java.math

Class BigDecimal

Implemented Interfaces:
Comparable, Serializable

public class BigDecimal
extends Number
implements Comparable

See Also:
Serialized Form

Field Summary

static BigDecimal
ONE
The constant one as a BigDecimal with scale zero.
static int
ROUND_CEILING
static int
ROUND_DOWN
static int
ROUND_FLOOR
static int
ROUND_HALF_DOWN
static int
ROUND_HALF_EVEN
static int
ROUND_HALF_UP
static int
ROUND_UNNECESSARY
static int
ROUND_UP
static BigDecimal
TEN
The constant ten as a BigDecimal with scale zero.
static BigDecimal
ZERO
The constant zero as a BigDecimal with scale zero.

Constructor Summary

BigDecimal(double num)
BigDecimal(String num)
BigDecimal(BigInteger num)
BigDecimal(BigInteger num, int scale)

Method Summary

BigDecimal
abs()
BigDecimal
add(BigDecimal val)
int
compareTo(Object val)
int
compareTo(BigDecimal val)
BigDecimal
divide(BigDecimal val, int roundingMode)
BigDecimal
divide(BigDecimal val, int newScale, int roundingMode)
double
doubleValue()
Return the value of this Number as a float.
boolean
equals(Object o)
Determine whether this Object is semantically equal to another Object.
float
floatValue()
Return the value of this Number as a float.
int
hashCode()
Get a value that represents this Object, as uniquely as possible within the confines of an int.
int
intValue()
Return the value of this Number as an int.
long
longValue()
Return the value of this Number as a long.
BigDecimal
max(BigDecimal val)
BigDecimal
min(BigDecimal val)
BigDecimal
movePointLeft(int n)
BigDecimal
movePointRight(int n)
BigDecimal
multiply(BigDecimal val)
BigDecimal
negate()
int
scale()
BigDecimal
setScale(int scale)
BigDecimal
setScale(int scale, int roundingMode)
int
signum()
BigDecimal
subtract(BigDecimal val)
BigInteger
toBigInteger()
String
toString()
Convert this Object to a human-readable String.
BigInteger
unscaledValue()
static BigDecimal
valueOf(long val)
static BigDecimal
valueOf(long val, int scale)

Methods inherited from class java.lang.Number

byteValue, doubleValue, floatValue, intValue, longValue, shortValue

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

ONE

public static final BigDecimal ONE
The constant one as a BigDecimal with scale zero.
Since:
1.5

ROUND_CEILING

public static final int ROUND_CEILING
Field Value:
2

ROUND_DOWN

public static final int ROUND_DOWN
Field Value:
1

ROUND_FLOOR

public static final int ROUND_FLOOR
Field Value:
3

ROUND_HALF_DOWN

public static final int ROUND_HALF_DOWN
Field Value:
5

ROUND_HALF_EVEN

public static final int ROUND_HALF_EVEN
Field Value:
6

ROUND_HALF_UP

public static final int ROUND_HALF_UP
Field Value:
4

ROUND_UNNECESSARY

public static final int ROUND_UNNECESSARY
Field Value:
7

ROUND_UP

public static final int ROUND_UP
Field Value:
0

TEN

public static final BigDecimal TEN
The constant ten as a BigDecimal with scale zero.
Since:
1.5

ZERO

public static final BigDecimal ZERO
The constant zero as a BigDecimal with scale zero.
Since:
1.5

Constructor Details

BigDecimal

public BigDecimal(double num)
            throws NumberFormatException

BigDecimal

public BigDecimal(String num)
            throws NumberFormatException

BigDecimal

public BigDecimal(BigInteger num)

BigDecimal

public BigDecimal(BigInteger num,
                  int scale)
            throws NumberFormatException

Method Details

abs

public BigDecimal abs()

add

public BigDecimal add(BigDecimal val)

compareTo

public int compareTo(Object val)
Specified by:
compareTo in interface Comparable

compareTo

public int compareTo(BigDecimal val)

divide

public BigDecimal divide(BigDecimal val,
                         int roundingMode)
            throws ArithmeticException,
                   IllegalArgumentException

divide

public BigDecimal divide(BigDecimal val,
                         int newScale,
                         int roundingMode)
            throws ArithmeticException,
                   IllegalArgumentException

doubleValue

public double doubleValue()
Return the value of this Number as a float.
Overrides:
doubleValue in interface Number
Returns:
the double value

equals

public boolean equals(Object o)
Determine whether this Object is semantically equal to another Object.

There are some fairly strict requirements on this method which subclasses must follow:

  • It must be transitive. If a.equals(b) and b.equals(c), then a.equals(c) must be true as well.
  • It must be symmetric. a.equals(b) and b.equals(a) must have the same value.
  • It must be reflexive. a.equals(a) must always be true.
  • It must be consistent. Whichever value a.equals(b) returns on the first invocation must be the value returned on all later invocations.
  • a.equals(null) must be false.
  • It must be consistent with hashCode(). That is, a.equals(b) must imply a.hashCode() == b.hashCode(). The reverse is not true; two objects that are not equal may have the same hashcode, but that has the potential to harm hashing performance.

This is typically overridden to throw a ClassCastException if the argument is not comparable to the class performing the comparison, but that is not a requirement. It is legal for a.equals(b) to be true even though a.getClass() != b.getClass(). Also, it is typical to never cause a NullPointerException.

In general, the Collections API (java.util) use the equals method rather than the == operator to compare objects. However, IdentityHashMap is an exception to this rule, for its own good reasons.

The default implementation returns this == o.

Overrides:
equals in interface Object
Parameters:
Returns:
whether this Object is semantically equal to another

floatValue

public float floatValue()
Return the value of this Number as a float.
Overrides:
floatValue in interface Number
Returns:
the float value

hashCode

public int hashCode()
Get a value that represents this Object, as uniquely as possible within the confines of an int.

There are some requirements on this method which subclasses must follow:

  • Semantic equality implies identical hashcodes. In other words, if a.equals(b) is true, then a.hashCode() == b.hashCode() must be as well. However, the reverse is not necessarily true, and two objects may have the same hashcode without being equal.
  • It must be consistent. Whichever value o.hashCode() returns on the first invocation must be the value returned on all later invocations as long as the object exists. Notice, however, that the result of hashCode may change between separate executions of a Virtual Machine, because it is not invoked on the same object.

Notice that since hashCode is used in Hashtable and other hashing classes, a poor implementation will degrade the performance of hashing (so don't blindly implement it as returning a constant!). Also, if calculating the hash is time-consuming, a class may consider caching the results.

The default implementation returns System.identityHashCode(this)

Overrides:
hashCode in interface Object
Returns:
the hash code for this Object

intValue

public int intValue()
Return the value of this Number as an int.
Overrides:
intValue in interface Number
Returns:
the int value

longValue

public long longValue()
Return the value of this Number as a long.
Overrides:
longValue in interface Number
Returns:
the long value

max

public BigDecimal max(BigDecimal val)

min

public BigDecimal min(BigDecimal val)

movePointLeft

public BigDecimal movePointLeft(int n)

movePointRight

public BigDecimal movePointRight(int n)

multiply

public BigDecimal multiply(BigDecimal val)

negate

public BigDecimal negate()

scale

public int scale()

setScale

public BigDecimal setScale(int scale)
            throws ArithmeticException

setScale

public BigDecimal setScale(int scale,
                           int roundingMode)
            throws ArithmeticException,
                   IllegalArgumentException

signum

public int signum()

subtract

public BigDecimal subtract(BigDecimal val)

toBigInteger

public BigInteger toBigInteger()

toString

public String toString()
Convert this Object to a human-readable String. There are no limits placed on how long this String should be or what it should contain. We suggest you make it as intuitive as possible to be able to place it into System.out.println() and such.

It is typical, but not required, to ensure that this method never completes abruptly with a RuntimeException.

This method will be called when performing string concatenation with this object. If the result is null, string concatenation will instead use "null".

The default implementation returns getClass().getName() + "@" + Integer.toHexString(hashCode()).

Overrides:
toString in interface Object
Returns:
the String representing this Object, which may be null

unscaledValue

public BigInteger unscaledValue()

valueOf

public static BigDecimal valueOf(long val)

valueOf

public static BigDecimal valueOf(long val,
                                 int scale)
            throws NumberFormatException

java.math.BigDecimal -- Arbitrary precision decimals. Copyright (C) 1999, 2000, 2001, 2003 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. Linking this library statically or dynamically with other modules is making a combined work based on this library. Thus, the terms and conditions of the GNU General Public License cover the whole combination. As a special exception, the copyright holders of this library give you permission to link this library with independent modules to produce an executable, regardless of the license terms of these independent modules, and to copy and distribute the resulting executable under terms of your choice, provided that you also meet, for each linked independent module, the terms and conditions of the license of that module. An independent module is a module which is not derived from or based on this library. If you modify this library, you may extend this exception to your version of the library, but you are not obligated to do so. If you do not wish to do so, delete this exception statement from your version.