/*
*
*
* Copyright 1990-2007 Sun Microsystems, Inc. All Rights Reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License version
* 2 only, as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License version 2 for more details (a copy is
* included at /legal/license.txt).
*
* You should have received a copy of the GNU General Public License
* version 2 along with this work; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA
*
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa
* Clara, CA 95054 or visit www.sun.com if you need additional
* information or have any questions.
*/
package java.lang;
/**
* The Long class wraps a value of the primitive type <code>long</code>
* in an object. An object of type <code>Long</code> contains a single
* field whose type is <code>long</code>.
* <p>
* In addition, this class provides several methods for converting a
* <code>long</code> to a <code>String</code> and a
* <code>String</code> to a <code>long</code>, as well as other
* constants and methods useful when dealing with a
* <code>long</code>.
*
* @version 1.51, 12/04/99 (CLDC 1.0, Spring 2000)
* @since JDK1.0
*/
public final class Long {
/**
* The smallest value of type <code>long</code>.
*/
public static final long MIN_VALUE = 0x8000000000000000L;
/**
* The largest value of type <code>long</code>.
*/
public static final long MAX_VALUE = 0x7fffffffffffffffL;
/**
* Creates a string representation of the first argument in the
* radix specified by the second argument.
* <p>
* If the radix is smaller than <code>Character.MIN_RADIX</code> or
* larger than <code>Character.MAX_RADIX</code>, then the radix
* <code>10</code> is used instead.
* <p>
* If the first argument is negative, the first element of the
* result is the ASCII minus sign <code>'-'</code>
* (<code>'\u002d'</code>. If the first argument is not negative,
* no sign character appears in the result.
* <p>
* 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'</code>
* (<code>'\u0030'</code>); otherwise, the first character of the
* representation of the magnitude will not be the zero character.
* The following ASCII characters are used as digits:
* <blockquote><pre>
* 0123456789abcdefghijklmnopqrstuvwxyz
* </pre></blockquote>
* These are <tt>'\u0030'</tt> through <tt>'\u0039'</tt>
* and <tt>'\u0061'</tt> through <tt>'\u007a'</tt>. If the
* radix is <var>N</var>, then the first <var>N</var> of these
* characters are used as radix-<var>N</var> digits in the order
* shown. Thus, the digits for hexadecimal (radix 16) are
* <blockquote><pre>
* <tt>0123456789abcdef</tt>.
* </pre></blockquote>
*
* @param i a long.
* @param radix the radix.
* @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;
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 new String object representing the specified integer.
* 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 that takes two arguments.
*
* @param i a <code>long</code> to be converted.
* @return a string representation of the argument in base 10.
*/
public static String toString(long i) {
return toString(i, 10);
}
/**
* Parses the string argument as a signed <code>long</code> 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 <code>Character.digit</code> returns a
* nonnegative value), except that the first character may be an
* ASCII minus sign <code>'-'</code> (<tt>'\u002d'</tt> to indicate
* a negative value. The resulting <code>long</code> value is returned.
* <p>
* Note that neither <tt>L</tt> nor <tt>l</tt> 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 <tt>L</tt>
* or <tt>l</tt> may appear as a digit for a radix greater than 22.
* <p>
* An exception of type <tt>NumberFormatException</tt> is thrown if any of
* the following situations occurs:
* <ul>
* <li>The first argument is <tt>null</tt> or is a string of length zero.
* <li>The <tt>radix</tt> is either smaller than
* {@link java.lang.Character#MIN_RADIX} or larger than
* {@link java.lang.Character#MAX_RADIX}.
* <li>The first character of the string is not a digit of the
* specified <tt>radix</tt> and is not a minus sign <tt>'-'</tt>
* (<tt>'\u002d'</tt>).
* <li>The first character of the string is a minus sign and the
* string is of length 1.
* <li>Any character of the string after the first is not a digit of
* the specified <tt>radix</tt>.
* <li>The integer value represented by the string cannot be
* represented as a value of type <tt>long</tt>.
* </ul><p>
* Examples:
* <blockquote><pre>
* 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
* </pre></blockquote>
*
* @param s the <code>String</code> containing the
* <code>long</code>.
* @param radix the radix to be used.
* @return the <code>long</code> represented by the string argument in
* the specified radix.
* @exception NumberFormatException if the string does not contain a
* parsable integer.
*/
public static long parseLong(String s, int radix)
throws NumberFormatException
{
if (s == null) {
throw new NumberFormatException(
/* #ifdef VERBOSE_EXCEPTIONS */
/// skipped "null"
/* #endif */
);
}
if (radix < Character.MIN_RADIX) {
throw new NumberFormatException(
/* #ifdef VERBOSE_EXCEPTIONS */
/// skipped "radix " + radix + " less than Character.MIN_RADIX"
/* #endif */
);
}
if (radix > Character.MAX_RADIX) {
throw new NumberFormatException(
/* #ifdef VERBOSE_EXCEPTIONS */
/// skipped "radix " + radix + " greater than Character.MAX_RADIX"
/* #endif */
);
}
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 new NumberFormatException(
/* #ifdef VERBOSE_EXCEPTIONS */
/// skipped s
/* #endif */
);
} else {
result = -digit;
}
}
while (i < max) {
// Accumulating negatively avoids surprises near MAX_VALUE
digit = Character.digit(s.charAt(i++),radix);
if (digit < 0) {
throw new NumberFormatException(
/* #ifdef VERBOSE_EXCEPTIONS */
/// skipped s
/* #endif */
);
}
if (result < multmin) {
throw new NumberFormatException(
/* #ifdef VERBOSE_EXCEPTIONS */
/// skipped s
/* #endif */
);
}
result *= radix;
if (result < limit + digit) {
throw new NumberFormatException(
/* #ifdef VERBOSE_EXCEPTIONS */
/// skipped s
/* #endif */
);
}
result -= digit;
}
} else {
throw new NumberFormatException(
/* #ifdef VERBOSE_EXCEPTIONS */
/// skipped s
/* #endif */
);
}
if (negative) {
if (i > 1) {
return result;
} else { /* Only got "-" */
throw new NumberFormatException(
/* #ifdef VERBOSE_EXCEPTIONS */
/// skipped s
/* #endif */
);
}
} else {
return -result;
}
}
/**
* Parses the string argument as a signed decimal <code>long</code>.
* The characters in the string must all be decimal digits, except
* that the first character may be an ASCII minus sign
* <code>'-'</code> (<code>\u002d'</code>) to indicate a negative
* value. The resulting long value is returned, exactly as if the
* argument and the radix <tt>10</tt> were given as arguments to the
* {@link #parseLong(String, int)} method that takes two arguments.
* <p>
* Note that neither <tt>L</tt> nor <tt>l</tt> 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 string.
* @return the <code>long</code> represented by the argument in decimal.
* @exception NumberFormatException if the string does not contain a
* parsable <code>long</code>.
*/
public static long parseLong(String s) throws NumberFormatException {
return parseLong(s, 10);
}
/**
* The value of the Long.
*
* @serial
*/
private long value;
/**
* Constructs a newly allocated <code>Long</code> object that
* represents the primitive <code>long</code> argument.
*
* @param value the value to be represented by the
* <code>Long</code> object.
*/
public Long(long value) {
this.value = value;
}
/**
* Returns the value of this Long as a long value.
*
* @return the <code>long</code> value represented by this object.
*/
public long longValue() {
return (long)value;
}
/**
* Returns a String object representing this Long's value.
* The long integer value represented by this Long object 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 #toString(long)} method that takes one argument.
*
* @return a string representation of this object in base 10.
*/
public String toString() {
return String.valueOf(value);
}
/**
* Computes a hashcode for this Long. The result is the exclusive
* OR of the two halves of the primitive <code>long</code> value
* represented by this <code>Long</code> object. That is, the hashcode
* is the value of the expression:
* <blockquote><pre>
* (int)(this.longValue()^(this.longValue()>>>32))
* </pre></blockquote>
*
* @return a hash code value for this object.
*/
public int hashCode() {
return (int)(value ^ (value >> 32));
}
/**
* Compares this object against the specified object.
* The result is <code>true</code> if and only if the argument is
* not <code>null</code> and is a <code>Long</code> object that
* contains the same <code>long</code> value as this object.
*
* @param obj the object to compare with.
* @return <code>true</code> if the objects are the same;
* <code>false</code> otherwise.
*/
public boolean equals(Object obj) {
if (obj instanceof Long) {
return value == ((Long)obj).longValue();
}
return false;
}
}
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