mirror of
git://gcc.gnu.org/git/gcc.git
synced 2024-12-25 15:49:42 +08:00
373 lines
9.9 KiB
Java
373 lines
9.9 KiB
Java
/* java.math.BigDecimal -- Arbitrary precision decimals.
|
||
Copyright (C) 1999, 2000, 2001 Free Software Foundation, Inc.
|
||
|
||
This file is part of GNU Classpath.
|
||
|
||
GNU Classpath is free software; you can redistribute it and/or modify
|
||
it under the terms of the GNU General Public License as published by
|
||
the Free Software Foundation; either version 2, or (at your option)
|
||
any later version.
|
||
|
||
GNU Classpath 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 for more details.
|
||
|
||
You should have received a copy of the GNU General Public License
|
||
along with GNU Classpath; see the file COPYING. If not, write to the
|
||
Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
|
||
02111-1307 USA.
|
||
|
||
As a special exception, if you link this library with other files to
|
||
produce an executable, this library does not by itself cause the
|
||
resulting executable to be covered by the GNU General Public License.
|
||
This exception does not however invalidate any other reasons why the
|
||
executable file might be covered by the GNU General Public License. */
|
||
|
||
package java.math;
|
||
|
||
import java.math.BigInteger;
|
||
|
||
public class BigDecimal extends Number implements Comparable {
|
||
private BigInteger intVal;
|
||
private int scale;
|
||
private static final long serialVersionUID = 6108874887143696463L;
|
||
|
||
private final static BigDecimal ZERO =
|
||
new BigDecimal (BigInteger.valueOf (0), 0);
|
||
|
||
private final static BigDecimal ONE =
|
||
new BigDecimal (BigInteger.valueOf (1), 0);
|
||
|
||
public final static int ROUND_UP = 0;
|
||
public final static int ROUND_DOWN = 1;
|
||
public final static int ROUND_CEILING = 2;
|
||
public final static int ROUND_FLOOR = 3;
|
||
public final static int ROUND_HALF_UP = 4;
|
||
public final static int ROUND_HALF_DOWN = 5;
|
||
public final static int ROUND_HALF_EVEN = 6;
|
||
public final static int ROUND_UNNECESSARY = 7;
|
||
|
||
public BigDecimal (BigInteger num)
|
||
{
|
||
this (num, 0);
|
||
}
|
||
|
||
public BigDecimal (BigInteger num, int scale) throws NumberFormatException
|
||
{
|
||
if (scale < 0)
|
||
throw new NumberFormatException ("scale of " + scale + " is < 0");
|
||
this.intVal = num;
|
||
this.scale = scale;
|
||
}
|
||
|
||
public BigDecimal (double num) throws NumberFormatException
|
||
{
|
||
this (Double.toString (num));
|
||
}
|
||
|
||
public BigDecimal (String num) throws NumberFormatException
|
||
{
|
||
int point = num.indexOf('.');
|
||
this.intVal = new BigInteger (point == -1 ? num :
|
||
num.substring (0, point) +
|
||
num.substring (point + 1));
|
||
scale = num.length() - (point == -1 ? num.length () : point + 1);
|
||
}
|
||
|
||
public static BigDecimal valueOf (long val)
|
||
{
|
||
return valueOf (val, 0);
|
||
}
|
||
|
||
public static BigDecimal valueOf (long val, int scale)
|
||
throws NumberFormatException
|
||
{
|
||
if (scale == 0)
|
||
switch ((int) val)
|
||
{
|
||
case 0:
|
||
return ZERO;
|
||
case 1:
|
||
return ONE;
|
||
}
|
||
|
||
return new BigDecimal (BigInteger.valueOf (val), scale);
|
||
}
|
||
|
||
public BigDecimal add (BigDecimal val)
|
||
{
|
||
// For addition, need to line up decimals. Note that the movePointRight
|
||
// method cannot be used for this as it might return a BigDecimal with
|
||
// scale == 0 instead of the scale we need.
|
||
BigInteger op1 = intVal;
|
||
BigInteger op2 = val.intVal;
|
||
if (scale < val.scale)
|
||
op1 = op1.multiply (BigInteger.valueOf (10).pow (val.scale - scale));
|
||
else if (scale > val.scale)
|
||
op2 = op2.multiply (BigInteger.valueOf (10).pow (scale - val.scale));
|
||
|
||
return new BigDecimal (op1.add (op2), Math.max (scale, val.scale));
|
||
}
|
||
|
||
public BigDecimal subtract (BigDecimal val)
|
||
{
|
||
return this.add(val.negate());
|
||
}
|
||
|
||
public BigDecimal multiply (BigDecimal val)
|
||
{
|
||
return new BigDecimal (intVal.multiply (val.intVal), scale + val.scale);
|
||
}
|
||
|
||
public BigDecimal divide (BigDecimal val, int roundingMode)
|
||
throws ArithmeticException, IllegalArgumentException
|
||
{
|
||
return divide (val, scale, roundingMode);
|
||
}
|
||
|
||
public BigDecimal divide(BigDecimal val, int newScale, int roundingMode)
|
||
throws ArithmeticException, IllegalArgumentException
|
||
{
|
||
if (roundingMode < 0 || roundingMode > 7)
|
||
throw
|
||
new IllegalArgumentException("illegal rounding mode: " + roundingMode);
|
||
|
||
if (newScale < 0)
|
||
throw new ArithmeticException ("scale is negative: " + newScale);
|
||
|
||
if (intVal.signum () == 0) // handle special case of 0.0/0.0
|
||
return ZERO;
|
||
|
||
// Ensure that pow gets a non-negative value.
|
||
int valScale = val.scale;
|
||
BigInteger valIntVal = val.intVal;
|
||
int power = newScale + 1 - (scale - val.scale);
|
||
if (power < 0)
|
||
{
|
||
// Effectively increase the scale of val to avoid an
|
||
// ArithmeticException for a negative power.
|
||
valIntVal = valIntVal.multiply (BigInteger.valueOf (10).pow (-power));
|
||
power = 0;
|
||
}
|
||
|
||
BigInteger dividend = intVal.multiply (BigInteger.valueOf (10).pow (power));
|
||
|
||
BigInteger parts[] = dividend.divideAndRemainder (valIntVal);
|
||
// System.out.println("int: " + parts[0]);
|
||
// System.out.println("rem: " + parts[1]);
|
||
|
||
int roundDigit = parts[0].mod (BigInteger.valueOf (10)).intValue ();
|
||
BigInteger unrounded = parts[0].divide (BigInteger.valueOf (10));
|
||
|
||
if (roundDigit == 0 && parts[1].signum () == 0) // no rounding necessary
|
||
return new BigDecimal (unrounded, newScale);
|
||
|
||
int sign = unrounded.signum ();
|
||
|
||
switch (roundingMode)
|
||
{
|
||
case ROUND_UNNECESSARY:
|
||
throw new ArithmeticException ("newScale is not large enough");
|
||
case ROUND_CEILING:
|
||
roundingMode = (sign == 1) ? ROUND_UP : ROUND_DOWN;
|
||
break;
|
||
case ROUND_FLOOR:
|
||
roundingMode = (sign == 1) ? ROUND_DOWN : ROUND_UP;
|
||
break;
|
||
case ROUND_HALF_UP:
|
||
roundingMode = (roundDigit >= 5) ? ROUND_UP : ROUND_DOWN;
|
||
break;
|
||
case ROUND_HALF_DOWN:
|
||
roundingMode = (roundDigit > 5) ? ROUND_UP : ROUND_DOWN;
|
||
break;
|
||
case ROUND_HALF_EVEN:
|
||
if (roundDigit < 5)
|
||
roundingMode = ROUND_DOWN;
|
||
else
|
||
{
|
||
int rightmost =
|
||
unrounded.mod (BigInteger.valueOf (10)).intValue ();
|
||
if (rightmost % 2 == 1) // odd, then ROUND_HALF_UP
|
||
roundingMode = ROUND_UP;
|
||
else // even, then ROUND_HALF_DOWN
|
||
roundingMode = (roundDigit > 5) ? ROUND_UP : ROUND_DOWN;
|
||
}
|
||
break;
|
||
}
|
||
|
||
if (roundingMode == ROUND_UP)
|
||
return new BigDecimal (unrounded.add (BigInteger.valueOf (1)), newScale);
|
||
|
||
// roundingMode == ROUND_DOWN
|
||
return new BigDecimal (unrounded, newScale);
|
||
}
|
||
|
||
public int compareTo (BigDecimal val)
|
||
{
|
||
if (scale == val.scale)
|
||
return intVal.compareTo (val.intVal);
|
||
|
||
BigInteger thisParts[] =
|
||
intVal.divideAndRemainder (BigInteger.valueOf (10).pow (scale));
|
||
BigInteger valParts[] =
|
||
val.intVal.divideAndRemainder (BigInteger.valueOf (10).pow (val.scale));
|
||
|
||
int compare;
|
||
if ((compare = thisParts[0].compareTo (valParts[0])) != 0)
|
||
return compare;
|
||
|
||
// quotients are the same, so compare remainders
|
||
|
||
// remove trailing zeros
|
||
if (thisParts[1].equals (BigInteger.valueOf (0)) == false)
|
||
while (thisParts[1].mod (BigInteger.valueOf (10)).equals
|
||
(BigInteger.valueOf (0)))
|
||
thisParts[1] = thisParts[1].divide (BigInteger.valueOf (10));
|
||
// again...
|
||
if (valParts[1].equals(BigInteger.valueOf (0)) == false)
|
||
while (valParts[1].mod (BigInteger.valueOf (10)).equals
|
||
(BigInteger.valueOf (0)))
|
||
valParts[1] = valParts[1].divide (BigInteger.valueOf (10));
|
||
|
||
// and compare them
|
||
return thisParts[1].compareTo (valParts[1]);
|
||
}
|
||
|
||
public int compareTo (Object val)
|
||
{
|
||
return(compareTo((BigDecimal)val));
|
||
}
|
||
|
||
public boolean equals (Object o)
|
||
{
|
||
return (o instanceof BigDecimal
|
||
&& scale == ((BigDecimal) o).scale
|
||
&& compareTo ((BigDecimal) o) == 0);
|
||
}
|
||
|
||
public int hashCode()
|
||
{
|
||
return intValue() ^ scale;
|
||
}
|
||
|
||
public BigDecimal max (BigDecimal val)
|
||
{
|
||
switch (compareTo (val))
|
||
{
|
||
case 1:
|
||
return this;
|
||
default:
|
||
return val;
|
||
}
|
||
}
|
||
|
||
public BigDecimal min (BigDecimal val)
|
||
{
|
||
switch (compareTo (val))
|
||
{
|
||
case -1:
|
||
return this;
|
||
default:
|
||
return val;
|
||
}
|
||
}
|
||
|
||
public BigDecimal movePointLeft (int n)
|
||
{
|
||
return (n < 0) ? movePointRight (-n) : new BigDecimal (intVal, scale + n);
|
||
}
|
||
|
||
public BigDecimal movePointRight (int n)
|
||
{
|
||
if (n < 0)
|
||
return movePointLeft (-n);
|
||
|
||
if (scale >= n)
|
||
return new BigDecimal (intVal, scale - n);
|
||
|
||
return new BigDecimal (intVal.multiply
|
||
(BigInteger.valueOf (10).pow (n - scale)), 0);
|
||
}
|
||
|
||
public int signum ()
|
||
{
|
||
return intVal.signum ();
|
||
}
|
||
|
||
public int scale ()
|
||
{
|
||
return scale;
|
||
}
|
||
|
||
public BigDecimal abs ()
|
||
{
|
||
return new BigDecimal (intVal.abs (), scale);
|
||
}
|
||
|
||
public BigDecimal negate ()
|
||
{
|
||
return new BigDecimal (intVal.negate (), scale);
|
||
}
|
||
|
||
public String toString ()
|
||
{
|
||
String bigStr = intVal.toString();
|
||
if (scale == 0)
|
||
return bigStr;
|
||
|
||
int point = bigStr.length() - scale;
|
||
boolean negative = (bigStr.charAt(0) == '-');
|
||
StringBuffer sb = new StringBuffer(bigStr.length() + 1 +
|
||
(point <= 0 ? -point+1 : 0));
|
||
if (negative)
|
||
sb.append('-');
|
||
while (point <= 0)
|
||
{
|
||
sb.append('0');
|
||
point++;
|
||
}
|
||
sb.append(bigStr.substring(negative ? 1 : 0));
|
||
sb.insert(point, '.');
|
||
return sb.toString();
|
||
}
|
||
|
||
public BigInteger toBigInteger ()
|
||
{
|
||
return scale == 0 ? intVal :
|
||
intVal.divide (BigInteger.valueOf (10).pow (scale));
|
||
}
|
||
|
||
|
||
public int intValue ()
|
||
{
|
||
return toBigInteger ().intValue ();
|
||
}
|
||
|
||
public long longValue ()
|
||
{
|
||
return toBigInteger().longValue();
|
||
}
|
||
|
||
public float floatValue()
|
||
{
|
||
return Float.valueOf(toString()).floatValue();
|
||
}
|
||
|
||
public double doubleValue()
|
||
{
|
||
return Double.valueOf(toString()).doubleValue();
|
||
}
|
||
|
||
public BigDecimal setScale (int scale) throws ArithmeticException
|
||
{
|
||
return setScale (scale, ROUND_UNNECESSARY);
|
||
}
|
||
|
||
public BigDecimal setScale (int scale, int roundingMode)
|
||
throws ArithmeticException, IllegalArgumentException
|
||
{
|
||
return divide (ONE, scale, roundingMode);
|
||
}
|
||
}
|