Package org.codehaus.groovy.runtime.typehandling

Class NumberMath

java.lang.Object

org.codehaus.groovy.runtime.typehandling.NumberMath

Direct Known Subclasses:

BigDecimalMath, BigIntegerMath, FloatingPointMath, IntegerMath, LongMath

public abstract class NumberMath
extends java.lang.Object

Stateless objects used to perform math on the various Number subclasses. Instances are required so that polymorphic calls work properly, but each subclass creates a singleton instance to minimize garbage. All methods must be thread-safe. The design goals of this class are as follows:

1. Support a 'least surprising' math model to scripting language users. This means that exact, or decimal math should be used for default calculations. This scheme assumes that by default, groovy literals with decimal points are instantiated as BigDecimal objects rather than binary floating points (Float, Double).
2. Do not force the appearance of exactness on a number that is by definition not guaranteed to be exact. In particular this means that if an operand in a NumberMath operation is a binary floating point number, ensure that the result remains a binary floating point number (i.e. never automatically promote a binary floating point number to a BigDecimal). This has the effect of preserving the expectations of binary floating point users and helps performance.
3. Provide an implementation that is as close as practical to the Java 1.5 BigDecimal math model which implements precision based floating point decimal math (ANSI X3.274-1996 and ANSI X3.274-1996/AM 1-2000 (section 7.4).

Constructor Summary

Constructors

Constructor	Description
NumberMath()

Method Summary

Modifier and Type	Method	Description
static java.lang.Number	abs(java.lang.Number number)
protected abstract java.lang.Number	absImpl(java.lang.Number number)
static java.lang.Number	add(java.lang.Number left, java.lang.Number right)
abstract java.lang.Number	addImpl(java.lang.Number left, java.lang.Number right)
static java.lang.Number	and(java.lang.Number left, java.lang.Number right)
protected java.lang.Number	andImpl(java.lang.Number left, java.lang.Number right)
static java.lang.Number	bitwiseNegate(java.lang.Number left)
protected java.lang.Number	bitwiseNegateImpl(java.lang.Number left)
static int	compareTo(java.lang.Number left, java.lang.Number right)
abstract int	compareToImpl(java.lang.Number left, java.lang.Number right)
protected java.lang.UnsupportedOperationException	createUnsupportedException(java.lang.String operation, java.lang.Number left)
static java.lang.Number	divide(java.lang.Number left, java.lang.Number right)
abstract java.lang.Number	divideImpl(java.lang.Number left, java.lang.Number right)
static NumberMath	getMath(java.lang.Number left, java.lang.Number right)	Determine which NumberMath instance to use, given the supplied operands.
static java.lang.Number	intdiv(java.lang.Number left, java.lang.Number right)
protected java.lang.Number	intdivImpl(java.lang.Number left, java.lang.Number right)
static boolean	isBigDecimal(java.lang.Number number)
static boolean	isBigInteger(java.lang.Number number)
static boolean	isByte(java.lang.Number number)
static boolean	isFloatingPoint(java.lang.Number number)
static boolean	isInteger(java.lang.Number number)
static boolean	isLong(java.lang.Number number)
static boolean	isShort(java.lang.Number number)
static java.lang.Number	leftShift(java.lang.Number left, java.lang.Number right)	For this operation, consider the operands independently.
protected java.lang.Number	leftShiftImpl(java.lang.Number left, java.lang.Number right)
static java.lang.Number	mod(java.lang.Number left, java.lang.Number right)
protected java.lang.Number	modImpl(java.lang.Number left, java.lang.Number right)
static java.lang.Number	multiply(java.lang.Number left, java.lang.Number right)
abstract java.lang.Number	multiplyImpl(java.lang.Number left, java.lang.Number right)
static java.lang.Number	or(java.lang.Number left, java.lang.Number right)
protected java.lang.Number	orImpl(java.lang.Number left, java.lang.Number right)
static java.lang.Number	rightShift(java.lang.Number left, java.lang.Number right)	For this operation, consider the operands independently.
protected java.lang.Number	rightShiftImpl(java.lang.Number left, java.lang.Number right)
static java.lang.Number	rightShiftUnsigned(java.lang.Number left, java.lang.Number right)	For this operation, consider the operands independently.
protected java.lang.Number	rightShiftUnsignedImpl(java.lang.Number left, java.lang.Number right)
static java.lang.Number	subtract(java.lang.Number left, java.lang.Number right)
abstract java.lang.Number	subtractImpl(java.lang.Number left, java.lang.Number right)
static java.math.BigDecimal	toBigDecimal(java.lang.Number n)
static java.math.BigInteger	toBigInteger(java.lang.Number n)
static java.lang.Number	unaryMinus(java.lang.Number left)
protected abstract java.lang.Number	unaryMinusImpl(java.lang.Number left)
static java.lang.Number	unaryPlus(java.lang.Number left)
protected abstract java.lang.Number	unaryPlusImpl(java.lang.Number left)
static java.lang.Number	xor(java.lang.Number left, java.lang.Number right)
protected java.lang.Number	xorImpl(java.lang.Number left, java.lang.Number right)

Methods inherited from class java.lang.Object

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

Constructor Detail

NumberMath

public NumberMath()

Method Detail

abs

public static java.lang.Number abs(java.lang.Number number)

add

public static java.lang.Number add(java.lang.Number left,
                                   java.lang.Number right)

subtract

public static java.lang.Number subtract(java.lang.Number left,
                                        java.lang.Number right)

multiply

public static java.lang.Number multiply(java.lang.Number left,
                                        java.lang.Number right)

divide

public static java.lang.Number divide(java.lang.Number left,
                                      java.lang.Number right)

compareTo

public static int compareTo(java.lang.Number left,
                            java.lang.Number right)

or

public static java.lang.Number or(java.lang.Number left,
                                  java.lang.Number right)

and

public static java.lang.Number and(java.lang.Number left,
                                   java.lang.Number right)

xor

public static java.lang.Number xor(java.lang.Number left,
                                   java.lang.Number right)

intdiv

public static java.lang.Number intdiv(java.lang.Number left,
                                      java.lang.Number right)

mod

public static java.lang.Number mod(java.lang.Number left,
                                   java.lang.Number right)

leftShift

public static java.lang.Number leftShift(java.lang.Number left,
                                         java.lang.Number right)

For this operation, consider the operands independently. Throw an exception if the right operand (shift distance) is not an integral type. For the left operand (shift value) also require an integral type, but do NOT promote from Integer to Long. This is consistent with Java, and makes sense for the shift operators.

rightShift

public static java.lang.Number rightShift(java.lang.Number left,
                                          java.lang.Number right)

For this operation, consider the operands independently. Throw an exception if the right operand (shift distance) is not an integral type. For the left operand (shift value) also require an integral type, but do NOT promote from Integer to Long. This is consistent with Java, and makes sense for the shift operators.

rightShiftUnsigned

public static java.lang.Number rightShiftUnsigned(java.lang.Number left,
                                                  java.lang.Number right)

For this operation, consider the operands independently. Throw an exception if the right operand (shift distance) is not an integral type. For the left operand (shift value) also require an integral type, but do NOT promote from Integer to Long. This is consistent with Java, and makes sense for the shift operators.

bitwiseNegate

public static java.lang.Number bitwiseNegate(java.lang.Number left)

unaryMinus

public static java.lang.Number unaryMinus(java.lang.Number left)

unaryPlus

public static java.lang.Number unaryPlus(java.lang.Number left)

isFloatingPoint

public static boolean isFloatingPoint(java.lang.Number number)

isInteger

public static boolean isInteger(java.lang.Number number)

isShort

public static boolean isShort(java.lang.Number number)

isByte

public static boolean isByte(java.lang.Number number)

isLong

public static boolean isLong(java.lang.Number number)

isBigDecimal

public static boolean isBigDecimal(java.lang.Number number)

isBigInteger

public static boolean isBigInteger(java.lang.Number number)

toBigDecimal

public static java.math.BigDecimal toBigDecimal(java.lang.Number n)

toBigInteger

public static java.math.BigInteger toBigInteger(java.lang.Number n)

getMath

public static NumberMath getMath(java.lang.Number left,
                                 java.lang.Number right)

Determine which NumberMath instance to use, given the supplied operands. This method implements the type promotion rules discussed in the documentation. Note that by the time this method is called, any Byte, Character or Short operands will have been promoted to Integer. For reference, here is the promotion matrix: bD bI D F L I bD bD bD D D bD bD bI bD bI D D bI bI D D D D D D D F D D D D D D L bD bI D D L L I bD bI D D L I Note that for division, if either operand isFloatingPoint, the result will be floating. Otherwise, the result is BigDecimal

absImpl

protected abstract java.lang.Number absImpl(java.lang.Number number)

addImpl

public abstract java.lang.Number addImpl(java.lang.Number left,
                                         java.lang.Number right)

subtractImpl

public abstract java.lang.Number subtractImpl(java.lang.Number left,
                                              java.lang.Number right)

multiplyImpl

public abstract java.lang.Number multiplyImpl(java.lang.Number left,
                                              java.lang.Number right)

divideImpl

public abstract java.lang.Number divideImpl(java.lang.Number left,
                                            java.lang.Number right)

compareToImpl

public abstract int compareToImpl(java.lang.Number left,
                                  java.lang.Number right)

unaryMinusImpl

protected abstract java.lang.Number unaryMinusImpl(java.lang.Number left)

unaryPlusImpl

protected abstract java.lang.Number unaryPlusImpl(java.lang.Number left)

bitwiseNegateImpl

protected java.lang.Number bitwiseNegateImpl(java.lang.Number left)

orImpl

protected java.lang.Number orImpl(java.lang.Number left,
                                  java.lang.Number right)

andImpl

protected java.lang.Number andImpl(java.lang.Number left,
                                   java.lang.Number right)

xorImpl

protected java.lang.Number xorImpl(java.lang.Number left,
                                   java.lang.Number right)

modImpl

protected java.lang.Number modImpl(java.lang.Number left,
                                   java.lang.Number right)

intdivImpl

protected java.lang.Number intdivImpl(java.lang.Number left,
                                      java.lang.Number right)

leftShiftImpl

protected java.lang.Number leftShiftImpl(java.lang.Number left,
                                         java.lang.Number right)

rightShiftImpl

protected java.lang.Number rightShiftImpl(java.lang.Number left,
                                          java.lang.Number right)

rightShiftUnsignedImpl

protected java.lang.Number rightShiftUnsignedImpl(java.lang.Number left,
                                                  java.lang.Number right)

createUnsupportedException

protected java.lang.UnsupportedOperationException createUnsupportedException(java.lang.String operation,
                                                                             java.lang.Number left)