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MathContext

public final class MathContext
extends Object implements Serializable

java.lang.Object
   ↳ java.math.MathContext


Immutable objects describing settings such as rounding mode and digit precision for the numerical operations provided by class BigDecimal.

Summary

Fields

public static final MathContext DECIMAL128

A MathContext which corresponds to the IEEE 754 quadruple decimal precision format: 34 digit precision and RoundingMode.HALF_EVEN rounding.

public static final MathContext DECIMAL32

A MathContext which corresponds to the IEEE 754 single decimal precision format: 7 digit precision and RoundingMode.HALF_EVEN rounding.

public static final MathContext DECIMAL64

A MathContext which corresponds to the IEEE 754 double decimal precision format: 16 digit precision and RoundingMode.HALF_EVEN rounding.

public static final MathContext UNLIMITED

A MathContext for unlimited precision with RoundingMode.HALF_UP rounding.

Public constructors

MathContext(int precision)

Constructs a new MathContext with the specified precision and with the rounding mode HALF_UP.

MathContext(int precision, RoundingMode roundingMode)

Constructs a new MathContext with the specified precision and with the specified rounding mode.

MathContext(String s)

Constructs a new MathContext from a string.

Public methods

boolean equals(Object x)

Returns true if x is a MathContext with the same precision setting and the same rounding mode as this MathContext instance.

int getPrecision()

Returns the precision.

RoundingMode getRoundingMode()

Returns the rounding mode.

int hashCode()

Returns the hash code for this MathContext instance.

String toString()

Returns the string representation for this MathContext instance.

Inherited methods

Fields

DECIMAL128

added in API level 1
public static final MathContext DECIMAL128

A MathContext which corresponds to the IEEE 754 quadruple decimal precision format: 34 digit precision and RoundingMode.HALF_EVEN rounding.

DECIMAL32

added in API level 1
public static final MathContext DECIMAL32

A MathContext which corresponds to the IEEE 754 single decimal precision format: 7 digit precision and RoundingMode.HALF_EVEN rounding.

DECIMAL64

added in API level 1
public static final MathContext DECIMAL64

A MathContext which corresponds to the IEEE 754 double decimal precision format: 16 digit precision and RoundingMode.HALF_EVEN rounding.

UNLIMITED

added in API level 1
public static final MathContext UNLIMITED

A MathContext for unlimited precision with RoundingMode.HALF_UP rounding.

Public constructors

MathContext

added in API level 1
public MathContext (int precision)

Constructs a new MathContext with the specified precision and with the rounding mode HALF_UP. If the precision passed is zero, then this implies that the computations have to be performed exact, the rounding mode in this case is irrelevant.

Parameters
precision int: the precision for the new MathContext.

Throws
IllegalArgumentException if precision < 0.

MathContext

added in API level 1
public MathContext (int precision, 
                RoundingMode roundingMode)

Constructs a new MathContext with the specified precision and with the specified rounding mode. If the precision passed is zero, then this implies that the computations have to be performed exact, the rounding mode in this case is irrelevant.

Parameters
precision int: the precision for the new MathContext.

roundingMode RoundingMode: the rounding mode for the new MathContext.

Throws
IllegalArgumentException if precision < 0.
NullPointerException if roundingMode is null.

MathContext

added in API level 1
public MathContext (String s)

Constructs a new MathContext from a string. The string has to specify the precision and the rounding mode to be used and has to follow the following syntax: "precision=<precision> roundingMode=<roundingMode>" This is the same form as the one returned by the toString() method.

Parameters
s String

Throws
IllegalArgumentException if the string is not in the correct format or if the precision specified is < 0.

Public methods

equals

added in API level 1
public boolean equals (Object x)

Returns true if x is a MathContext with the same precision setting and the same rounding mode as this MathContext instance.

Parameters
x Object: object to be compared.

Returns
boolean true if this MathContext instance is equal to the x argument; false otherwise.

getPrecision

added in API level 1
public int getPrecision ()

Returns the precision. The precision is the number of digits used for an operation. Results are rounded to this precision. The precision is guaranteed to be non negative. If the precision is zero, then the computations have to be performed exact, results are not rounded in this case.

Returns
int the precision.

getRoundingMode

added in API level 1
public RoundingMode getRoundingMode ()

Returns the rounding mode. The rounding mode is the strategy to be used to round results.

The rounding mode is one of RoundingMode.UP, RoundingMode.DOWN, RoundingMode.CEILING, RoundingMode.FLOOR, RoundingMode.HALF_UP, RoundingMode.HALF_DOWN, RoundingMode.HALF_EVEN, or RoundingMode.UNNECESSARY.

Returns
RoundingMode the rounding mode.

hashCode

added in API level 1
public int hashCode ()

Returns the hash code for this MathContext instance.

Returns
int the hash code for this MathContext.

toString

added in API level 1
public String toString ()

Returns the string representation for this MathContext instance. The string has the form "precision=<precision> roundingMode=<roundingMode>" where <precision> is an integer describing the number of digits used for operations and <roundingMode> is the string representation of the rounding mode.

Returns
String a string representation for this MathContext instance