.
- *
- * @serial
- */
- private final long value;
-
- /**
- * Constructs a newly allocated {@code Long} object that
- * represents the specified {@code long} argument.
- *
- * @param value the value to be represented by the
- * {@code Long} object.
- */
- public Long(long value) {
- this.value = value;
- }
-
- /**
- * Constructs a newly allocated {@code Long} object that
- * represents the {@code long} value indicated by the
- * {@code String} parameter. The string is converted to a
- * {@code long} value in exactly the manner used by the
- * {@code parseLong} method for radix 10.
- *
- * @param s the {@code String} to be converted to a
- * {@code Long}.
- * @throws NumberFormatException if the {@code String} does not
- * contain a parsable {@code long}.
- * @see java.lang.Long#parseLong(java.lang.String, int)
- */
- public Long(String s) throws NumberFormatException {
- this.value = parseLong(s, 10);
- }
-
- /**
- * Returns the value of this {@code Long} as a
- * {@code byte}.
- */
- public byte byteValue() {
- return (byte)value;
- }
-
- /**
- * Returns the value of this {@code Long} as a
- * {@code short}.
- */
- public short shortValue() {
- return (short)value;
- }
-
- /**
- * Returns the value of this {@code Long} as an
- * {@code int}.
- */
- public int intValue() {
- return (int)value;
- }
-
- /**
- * Returns the value of this {@code Long} as a
- * {@code long} value.
- */
- public long longValue() {
- return (long)value;
- }
-
- /**
- * Returns the value of this {@code Long} as a
- * {@code float}.
- */
- public float floatValue() {
- return (float)value;
- }
-
- /**
- * Returns the value of this {@code Long} as a
- * {@code double}.
- */
- public double doubleValue() {
- return (double)value;
- }
-
- /**
- * Returns a {@code String} object representing this
- * {@code Long}'s value. The value is converted to signed
- * decimal representation and returned as a string, exactly as if
- * the {@code long} value were given as an argument to the
- * {@link java.lang.Long#toString(long)} method.
- *
- * @return a string representation of the value of this object in
- * base 10.
- */
- public String toString() {
- return toString(value);
- }
-
- /**
- * Returns a hash code for this {@code Long}. The result is
- * the exclusive OR of the two halves of the primitive
- * {@code long} value held by this {@code Long}
- * object. That is, the hashcode is the value of the expression:
- *
- * 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
- * {@code long} value and a {@code Long} object
- * representing this value is returned. Details of possible
- * numeric formats can be found with the definition of
- * {@code getProperty}.
- *
- * If there is no property with the specified name, if the
- * specified name is empty or {@code null}, or if the
- * property does not have the correct numeric format, then
- * {@code null} is returned.
- *
- * In other words, this method returns a {@code Long} object equal to
- * the value of:
- *
- * 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
- * {@code long} value and a {@code Long} object
- * representing this value is returned. Details of possible
- * numeric formats can be found with the definition of
- * {@code getProperty}.
- *
- * The second argument is the default value. A {@code 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 {@code Long} object equal
- * to the value of:
- *
- * Note that, in every case, neither {@code L}
- * ( 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 {@code null}.
- *
- * @param nm property name.
- * @param val default value.
- * @return the {@code Long} value of the property.
- * @see java.lang.System#getProperty(java.lang.String)
- * @see java.lang.System#getProperty(java.lang.String, java.lang.String)
- * @see java.lang.Long#decode
- */
- public static Long getLong(String nm, Long val) {
- String v = null;
- try {
- v = AbstractStringBuilder.getProperty(nm);
- } catch (IllegalArgumentException e) {
- } catch (NullPointerException e) {
- }
- if (v != null) {
- try {
- return Long.decode(v);
- } catch (NumberFormatException e) {
- }
- }
- return val;
- }
-
- /**
- * Compares two {@code Long} objects numerically.
- *
- * @param anotherLong the {@code Long} to be compared.
- * @return the value {@code 0} if this {@code Long} is
- * equal to the argument {@code Long}; a value less than
- * {@code 0} if this {@code Long} is numerically less
- * than the argument {@code Long}; and a value greater
- * than {@code 0} if this {@code Long} is numerically
- * greater than the argument {@code Long} (signed
- * comparison).
- * @since 1.2
- */
- public int compareTo(Long anotherLong) {
- return compare(this.value, anotherLong.value);
- }
-
- /**
- * Compares two {@code long} values numerically.
- * The value returned is identical to what would be returned by:
- * Note that this method is closely related to the logarithm base 2.
- * For all positive {@code long} values x:
- * Note that left rotation with a negative distance is equivalent to
- * right rotation: {@code 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: {@code rotateLeft(val,
- * distance) == rotateLeft(val, distance & 0x3F)}.
- *
- * @return the value obtained by rotating the two's complement binary
- * representation of the specified {@code long} value left by the
- * specified number of bits.
- * @since 1.5
- */
- public static long rotateLeft(long i, int distance) {
- return (i << distance) | (i >>> -distance);
- }
-
- /**
- * Returns the value obtained by rotating the two's complement binary
- * representation of the specified {@code 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: {@code 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: {@code rotateRight(val,
- * distance) == rotateRight(val, distance & 0x3F)}.
- *
- * @return the value obtained by rotating the two's complement binary
- * representation of the specified {@code long} value right by the
- * specified number of bits.
- * @since 1.5
- */
- public static long rotateRight(long i, int distance) {
- return (i >>> distance) | (i << -distance);
- }
-
- /**
- * Returns the value obtained by reversing the order of the bits in the
- * two's complement binary representation of the specified {@code long}
- * value.
- *
- * @return the value obtained by reversing order of the bits in the
- * specified {@code long} value.
- * @since 1.5
- */
- public static long reverse(long i) {
- // 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;
- }
-
- /**
- * Returns the signum function of the specified {@code 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.)
- *
- * @return the signum function of the specified {@code long} value.
- * @since 1.5
- */
- public static int signum(long i) {
- // HD, Section 2-7
- return (int) ((i >> 63) | (-i >>> 63));
- }
-
- /**
- * Returns the value obtained by reversing the order of the bytes in the
- * two's complement representation of the specified {@code long} value.
- *
- * @return the value obtained by reversing the bytes in the specified
- * {@code long} value.
- * @since 1.5
- */
- public static long reverseBytes(long i) {
- i = (i & 0x00ff00ff00ff00ffL) << 8 | (i >>> 8) & 0x00ff00ff00ff00ffL;
- return (i << 48) | ((i & 0xffff0000L) << 16) |
- ((i >>> 16) & 0xffff0000L) | (i >>> 48);
- }
-
- /** use serialVersionUID from JDK 1.0.2 for interoperability */
- private static final long serialVersionUID = 4290774380558885855L;
-}
'\u002d'). If the first argument is not
- * negative, no sign character appears in the result.
- *
- * '\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:
- *
- *
- * {@code 0123456789abcdefghijklmnopqrstuvwxyz}
- *
- *
- * These are '\u0030' through
- * '\u0039' and '\u0061' through
- * '\u007a'. If {@code 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
- * {@code 0123456789abcdef}. If uppercase letters are
- * desired, the {@link java.lang.String#toUpperCase()} method may
- * be called on the result:
- *
- *
- * {@code Long.toString(n, 16).toUpperCase()}
- *
- *
- * @param i a {@code long} to be converted to a string.
- * @param radix the radix to use in the string representation.
- * @return a string representation of the argument in the specified radix.
- * @see java.lang.Character#MAX_RADIX
- * @see java.lang.Character#MIN_RADIX
- */
- public static String toString(long i, int radix) {
- 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));
- }
-
- /**
- * Returns a string representation of the {@code long}
- * argument as an unsigned integer in base 16.
- *
- * '\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:
- *
- *
- * {@code 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:
- *
- *
- * {@code Long.toHexString(n).toUpperCase()}
- *
- *
- * @param i a {@code long} to be converted to a string.
- * @return the string representation of the unsigned {@code long}
- * value represented by the argument in hexadecimal
- * (base 16).
- * @since JDK 1.0.2
- */
- public static String toHexString(long i) {
- return toUnsignedString(i, 4);
- }
-
- /**
- * Returns a string representation of the {@code long}
- * argument as an unsigned integer in base 8.
- *
- * '\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:
- *
- *
- * {@code 01234567}
- *
- *
- * These are the characters '\u0030' through
- * '\u0037'.
- *
- * @param i a {@code long} to be converted to a string.
- * @return the string representation of the unsigned {@code long}
- * value represented by the argument in octal (base 8).
- * @since JDK 1.0.2
- */
- public static String toOctalString(long i) {
- return toUnsignedString(i, 3);
- }
-
- /**
- * Returns a string representation of the {@code long}
- * argument as an unsigned integer in base 2.
- *
- * '\u0030'); otherwise, the first character of
- * the representation of the unsigned magnitude will not be the
- * zero character. The characters {@code '0'}
- * ('\u0030') and {@code '1'}
- * ('\u0031') are used as binary digits.
- *
- * @param i a {@code long} to be converted to a string.
- * @return the string representation of the unsigned {@code long}
- * value represented by the argument in binary (base 2).
- * @since JDK 1.0.2
- */
- public static String toBinaryString(long i) {
- return toUnsignedString(i, 1);
- }
-
- /**
- * Convert the integer to an unsigned number.
- */
- private static String toUnsignedString(long i, int shift) {
- 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));
- }
-
- /**
- * Returns a {@code String} object representing the specified
- * {@code 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.
- *
- * @param i a {@code long} to be converted.
- * @return a string representation of the argument in base 10.
- */
- @JavaScriptBody(args = "i", body = "return i.toExactString();")
- public static String toString(long i) {
- 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(buf, 0, size);
- }
-
- /**
- * 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
- */
- static void getChars(long i, int index, char[] buf) {
- 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;
- }
- }
-
- // Requires positive x
- 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;
- }
-
- /**
- * Parses the string argument as a signed {@code 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 {@code '-'} ('\u002D') to
- * indicate a negative value or an ASCII plus sign {@code '+'}
- * ('\u002B') to indicate a positive value. The
- * resulting {@code long} value is returned.
- *
- * '\u004C') nor {@code 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
- * {@code L} or {@code l} may appear as a digit for a
- * radix greater than 22.
- *
- *
- *
- *
- *
- * '\u002d') or plus sign {@code
- * '+'} ('\u002B') provided that the string is
- * longer than length 1.
- *
- *
- *
- * @param s the {@code String} containing the
- * {@code long} representation to be parsed.
- * @param radix the radix to be used while parsing {@code s}.
- * @return the {@code long} represented by the string argument in
- * the specified radix.
- * @throws NumberFormatException if the string does not contain a
- * parsable {@code long}.
- */
- public static long parseLong(String s, int radix)
- throws NumberFormatException
- {
- 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, len = s.length();
- long limit = -Long.MAX_VALUE;
- long multmin;
- int digit;
-
- if (len > 0) {
- char firstChar = s.charAt(0);
- if (firstChar < '0') { // Possible leading "+" or "-"
- if (firstChar == '-') {
- negative = true;
- limit = Long.MIN_VALUE;
- } else if (firstChar != '+')
- throw NumberFormatException.forInputString(s);
-
- if (len == 1) // Cannot have lone "+" or "-"
- throw NumberFormatException.forInputString(s);
- i++;
- }
- multmin = limit / radix;
- while (i < len) {
- // 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);
- }
- return negative ? result : -result;
- }
-
- /**
- * Parses the string argument as a signed decimal {@code long}.
- * The characters in the string must all be decimal digits, except
- * that the first character may be an ASCII minus sign {@code '-'}
- * (
- * 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
- * \u002D') to indicate a negative value or an
- * ASCII plus sign {@code '+'} ('\u002B') to
- * indicate a positive value. The resulting {@code long} value is
- * returned, exactly as if the argument and the radix {@code 10}
- * were given as arguments to the {@link
- * #parseLong(java.lang.String, int)} method.
- *
- * '\u004C') nor {@code 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.
- *
- * @param s a {@code String} containing the {@code long}
- * representation to be parsed
- * @return the {@code long} represented by the argument in
- * decimal.
- * @throws NumberFormatException if the string does not contain a
- * parsable {@code long}.
- */
- public static long parseLong(String s) throws NumberFormatException {
- return parseLong(s, 10);
- }
-
- /**
- * Returns a {@code Long} object holding the value
- * extracted from the specified {@code String} when parsed
- * with the radix given by the second argument. The first
- * argument is interpreted as representing a signed
- * {@code 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
- * {@code Long} object that represents the {@code long}
- * value specified by the string.
- *
- *
- * {@code new Long(Long.parseLong(s, radix))}
- *
- *
- * @param s the string to be parsed
- * @param radix the radix to be used in interpreting {@code s}
- * @return a {@code Long} object holding the value
- * represented by the string argument in the specified
- * radix.
- * @throws NumberFormatException If the {@code String} does not
- * contain a parsable {@code long}.
- */
- public static Long valueOf(String s, int radix) throws NumberFormatException {
- return Long.valueOf(parseLong(s, radix));
- }
-
- /**
- * Returns a {@code Long} object holding the value
- * of the specified {@code String}. The argument is
- * interpreted as representing a signed decimal {@code long},
- * exactly as if the argument were given to the {@link
- * #parseLong(java.lang.String)} method. The result is a
- * {@code Long} object that represents the integer value
- * specified by the string.
- *
- *
- * {@code new Long(Long.parseLong(s))}
- *
- *
- * @param s the string to be parsed.
- * @return a {@code Long} object holding the value
- * represented by the string argument.
- * @throws NumberFormatException If the string cannot be parsed
- * as a {@code long}.
- */
- public static Long valueOf(String s) throws NumberFormatException
- {
- return Long.valueOf(parseLong(s, 10));
- }
-
- private static class LongCache {
- private LongCache(){}
-
- static final Long cache[] = new Long[-(-128) + 127 + 1];
-
- static {
- for(int i = 0; i < cache.length; i++)
- cache[i] = new Long(i - 128);
- }
- }
-
- /**
- * Returns a {@code Long} instance representing the specified
- * {@code long} value.
- * If a new {@code 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.
- *
- * Note that unlike the {@linkplain Integer#valueOf(int)
- * corresponding method} in the {@code Integer} class, this method
- * is not required to cache values within a particular
- * range.
- *
- * @param l a long value.
- * @return a {@code Long} instance representing {@code l}.
- * @since 1.5
- */
- public static Long valueOf(long l) {
- final int offset = 128;
- if (l >= -128 && l <= 127) { // will cache
- return LongCache.cache[(int)l + offset];
- }
- return new Long(l);
- }
-
- /**
- * Decodes a {@code String} into a {@code Long}.
- * Accepts decimal, hexadecimal, and octal numbers given by the
- * following grammar:
- *
- *
- *
- *
- * DecimalNumeral, HexDigits, and OctalDigits
- * are as defined in section 3.10.1 of
- * The Java™ Language Specification,
- * except that underscores are not accepted between digits.
- *
- *
- *
- *
- * {@code (int)(this.longValue()^(this.longValue()>>>32))}
- *
- *
- * @return a hash code value for this object.
- */
- public int hashCode() {
- return (int)(value ^ (value >>> 32));
- }
-
- /**
- * Compares this object to the specified object. The result is
- * {@code true} if and only if the argument is not
- * {@code null} and is a {@code Long} object that
- * contains the same {@code long} value as this object.
- *
- * @param obj the object to compare with.
- * @return {@code true} if the objects are the same;
- * {@code false} otherwise.
- */
- public boolean equals(Object obj) {
- if (obj instanceof Long) {
- return value == ((Long)obj).longValue();
- }
- return false;
- }
-
- /**
- * Determines the {@code long} value of the system property
- * with the specified name.
- *
- *
- * {@code getLong(nm, null)}
- *
- *
- * @param nm property name.
- * @return the {@code Long} value of the property.
- * @see java.lang.System#getProperty(java.lang.String)
- * @see java.lang.System#getProperty(java.lang.String, java.lang.String)
- */
- public static Long getLong(String nm) {
- return getLong(nm, null);
- }
-
- /**
- * Determines the {@code long} value of the system property
- * with the specified name.
- *
- *
- * {@code getLong(nm, new Long(val))}
- *
- *
- * but in practice it may be implemented in a manner such as:
- *
- *
- *
- * to avoid the unnecessary allocation of a {@code Long} object when
- * the default value is not needed.
- *
- * @param nm property name.
- * @param val default value.
- * @return the {@code Long} value of the property.
- * @see java.lang.System#getProperty(java.lang.String)
- * @see java.lang.System#getProperty(java.lang.String, java.lang.String)
- */
- public static Long getLong(String nm, long val) {
- Long result = Long.getLong(nm, null);
- return (result == null) ? Long.valueOf(val) : result;
- }
-
- /**
- * Returns the {@code 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 {@code long} value, as per the
- * {@code Long.decode} method, and a {@code Long} object
- * representing this value is returned.
- *
- *
- * Long result = getLong(nm, null);
- * return (result == null) ? new Long(val) : result;
- *
- *
- *
- * '\u004C') nor {@code 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.
- *
- *
- * Long.valueOf(x).compareTo(Long.valueOf(y))
- *
- *
- * @param x the first {@code long} to compare
- * @param y the second {@code long} to compare
- * @return the value {@code 0} if {@code x == y};
- * a value less than {@code 0} if {@code x < y}; and
- * a value greater than {@code 0} if {@code x > y}
- * @since 1.7
- */
- public static int compare(long x, long y) {
- return (x < y) ? -1 : ((x == y) ? 0 : 1);
- }
-
-
- // Bit Twiddling
-
- /**
- * The number of bits used to represent a {@code long} value in two's
- * complement binary form.
- *
- * @since 1.5
- */
- public static final int SIZE = 64;
-
- /**
- * Returns a {@code long} value with at most a single one-bit, in the
- * position of the highest-order ("leftmost") one-bit in the specified
- * {@code 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.
- *
- * @return a {@code long} value with a single one-bit, in the position
- * of the highest-order one-bit in the specified value, or zero if
- * the specified value is itself equal to zero.
- * @since 1.5
- */
- public static long highestOneBit(long i) {
- // 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);
- }
-
- /**
- * Returns a {@code long} value with at most a single one-bit, in the
- * position of the lowest-order ("rightmost") one-bit in the specified
- * {@code 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.
- *
- * @return a {@code long} value with a single one-bit, in the position
- * of the lowest-order one-bit in the specified value, or zero if
- * the specified value is itself equal to zero.
- * @since 1.5
- */
- public static long lowestOneBit(long i) {
- // HD, Section 2-1
- return i & -i;
- }
-
- /**
- * Returns the number of zero bits preceding the highest-order
- * ("leftmost") one-bit in the two's complement binary representation
- * of the specified {@code 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.
- *
- *
- *
- *
- * @return the number of zero bits preceding the highest-order
- * ("leftmost") one-bit in the two's complement binary representation
- * of the specified {@code long} value, or 64 if the value
- * is equal to zero.
- * @since 1.5
- */
- public static int numberOfLeadingZeros(long i) {
- // 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;
- }
-
- /**
- * Returns the number of zero bits following the lowest-order ("rightmost")
- * one-bit in the two's complement binary representation of the specified
- * {@code 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.
- *
- * @return the number of zero bits following the lowest-order ("rightmost")
- * one-bit in the two's complement binary representation of the
- * specified {@code long} value, or 64 if the value is equal
- * to zero.
- * @since 1.5
- */
- public static int numberOfTrailingZeros(long i) {
- // 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);
- }
-
- /**
- * Returns the number of one-bits in the two's complement binary
- * representation of the specified {@code long} value. This function is
- * sometimes referred to as the population count.
- *
- * @return the number of one-bits in the two's complement binary
- * representation of the specified {@code long} value.
- * @since 1.5
- */
- public static int bitCount(long i) {
- // 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;
- }
-
- /**
- * Returns the value obtained by rotating the two's complement binary
- * representation of the specified {@code 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.)
- *
- *